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
|
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* This implementation of poly1305 is by Andrew Moon
* (https://github.com/floodyberry/poly1305-donna) and released as public
* domain. */
#include <string.h>
#include "poly1305.h"
#if defined(_MSC_VER) && _MSC_VER < 1600
#include "prtypes.h"
typedef PRUint32 uint32_t;
typedef PRUint64 uint64_t;
#else
#include <stdint.h>
#endif
#if defined(NSS_X86) || defined(NSS_X64)
/* We can assume little-endian. */
static uint32_t
U8TO32_LE(const unsigned char *m)
{
uint32_t r;
memcpy(&r, m, sizeof(r));
return r;
}
static void
U32TO8_LE(unsigned char *m, uint32_t v)
{
memcpy(m, &v, sizeof(v));
}
#else
static uint32_t
U8TO32_LE(const unsigned char *m)
{
return (uint32_t)m[0] |
(uint32_t)m[1] << 8 |
(uint32_t)m[2] << 16 |
(uint32_t)m[3] << 24;
}
static void
U32TO8_LE(unsigned char *m, uint32_t v)
{
m[0] = v;
m[1] = v >> 8;
m[2] = v >> 16;
m[3] = v >> 24;
}
#endif
static uint64_t
mul32x32_64(uint32_t a, uint32_t b)
{
return (uint64_t)a * b;
}
struct poly1305_state_st {
uint32_t r0, r1, r2, r3, r4;
uint32_t s1, s2, s3, s4;
uint32_t h0, h1, h2, h3, h4;
unsigned char buf[16];
unsigned int buf_used;
unsigned char key[16];
};
/* update updates |state| given some amount of input data. This function may
* only be called with a |len| that is not a multiple of 16 at the end of the
* data. Otherwise the input must be buffered into 16 byte blocks. */
static void
update(struct poly1305_state_st *state, const unsigned char *in,
size_t len)
{
uint32_t t0, t1, t2, t3;
uint64_t t[5];
uint32_t b;
uint64_t c;
size_t j;
unsigned char mp[16];
if (len < 16)
goto poly1305_donna_atmost15bytes;
poly1305_donna_16bytes:
t0 = U8TO32_LE(in);
t1 = U8TO32_LE(in + 4);
t2 = U8TO32_LE(in + 8);
t3 = U8TO32_LE(in + 12);
in += 16;
len -= 16;
state->h0 += t0 & 0x3ffffff;
state->h1 += ((((uint64_t)t1 << 32) | t0) >> 26) & 0x3ffffff;
state->h2 += ((((uint64_t)t2 << 32) | t1) >> 20) & 0x3ffffff;
state->h3 += ((((uint64_t)t3 << 32) | t2) >> 14) & 0x3ffffff;
state->h4 += (t3 >> 8) | (1 << 24);
poly1305_donna_mul:
t[0] = mul32x32_64(state->h0, state->r0) +
mul32x32_64(state->h1, state->s4) +
mul32x32_64(state->h2, state->s3) +
mul32x32_64(state->h3, state->s2) +
mul32x32_64(state->h4, state->s1);
t[1] = mul32x32_64(state->h0, state->r1) +
mul32x32_64(state->h1, state->r0) +
mul32x32_64(state->h2, state->s4) +
mul32x32_64(state->h3, state->s3) +
mul32x32_64(state->h4, state->s2);
t[2] = mul32x32_64(state->h0, state->r2) +
mul32x32_64(state->h1, state->r1) +
mul32x32_64(state->h2, state->r0) +
mul32x32_64(state->h3, state->s4) +
mul32x32_64(state->h4, state->s3);
t[3] = mul32x32_64(state->h0, state->r3) +
mul32x32_64(state->h1, state->r2) +
mul32x32_64(state->h2, state->r1) +
mul32x32_64(state->h3, state->r0) +
mul32x32_64(state->h4, state->s4);
t[4] = mul32x32_64(state->h0, state->r4) +
mul32x32_64(state->h1, state->r3) +
mul32x32_64(state->h2, state->r2) +
mul32x32_64(state->h3, state->r1) +
mul32x32_64(state->h4, state->r0);
state->h0 = (uint32_t)t[0] & 0x3ffffff;
c = (t[0] >> 26);
t[1] += c;
state->h1 = (uint32_t)t[1] & 0x3ffffff;
b = (uint32_t)(t[1] >> 26);
t[2] += b;
state->h2 = (uint32_t)t[2] & 0x3ffffff;
b = (uint32_t)(t[2] >> 26);
t[3] += b;
state->h3 = (uint32_t)t[3] & 0x3ffffff;
b = (uint32_t)(t[3] >> 26);
t[4] += b;
state->h4 = (uint32_t)t[4] & 0x3ffffff;
b = (uint32_t)(t[4] >> 26);
state->h0 += b * 5;
if (len >= 16)
goto poly1305_donna_16bytes;
/* final bytes */
poly1305_donna_atmost15bytes:
if (!len)
return;
for (j = 0; j < len; j++)
