aboutsummaryrefslogtreecommitdiff
path: root/crypto/aegis128-neon-inner.c
blob: b6a52a386b220836d6268ade86672726a812d766 (plain)
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
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2019 Linaro, Ltd. <ard.biesheuvel@linaro.org>
 */

#ifdef CONFIG_ARM64
#include <asm/neon-intrinsics.h>

#define AES_ROUND	"aese %0.16b, %1.16b \n\t aesmc %0.16b, %0.16b"
#else
#include <arm_neon.h>

#define AES_ROUND	"aese.8 %q0, %q1 \n\t aesmc.8 %q0, %q0"
#endif

#define AEGIS_BLOCK_SIZE	16

#include <stddef.h>
#include "aegis-neon.h"

extern int aegis128_have_aes_insn;

void *memcpy(void *dest, const void *src, size_t n);

struct aegis128_state {
	uint8x16_t v[5];
};

extern const uint8_t crypto_aes_sbox[];

static struct aegis128_state aegis128_load_state_neon(const void *state)
{
	return (struct aegis128_state){ {
		vld1q_u8(state),
		vld1q_u8(state + 16),
		vld1q_u8(state + 32),
		vld1q_u8(state + 48),
		vld1q_u8(state + 64)
	} };
}

static void aegis128_save_state_neon(struct aegis128_state st, void *state)
{
	vst1q_u8(state, st.v[0]);
	vst1q_u8(state + 16, st.v[1]);
	vst1q_u8(state + 32, st.v[2]);
	vst1q_u8(state + 48, st.v[3]);
	vst1q_u8(state + 64, st.v[4]);
}

static inline __attribute__((always_inline))
uint8x16_t aegis_aes_round(uint8x16_t w)
{
	uint8x16_t z = {};

#ifdef CONFIG_ARM64
	if (!__builtin_expect(aegis128_have_aes_insn, 1)) {
		static const uint8_t shift_rows[] = {
			0x0, 0x5, 0xa, 0xf, 0x4, 0x9, 0xe, 0x3,
			0x8, 0xd, 0x2, 0x7, 0xc, 0x1, 0x6, 0xb,
		};
		static const uint8_t ror32by8[] = {
			0x1, 0x2, 0x3, 0x0, 0x5, 0x6, 0x7, 0x4,
			0x9, 0xa, 0xb, 0x8, 0xd, 0xe, 0xf, 0xc,
		};
		uint8x16_t v;

		// shift rows
		w = vqtbl1q_u8(w, vld1q_u8(shift_rows));

		// sub bytes
#ifndef CONFIG_CC_IS_GCC
		v = vqtbl4q_u8(vld1q_u8_x4(crypto_aes_sbox), w);
		v = vqtbx4q_u8(v, vld1q_u8_x4(crypto_aes_sbox + 0x40), w - 0x40);
		v = vqtbx4q_u8(v, vld1q_u8_x4(crypto_aes_sbox + 0x80), w - 0x80);
		v = vqtbx4q_u8(v, vld1q_u8_x4(crypto_aes_sbox + 0xc0), w - 0xc0);
#else
		asm("tbl %0.16b, {v16.16b-v19.16b}, %1.16b" : "=w"(v) : "w"(w));
		w -= 0x40;
		asm("tbx %0.16b, {v20.16b-v23.16b}, %1.16b" : "+w"(v) : "w"(w));
		w -= 0x40;
		asm("tbx %0.16b, {v24.16b-v27.16b}, %1.16b" : "+w"(v) : "w"(w));
		w -= 0x40;
		asm("tbx %0.16b, {v28.16b-v31.16b}, %1.16b" : "+w"(v) : "w"(w));
#endif

		// mix columns
		w = (v << 1) ^ (uint8x16_t)(((int8x16_t)v >> 7) & 0x1b);
		w ^= (uint8x16_t)vrev32q_u16((uint16x8_t)v);
		w ^= vqtbl1q_u8(v ^ w, vld1q_u8(ror32by8));

		return w;
	}
#endif

	/*
	 * We use inline asm here instead of the vaeseq_u8/vaesmcq_u8 intrinsics
	 * to force the compiler to issue the aese/aesmc instructions in pairs.
	 * This is much faster on many cores, where the instruction pair can
	 * execute in a single cycle.
	 */
	asm(AES_ROUND : "+w"(w) : "w"(z));
	return w;
}

