summaryrefslogtreecommitdiffstats
path: root/lib/siphash.c
blob: 3ae58b4edad61527317f6a2b68f0343f8a654683 (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
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
/* Copyright (C) 2016 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
 *
 * This file is provided under a dual BSD/GPLv2 license.
 *
 * SipHash: a fast short-input PRF
 * https://131002.net/siphash/
 *
 * This implementation is specifically for SipHash2-4 for a secure PRF
 * and HalfSipHash1-3/SipHash1-3 for an insecure PRF only suitable for
 * hashtables.
 */

#include <linux/siphash.h>
#include <asm/unaligned.h>

#if defined(CONFIG_DCACHE_WORD_ACCESS) && BITS_PER_LONG == 64
#include <linux/dcache.h>
#include <asm/word-at-a-time.h>
#endif

#define SIPROUND \
	do { \
	v0 += v1; v1 = rol64(v1, 13); v1 ^= v0; v0 = rol64(v0, 32); \
	v2 += v3; v3 = rol64(v3, 16); v3 ^= v2; \
	v0 += v3; v3 = rol64(v3, 21); v3 ^= v0; \
	v2 += v1; v1 = rol64(v1, 17); v1 ^= v2; v2 = rol64(v2, 32); \
	} while (0)

#define PREAMBLE(len) \
	u64 v0 = 0x736f6d6570736575ULL; \
	u64 v1 = 0x646f72616e646f6dULL; \
	u64 v2 = 0x6c7967656e657261ULL; \
	u64 v3 = 0x7465646279746573ULL; \
	u64 b = ((u64)(len)) << 56; \
	v3 ^= key->key[1]; \
	v2 ^= key->key[0]; \
	v1 ^= key->key[1]; \
	v0 ^= key->key[0];

#define POSTAMBLE \
	v3 ^= b; \
	SIPROUND; \
	SIPROUND; \
	v0 ^= b; \
	v2 ^= 0xff; \
	SIPROUND; \
	SIPROUND; \
	SIPROUND; \
	SIPROUND; \
	return (v0 ^ v1) ^ (v2 ^ v3);

u64 __siphash_aligned(const void *data, size_t len, const siphash_key_t *key)
{
	const u8 *end = data + len - (len % sizeof(u64));
	const u8 left = len & (sizeof(u64) - 1);
	u64 m;
	PREAMBLE(len)
	for (; data != end; data += sizeof(u64)) {
		m = le64_to_cpup(data);
		v3 ^= m;
		SIPROUND;
		SIPROUND;
		v0 ^= m;
	}
#if defined(CONFIG_DCACHE_WORD_ACCESS) && BITS_PER_LONG == 64
	if (left)
		b |= le64_to_cpu((__force __le64)(load_unaligned_zeropad(data) &
						  bytemask_from_count(left)));
#else
	switch (left) {
	case 7: b |= ((u64)end[6]) << 48;
	case 6: b |= ((u64)end[5]) << 40;
	case 5: b |= ((u64)end[4]) << 32;
	case 4: b |= le32_to_cpup(data); break;
	case 3: b |= ((u64)end[2]) << 16;
	case 2: b |= le16_to_cpup(data); break;
	case 1: b |= end[0];
	}
#endif
	POSTAMBLE
}
EXPORT_SYMBOL(__siphash_aligned);

#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
u64 __siphash_unaligned(const void *data, size_t len, const siphash_key_t *key)
{
	const u8 *end = data + len - (len % sizeof(u64));
	const u8 left = len & (sizeof(u64) - 1);
	u64 m;
	PREAMBLE(len)
	for (; data != end; data += sizeof(u64)) {
		m = get_unaligned_le64(data);
		v3 ^= m;
		SIPROUND;
		SIPROUND;
		v0 ^= m;
	}
#if defined(CONFIG_DCACHE_WORD_ACCESS) && BITS_PER_LONG == 64
	if (left)
		b |= le64_to_cpu((__force __le64)(load_unaligned_zeropad(data) &
						  bytemask_from_count(left)));
#else
	switch (left) {
	case 7: b |= ((u64)end[6]) << 48;
	case 6: b |= ((u64)end[5]) << 40;
	case 5: b |= ((u64)end[4]) << 32;
	case 4: b |= get_unaligned_le32(end); break;
	case 3: b |= ((u64)end[2]) << 16;
	case 2: b |= get_unaligned_le16(end); break;
	case 1: b |= end[0];
	}
#endif
	POSTAMBLE
}
EXPORT_SYMBOL(__siphash_unaligned);
#endif

