1 /* Copyright (c) 2014, Google Inc.
2 *
3 * Permission to use, copy, modify, and/or distribute this software for any
4 * purpose with or without fee is hereby granted, provided that the above
5 * copyright notice and this permission notice appear in all copies.
6 *
7 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
8 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
10 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
12 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
13 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
14
15 /* This implementation was taken from the public domain, neon2 version in
16 * SUPERCOP by D. J. Bernstein and Peter Schwabe. */
17
18 #include <openssl/poly1305.h>
19
20 #if defined(OPENSSL_ARM) && !defined(OPENSSL_NO_ASM)
21
22 #include <string.h>
23
24
25 typedef struct {
26 uint32_t v[12]; /* for alignment; only using 10 */
27 } fe1305x2;
28
29 #define addmulmod openssl_poly1305_neon2_addmulmod
30 #define blocks openssl_poly1305_neon2_blocks
31
32 extern void addmulmod(fe1305x2 *r, const fe1305x2 *x, const fe1305x2 *y,
33 const fe1305x2 *c);
34
35 extern int blocks(fe1305x2 *h, const fe1305x2 *precomp, const uint8_t *in,
36 unsigned int inlen);
37
freeze(fe1305x2 * r)38 static void freeze(fe1305x2 *r) {
39 int i;
40
41 uint32_t x0 = r->v[0];
42 uint32_t x1 = r->v[2];
43 uint32_t x2 = r->v[4];
44 uint32_t x3 = r->v[6];
45 uint32_t x4 = r->v[8];
46 uint32_t y0;
47 uint32_t y1;
48 uint32_t y2;
49 uint32_t y3;
50 uint32_t y4;
51 uint32_t swap;
52
53 for (i = 0; i < 3; ++i) {
54 x1 += x0 >> 26;
55 x0 &= 0x3ffffff;
56 x2 += x1 >> 26;
57 x1 &= 0x3ffffff;
58 x3 += x2 >> 26;
59 x2 &= 0x3ffffff;
60 x4 += x3 >> 26;
61 x3 &= 0x3ffffff;
62 x0 += 5 * (x4 >> 26);
63 x4 &= 0x3ffffff;
64 }
65
66 y0 = x0 + 5;
67 y1 = x1 + (y0 >> 26);
68 y0 &= 0x3ffffff;
69 y2 = x2 + (y1 >> 26);
70 y1 &= 0x3ffffff;
71 y3 = x3 + (y2 >> 26);
72 y2 &= 0x3ffffff;
73 y4 = x4 + (y3 >> 26);
74 y3 &= 0x3ffffff;
75 swap = -(y4 >> 26);
76 y4 &= 0x3ffffff;
77
78 y0 ^= x0;
79 y1 ^= x1;
80 y2 ^= x2;
81 y3 ^= x3;
82 y4 ^= x4;
83
84 y0 &= swap;
85 y1 &= swap;
86 y2 &= swap;
87 y3 &= swap;
88 y4 &= swap;
89
90 y0 ^= x0;
91 y1 ^= x1;
92 y2 ^= x2;
93 y3 ^= x3;
94 y4 ^= x4;
95
96 r->v[0] = y0;
97 r->v[2] = y1;
98 r->v[4] = y2;
99 r->v[6] = y3;
100 r->v[8] = y4;
101 }
102
fe1305x2_tobytearray(uint8_t * r,fe1305x2 * x)103 static void fe1305x2_tobytearray(uint8_t *r, fe1305x2 *x) {
104 uint32_t x0 = x->v[0];
105 uint32_t x1 = x->v[2];
106 uint32_t x2 = x->v[4];
107 uint32_t x3 = x->v[6];
108 uint32_t x4 = x->v[8];
109
110 x1 += x0 >> 26;
111 x0 &= 0x3ffffff;
112 x2 += x1 >> 26;
113 x1 &= 0x3ffffff;
114 x3 += x2 >> 26;
115 x2 &= 0x3ffffff;
116 x4 += x3 >> 26;