static inline __attribute__((always_inline))
struct aegis128_state aegis128_update_neon(struct aegis128_state st,
					   uint8x16_t m)
{
	m       ^= aegis_aes_round(st.v[4]);
	st.v[4] ^= aegis_aes_round(st.v[3]);
	st.v[3] ^= aegis_aes_round(st.v[2]);
	st.v[2] ^= aegis_aes_round(st.v[1]);
	st.v[1] ^= aegis_aes_round(st.v[0]);
	st.v[0] ^= m;

	return st;
}

static inline __attribute__((always_inline))
void preload_sbox(void)
{
	if (!IS_ENABLED(CONFIG_ARM64) ||
	    !IS_ENABLED(CONFIG_CC_IS_GCC) ||
	    __builtin_expect(aegis128_have_aes_insn, 1))
		return;

	asm("ld1	{v16.16b-v19.16b}, [%0], #64	\n\t"
	    "ld1	{v20.16b-v23.16b}, [%0], #64	\n\t"
	    "ld1	{v24.16b-v27.16b}, [%0], #64	\n\t"
	    "ld1	{v28.16b-v31.16b}, [%0]		\n\t"
	    :: "r"(crypto_aes_sbox));
}

void crypto_aegis128_init_neon(void *state, const void *key, const void *iv)
{
	static const uint8_t const0[] = {
		0x00, 0x01, 0x01, 0x02, 0x03, 0x05, 0x08, 0x0d,
		0x15, 0x22, 0x37, 0x59, 0x90, 0xe9, 0x79, 0x62,
	};
	static const uint8_t const1[] = {
		0xdb, 0x3d, 0x18, 0x55, 0x6d, 0xc2, 0x2f, 0xf1,
		0x20, 0x11, 0x31, 0x42, 0x73, 0xb5, 0x28, 0xdd,
	};
	uint8x16_t k = vld1q_u8(key);
	uint8x16_t kiv = k ^ vld1q_u8(iv);
	struct aegis128_state st = {{
		kiv,
		vld1q_u8(const1),
		vld1q_u8(const0),
		k ^ vld1q_u8(const0),
		k ^ vld1q_u8(const1),
	}};
	int i;

	preload_sbox();

	for (i = 0; i < 5; i++) {
		st = aegis128_update_neon(st, k);
		st = aegis128_update_neon(st, kiv);
	}
	aegis128_save_state_neon(st, state);
}

void crypto_aegis128_update_neon(void *state, const void *msg)
{
	struct aegis128_state st = aegis128_load_state_neon(state);

	preload_sbox();

	st = aegis128_update_neon(st, vld1q_u8(msg));

	aegis128_save_state_neon(st, state);
}

#ifdef CONFIG_ARM
/*
 * AArch32 does not provide these intrinsics natively because it does not
 * implement the underlying instructions. AArch32 only provides 64-bit
 * wide vtbl.8/vtbx.8 instruction, so use those instead.
 */
static uint8x16_t vqtbl1q_u8(uint8x16_t a, uint8x16_t b)
{
	union {
		uint8x16_t	val;
		uint8x8x2_t	pair;
	} __a = { a };

	return vcombine_u8(vtbl2_u8(__a.pair, vget_low_u8(b)),
			   vtbl2_u8(__a.pair, vget_high_u8(b)));
}

static uint8x16_t vqtbx1q_u8(uint8x16_t v, uint8x16_t a, uint8x16_t b)
{
	union {
		uint8x16_t	val;
		uint8x8x2_t	pair;
	} __a = { a };

	return vcombine_u8(vtbx2_u8(vget_low_u8(v), __a.pair, vget_low_u8(b)),
			   vtbx2_u8(vget_high_u8(v), __a.pair, vget_high_u8(b)));
}

static int8_t vminvq_s8(int8x16_t v)
{
	int8x8_t s = vpmin_s8(vget_low_s8(v), vget_high_s8(v));

	s = vpmin_s8(s, s);
	s = vpmin_s8(s, s);
	s = vpmin_s8(s, s);

	return vget_lane_s8(s, 0);
}
#endif

static const uint8_t permute[] __aligned(64) = {
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
};

void crypto_aegis128_encrypt_chunk_neon(void *state, void *dst, const void *src,
					unsigned int size)
{
	struct aegis128_state st = aegis128_load_state_neon(state);
	const int short_input = size < AEGIS_BLOCK_SIZE;
	uint8x16_t msg;