/**
 * siphash_1u64 - compute 64-bit siphash PRF value of a u64
 * @first: first u64
 * @key: the siphash key
 */
u64 siphash_1u64(const u64 first, const siphash_key_t *key)
{
	PREAMBLE(8)
	v3 ^= first;
	SIPROUND;
	SIPROUND;
	v0 ^= first;
	POSTAMBLE
}
EXPORT_SYMBOL(siphash_1u64);

/**
 * siphash_2u64 - compute 64-bit siphash PRF value of 2 u64
 * @first: first u64
 * @second: second u64
 * @key: the siphash key
 */
u64 siphash_2u64(const u64 first, const u64 second, const siphash_key_t *key)
{
	PREAMBLE(16)
	v3 ^= first;
	SIPROUND;
	SIPROUND;
	v0 ^= first;
	v3 ^= second;
	SIPROUND;
	SIPROUND;
	v0 ^= second;
	POSTAMBLE
}
EXPORT_SYMBOL(siphash_2u64);

/**
 * siphash_3u64 - compute 64-bit siphash PRF value of 3 u64
 * @first: first u64
 * @second: second u64
 * @third: third u64
 * @key: the siphash key
 */
u64 siphash_3u64(const u64 first, const u64 second, const u64 third,
		 const siphash_key_t *key)
{
	PREAMBLE(24)
	v3 ^= first;
	SIPROUND;
	SIPROUND;
	v0 ^= first;
	v3 ^= second;
	SIPROUND;
	SIPROUND;
	v0 ^= second;
	v3 ^= third;
	SIPROUND;
	SIPROUND;
	v0 ^= third;
	POSTAMBLE
}
EXPORT_SYMBOL(siphash_3u64);

/**
 * siphash_4u64 - compute 64-bit siphash PRF value of 4 u64
 * @first: first u64
 * @second: second u64
 * @third: third u64
 * @forth: forth u64
 * @key: the siphash key
 */
u64 siphash_4u64(const u64 first, const u64 second, const u64 third,
		 const u64 forth, const siphash_key_t *key)
{
	PREAMBLE(32)
	v3 ^= first;
	SIPROUND;
	SIPROUND;
	v0 ^= first;
	v3 ^= second;
	SIPROUND;
	SIPROUND;
	v0 ^= second;
	v3 ^= third;
	SIPROUND;
	SIPROUND;
	v0 ^= third;
	v3 ^= forth;
	SIPROUND;
	SIPROUND;
	v0 ^= forth;
	POSTAMBLE
}
EXPORT_SYMBOL(siphash_4u64);

u64 siphash_1u32(const u32 first, const siphash_key_t *key)
{
	PREAMBLE(4)
	b |= first;
	POSTAMBLE
}
EXPORT_SYMBOL(siphash_1u32);

u64 siphash_3u32(const u32 first, const u32 second, const u32 third,
		 const siphash_key_t *key)
{
	u64 combined = (u64)second << 32 | first;
	PREAMBLE(12)
	v3 ^= combined;
	SIPROUND;
	SIPROUND;
	v0 ^= combined;
	b |= third;
	POSTAMBLE
}
EXPORT_SYMBOL(siphash_3u32);

#if BITS_PER_LONG == 64
/* Note that on 64-bit, we make HalfSipHash1-3 actually be SipHash1-3, for
 * performance reasons. On 32-bit, below, we actually implement HalfSipHash1-3.
 */

#define HSIPROUND SIPROUND
#define HPREAMBLE(len) PREAMBLE(len)
#define HPOSTAMBLE \
	v3 ^= b; \
	HSIPROUND; \
	v0 ^= b; \
	v2 ^= 0xff; \
	HSIPROUND; \
	HSIPROUND; \
	HSIPROUND; \
	return (v0 ^ v1) ^ (v2 ^ v3);