117 x3 &= 0x3ffffff;
118
119 *(uint32_t *)r = x0 + (x1 << 26);
120 *(uint32_t *)(r + 4) = (x1 >> 6) + (x2 << 20);
121 *(uint32_t *)(r + 8) = (x2 >> 12) + (x3 << 14);
122 *(uint32_t *)(r + 12) = (x3 >> 18) + (x4 << 8);
123 }
124
125 /* load32 exists to avoid breaking strict aliasing rules in
126 * fe1305x2_frombytearray. */
load32(uint8_t * t)127 static uint32_t load32(uint8_t *t) {
128 uint32_t tmp;
129 memcpy(&tmp, t, sizeof(tmp));
130 return tmp;
131 }
132
fe1305x2_frombytearray(fe1305x2 * r,const uint8_t * x,unsigned long long xlen)133 static void fe1305x2_frombytearray(fe1305x2 *r, const uint8_t *x,
134 unsigned long long xlen) {
135 unsigned i;
136 uint8_t t[17];
137
138 for (i = 0; (i < 16) && (i < xlen); i++) {
139 t[i] = x[i];
140 }
141 xlen -= i;
142 x += i;
143 t[i++] = 1;
144 for (; i < 17; i++) {
145 t[i] = 0;
146 }
147
148 r->v[0] = 0x3ffffff & load32(t);
149 r->v[2] = 0x3ffffff & (load32(t + 3) >> 2);
150 r->v[4] = 0x3ffffff & (load32(t + 6) >> 4);
151 r->v[6] = 0x3ffffff & (load32(t + 9) >> 6);
152 r->v[8] = load32(t + 13);
153
154 if (xlen) {
155 for (i = 0; (i < 16) && (i < xlen); i++) {
156 t[i] = x[i];
157 }
158 t[i++] = 1;
159 for (; i < 17; i++) {
160 t[i] = 0;
161 }
162
163 r->v[1] = 0x3ffffff & load32(t);
164 r->v[3] = 0x3ffffff & (load32(t + 3) >> 2);
165 r->v[5] = 0x3ffffff & (load32(t + 6) >> 4);
166 r->v[7] = 0x3ffffff & (load32(t + 9) >> 6);
167 r->v[9] = load32(t + 13);
168 } else {
169 r->v[1] = r->v[3] = r->v[5] = r->v[7] = r->v[9] = 0;
170 }
171 }
172
173 static const fe1305x2 zero __attribute__((aligned(16)));
174
175 struct poly1305_state_st {
176 uint8_t data[sizeof(fe1305x2[5]) + 128];
177 uint8_t buf[32];
178 unsigned int buf_used;
179 uint8_t key[16];
180 };
181
CRYPTO_poly1305_init_neon(poly1305_state * state,const uint8_t key[32])182 void CRYPTO_poly1305_init_neon(poly1305_state *state, const uint8_t key[32]) {
183 struct poly1305_state_st *st = (struct poly1305_state_st *)(state);
184 fe1305x2 *const r = (fe1305x2 *)(st->data + (15 & (-(int)st->data)));
185 fe1305x2 *const h = r + 1;
186 fe1305x2 *const c = h + 1;
187 fe1305x2 *const precomp = c + 1;
188 unsigned int j;
189
190 r->v[1] = r->v[0] = 0x3ffffff & *(uint32_t *)key;
191 r->v[3] = r->v[2] = 0x3ffff03 & ((*(uint32_t *)(key + 3)) >> 2);
192 r->v[5] = r->v[4] = 0x3ffc0ff & ((*(uint32_t *)(key + 6)) >> 4);
193 r->v[7] = r->v[6] = 0x3f03fff & ((*(uint32_t *)(key + 9)) >> 6);
194 r->v[9] = r->v[8] = 0x00fffff & ((*(uint32_t *)(key + 12)) >> 8);
195
196 for (j = 0; j < 10; j++) {
197 h->v[j] = 0; /* XXX: should fast-forward a bit */
198 }
199
200 addmulmod(precomp, r, r, &zero); /* precompute r^2 */
201 addmulmod(precomp + 1, precomp, precomp, &zero); /* precompute r^4 */