mp[j] = in[j];
mp[j++] = 1;
for (; j < 16; j++)
mp[j] = 0;
len = 0;
t0 = U8TO32_LE(mp + 0);
t1 = U8TO32_LE(mp + 4);
t2 = U8TO32_LE(mp + 8);
t3 = U8TO32_LE(mp + 12);
state->h0 += t0 & 0x3ffffff;
state->h1 += ((((uint64_t)t1 << 32) | t0) >> 26) & 0x3ffffff;
state->h2 += ((((uint64_t)t2 << 32) | t1) >> 20) & 0x3ffffff;
state->h3 += ((((uint64_t)t3 << 32) | t2) >> 14) & 0x3ffffff;
state->h4 += (t3 >> 8);
goto poly1305_donna_mul;
}
void
Poly1305Init(poly1305_state *statep, const unsigned char key[32])
{
struct poly1305_state_st *state = (struct poly1305_state_st *)statep;
uint32_t t0, t1, t2, t3;
t0 = U8TO32_LE(key + 0);
t1 = U8TO32_LE(key + 4);
t2 = U8TO32_LE(key + 8);
t3 = U8TO32_LE(key + 12);
/* precompute multipliers */
state->r0 = t0 & 0x3ffffff;
t0 >>= 26;
t0 |= t1 << 6;
state->r1 = t0 & 0x3ffff03;
t1 >>= 20;
t1 |= t2 << 12;
state->r2 = t1 & 0x3ffc0ff;
t2 >>= 14;
t2 |= t3 << 18;
state->r3 = t2 & 0x3f03fff;
t3 >>= 8;
state->r4 = t3 & 0x00fffff;
state->s1 = state->r1 * 5;
state->s2 = state->r2 * 5;
state->s3 = state->r3 * 5;
state->s4 = state->r4 * 5;
/* init state */
state->h0 = 0;
state->h1 = 0;
state->h2 = 0;
state->h3 = 0;
state->h4 = 0;
state->buf_used = 0;
memcpy(state->key, key + 16, sizeof(state->key));
}
void
Poly1305Update(poly1305_state *statep, const unsigned char *in,
size_t in_len)
{
unsigned int i;
struct poly1305_state_st *state = (struct poly1305_state_st *)statep;
if (state->buf_used) {
unsigned int todo = 16 - state->buf_used;
if (todo > in_len)
todo = in_len;
for (i = 0; i < todo; i++)
state->buf[state->buf_used + i] = in[i];
state->buf_used += todo;
in_len -= todo;
in += todo;
if (state->buf_used == 16) {
update(state, state->buf, 16);
state->buf_used = 0;
}
}
if (in_len >= 16) {
size_t todo = in_len & ~0xf;
update(state, in, todo);
in += todo;
in_len &= 0xf;
}
if (in_len) {
for (i = 0; i < in_len; i++)
state->buf[i] = in[i];
state->buf_used = in_len;
}
}
void
Poly1305Finish(poly1305_state *statep, unsigned char mac[16])
{
struct poly1305_state_st *state = (struct poly1305_state_st *)statep;
uint64_t f0, f1, f2, f3;
uint32_t g0, g1, g2, g3, g4;
uint32_t b, nb;
if (state->buf_used)
update(state, state->buf, state->buf_used);
b = state->h0 >> 26;
state->h0 = state->h0 & 0x3ffffff;
state->h1 += b;
b = state->h1 >> 26;
state->h1 = state->h1 & 0x3ffffff;
state->h2 += b;
b = state->h2 >> 26;
state->h2 = state->h2 & 0x3ffffff;
state->h3 += b;
b = state->h3 >> 26;
state->h3 = state->h3 & 0x3ffffff;
state->h4 += b;
b = state->h4 >> 26;
state->h4 = state->h4 & 0x3ffffff;
state->h0 += b * 5;
g0 = state->h0 + 5;
b = g0 >> 26;
g0 &= 0x3ffffff;
g1 = state->h1 + b;
b = g1 >> 26;
g1 &= 0x3ffffff;
g2 = state->h2 + b;
b = g2 >> 26;
g2 &= 0x3ffffff;
g3 = state->h3 + b;
b = g3 >> 26;
g3 &= 0x3ffffff;
g4 = state->h4 + b - (1 << 26);
b = (g4 >> 31) - 1;
nb = ~b;
state->h0 = (state->h0 & nb) | (g0 & b);
state->h1 = (state->h1 & nb) | (g1 & b);
state->h2 = (state->h2 & nb) | (g2 & b);
state->h3 = (state->h3 & nb) | (g3 & b);
state->h4 = (state->h4 & nb) | (g4 & b);
f0 = ((state->h0) | (state->h1 << 26)) + (uint64_t)U8TO32_LE(&state->key[0]);
f1 = ((state->h1 >> 6) | (state->h2 << 20)) + (uint64_t)U8TO32_LE(&state->key[4]);
f2 = ((state->h2 >> 12) | (state->h3 << 14)) + (uint64_t)U8TO32_LE(&state->key[8]);
f3 = ((state->h3 >> 18) | (state->h4 << 8)) + (uint64_t)U8TO32_LE(&state->key[12]);
U32TO8_LE(&mac[0], (uint32_t)f0);
f1 += (f0 >> 32);
U32TO8_LE(&mac[4], (uint32_t)f1);
f2 += (f1 >> 32);
U32TO8_LE(&mac[8], (uint32_t)f2);
f3 += (f2 >> 32);
U32TO8_LE(&mac[12], (uint32_t)f3);
}
|