	preload_sbox();

	while (size >= AEGIS_BLOCK_SIZE) {
		uint8x16_t s = st.v[1] ^ (st.v[2] & st.v[3]) ^ st.v[4];

		msg = vld1q_u8(src);
		st = aegis128_update_neon(st, msg);
		msg ^= s;
		vst1q_u8(dst, msg);

		size -= AEGIS_BLOCK_SIZE;
		src += AEGIS_BLOCK_SIZE;
		dst += AEGIS_BLOCK_SIZE;
	}

	if (size > 0) {
		uint8x16_t s = st.v[1] ^ (st.v[2] & st.v[3]) ^ st.v[4];
		uint8_t buf[AEGIS_BLOCK_SIZE];
		const void *in = src;
		void *out = dst;
		uint8x16_t m;

		if (__builtin_expect(short_input, 0))
			in = out = memcpy(buf + AEGIS_BLOCK_SIZE - size, src, size);

		m = vqtbl1q_u8(vld1q_u8(in + size - AEGIS_BLOCK_SIZE),
			       vld1q_u8(permute + 32 - size));

		st = aegis128_update_neon(st, m);

		vst1q_u8(out + size - AEGIS_BLOCK_SIZE,
			 vqtbl1q_u8(m ^ s, vld1q_u8(permute + size)));

		if (__builtin_expect(short_input, 0))
			memcpy(dst, out, size);
		else
			vst1q_u8(out - AEGIS_BLOCK_SIZE, msg);
	}

	aegis128_save_state_neon(st, state);
}

void crypto_aegis128_decrypt_chunk_neon(void *state, void *dst, const void *src,
					unsigned int size)
{
	struct aegis128_state st = aegis128_load_state_neon(state);
	const int short_input = size < AEGIS_BLOCK_SIZE;
	uint8x16_t msg;

	preload_sbox();

	while (size >= AEGIS_BLOCK_SIZE) {
		msg = vld1q_u8(src) ^ st.v[1] ^ (st.v[2] & st.v[3]) ^ st.v[4];
		st = aegis128_update_neon(st, msg);
		vst1q_u8(dst, msg);

		size -= AEGIS_BLOCK_SIZE;
		src += AEGIS_BLOCK_SIZE;
		dst += AEGIS_BLOCK_SIZE;
	}

	if (size > 0) {
		uint8x16_t s = st.v[1] ^ (st.v[2] & st.v[3]) ^ st.v[4];
		uint8_t buf[AEGIS_BLOCK_SIZE];
		const void *in = src;
		void *out = dst;
		uint8x16_t m;

		if (__builtin_expect(short_input, 0))
			in = out = memcpy(buf + AEGIS_BLOCK_SIZE - size, src, size);

		m = s ^ vqtbx1q_u8(s, vld1q_u8(in + size - AEGIS_BLOCK_SIZE),
				   vld1q_u8(permute + 32 - size));

		st = aegis128_update_neon(st, m);

		vst1q_u8(out + size - AEGIS_BLOCK_SIZE,
			 vqtbl1q_u8(m, vld1q_u8(permute + size)));

		if (__builtin_expect(short_input, 0))
			memcpy(dst, out, size);
		else
			vst1q_u8(out - AEGIS_BLOCK_SIZE, msg);
	}

	aegis128_save_state_neon(st, state);
}

int crypto_aegis128_final_neon(void *state, void *tag_xor,
			       unsigned int assoclen,
			       unsigned int cryptlen,
			       unsigned int authsize)
{
	struct aegis128_state st = aegis128_load_state_neon(state);
	uint8x16_t v;
	int i;

	preload_sbox();

	v = st.v[3] ^ (uint8x16_t)vcombine_u64(vmov_n_u64(8ULL * assoclen),
					       vmov_n_u64(8ULL * cryptlen));

	for (i = 0; i < 7; i++)
		st = aegis128_update_neon(st, v);

	v = st.v[0] ^ st.v[1] ^ st.v[2] ^ st.v[3] ^ st.v[4];

	if (authsize > 0) {
		v = vqtbl1q_u8(~vceqq_u8(v, vld1q_u8(tag_xor)),
			       vld1q_u8(permute + authsize));

		return vminvq_s8((int8x16_t)v);
	}

	vst1q_u8(tag_xor, v);
	return 0;
}