202
203 memcpy(st->key, key + 16, 16);
204 st->buf_used = 0;
205 }
206
CRYPTO_poly1305_update_neon(poly1305_state * state,const uint8_t * in,size_t in_len)207 void CRYPTO_poly1305_update_neon(poly1305_state *state, const uint8_t *in,
208 size_t in_len) {
209 struct poly1305_state_st *st = (struct poly1305_state_st *)(state);
210 fe1305x2 *const r = (fe1305x2 *)(st->data + (15 & (-(int)st->data)));
211 fe1305x2 *const h = r + 1;
212 fe1305x2 *const c = h + 1;
213 fe1305x2 *const precomp = c + 1;
214 unsigned int i;
215
216 if (st->buf_used) {
217 unsigned int todo = 32 - st->buf_used;
218 if (todo > in_len) {
219 todo = in_len;
220 }
221 for (i = 0; i < todo; i++) {
222 st->buf[st->buf_used + i] = in[i];
223 }
224 st->buf_used += todo;
225 in_len -= todo;
226 in += todo;
227
228 if (st->buf_used == sizeof(st->buf) && in_len) {
229 addmulmod(h, h, precomp, &zero);
230 fe1305x2_frombytearray(c, st->buf, sizeof(st->buf));
231 for (i = 0; i < 10; i++) {
232 h->v[i] += c->v[i];
233 }
234 st->buf_used = 0;
235 }
236 }
237
238 while (in_len > 32) {
239 unsigned int tlen = 1048576;
240 if (in_len < tlen) {
241 tlen = in_len;
242 }
243 tlen -= blocks(h, precomp, in, tlen);
244 in_len -= tlen;
245 in += tlen;
246 }
247
248 if (in_len) {
249 for (i = 0; i < in_len; i++) {
250 st->buf[i] = in[i];
251 }
252 st->buf_used = in_len;
253 }
254 }
255
CRYPTO_poly1305_finish_neon(poly1305_state * state,uint8_t mac[16])256 void CRYPTO_poly1305_finish_neon(poly1305_state *state, uint8_t mac[16]) {
257 struct poly1305_state_st *st = (struct poly1305_state_st *)(state);
258 fe1305x2 *const r = (fe1305x2 *)(st->data + (15 & (-(int)st->data)));
259 fe1305x2 *const h = r + 1;
260 fe1305x2 *const c = h + 1;
261 fe1305x2 *const precomp = c + 1;
262
263 addmulmod(h, h, precomp, &zero);
264
265 if (st->buf_used > 16) {
266 fe1305x2_frombytearray(c, st->buf, st->buf_used);
267 precomp->v[1] = r->v[1];
268 precomp->v[3] = r->v[3];
269 precomp->v[5] = r->v[5];
270 precomp->v[7] = r->v[7];
271 precomp->v[9] = r->v[9];
272 addmulmod(h, h, precomp, c);
273 } else if (st->buf_used > 0) {
274 fe1305x2_frombytearray(c, st->buf, st->buf_used);
275 r->v[1] = 1;
276 r->v[3] = 0;
277 r->v[5] = 0;
278 r->v[7] = 0;
279 r->v[9] = 0;
280 addmulmod(h, h, r, c);
281 }
282
283 h->v[0] += h->v[1];
284 h->v[2] += h->v[3];
285 h->v[4] += h->v[5];
286 h->v[6] += h->v[7];
287 h->v[8] += h->v[9];
288 freeze(h);
289
290 fe1305x2_frombytearray(c, st->key, 16);
291 c->v[8] ^= (1 << 24);
292
293 h->v[0] += c->v[0];
294 h->v[2] += c->v[2];
295 h->v[4] += c->v[4];
296 h->v[6] += c->v[6];
297 h->v[8] += c->v[8];
298 fe1305x2_tobytearray(mac, h);
299 }
300
301 #endif /* OPENSSL_ARM && !OPENSSL_NO_ASM */
302