u32 __hsiphash_aligned(const void *data, size_t len, const hsiphash_key_t *key)
{
	const u8 *end = data + len - (len % sizeof(u64));
	const u8 left = len & (sizeof(u64) - 1);
	u64 m;
	HPREAMBLE(len)
	for (; data != end; data += sizeof(u64)) {
		m = le64_to_cpup(data);
		v3 ^= m;
		HSIPROUND;
		v0 ^= m;
	}
#if defined(CONFIG_DCACHE_WORD_ACCESS) && BITS_PER_LONG == 64
	if (left)
		b |= le64_to_cpu((__force __le64)(load_unaligned_zeropad(data) &
						  bytemask_from_count(left)));
#else
	switch (left) {
	case 7: b |= ((u64)end[6]) << 48;
	case 6: b |= ((u64)end[5]) << 40;
	case 5: b |= ((u64)end[4]) << 32;
	case 4: b |= le32_to_cpup(data); break;
	case 3: b |= ((u64)end[2]) << 16;
	case 2: b |= le16_to_cpup(data); break;
	case 1: b |= end[0];
	}
#endif
	HPOSTAMBLE
}
EXPORT_SYMBOL(__hsiphash_aligned);

#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
u32 __hsiphash_unaligned(const void *data, size_t len,
			 const hsiphash_key_t *key)
{
	const u8 *end = data + len - (len % sizeof(u64));
	const u8 left = len & (sizeof(u64) - 1);
	u64 m;
	HPREAMBLE(len)
	for (; data != end; data += sizeof(u64)) {
		m = get_unaligned_le64(data);
		v3 ^= m;
		HSIPROUND;
		v0 ^= m;
	}
#if defined(CONFIG_DCACHE_WORD_ACCESS) && BITS_PER_LONG == 64
	if (left)
		b |= le64_to_cpu((__force __le64)(load_unaligned_zeropad(data) &
						  bytemask_from_count(left)));
#else
	switch (left) {
	case 7: b |= ((u64)end[6]) << 48;
	case 6: b |= ((u64)end[5]) << 40;
	case 5: b |= ((u64)end[4]) << 32;
	case 4: b |= get_unaligned_le32(end); break;
	case 3: b |= ((u64)end[2]) << 16;
	case 2: b |= get_unaligned_le16(end); break;
	case 1: b |= end[0];
	}
#endif
	HPOSTAMBLE
}
EXPORT_SYMBOL(__hsiphash_unaligned);
#endif

/**
 * hsiphash_1u32 - compute 64-bit hsiphash PRF value of a u32
 * @first: first u32
 * @key: the hsiphash key
 */
u32 hsiphash_1u32(const u32 first, const hsiphash_key_t *key)
{
	HPREAMBLE(4)
	b |= first;
	HPOSTAMBLE
}
EXPORT_SYMBOL(hsiphash_1u32);

/**
 * hsiphash_2u32 - compute 32-bit hsiphash PRF value of 2 u32
 * @first: first u32
 * @second: second u32
 * @key: the hsiphash key
 */
u32 hsiphash_2u32(const u32 first, const u32 second, const hsiphash_key_t *key)
{
	u64 combined = (u64)second << 32 | first;
	HPREAMBLE(8)
	v3 ^= combined;
	HSIPROUND;
	v0 ^= combined;
	HPOSTAMBLE
}
EXPORT_SYMBOL(hsiphash_2u32);

/**
 * hsiphash_3u32 - compute 32-bit hsiphash PRF value of 3 u32
 * @first: first u32
 * @second: second u32
 * @third: third u32
 * @key: the hsiphash key
 */
u32 hsiphash_3u32(const u32 first, const u32 second, const u32 third,
		  const hsiphash_key_t *key)
{
	u64 combined = (u64)second << 32 | first;
	HPREAMBLE(12)
	v3 ^= combined;
	HSIPROUND;
	v0 ^= combined;
	b |= third;
	HPOSTAMBLE
}
EXPORT_SYMBOL(hsiphash_3u32);

/**
 * hsiphash_4u32 - compute 32-bit hsiphash PRF value of 4 u32
 * @first: first u32
 * @second: second u32
 * @third: third u32
 * @forth: forth u32
 * @key: the hsiphash key
 */
u32 hsiphash_4u32(const u32 first, const u32 second, const u32 third,
		  const u32 forth, const hsiphash_key_t *key)
{
	u64 combined = (u64)second << 32 | first;
	HPREAMBLE(16)
	v3 ^= combined;
	HSIPROUND;
	v0 ^= combined;
	combined = (u64)forth << 32 | third;
	v3 ^= combined;
	HSIPROUND;
	v0 ^= combined;
	HPOSTAMBLE
}
EXPORT_SYMBOL(hsiphash_4u32);
#else
#define HSIPROUND \
	do { \
	v0 += v1; v1 = rol32(v1, 5); v1 ^= v0; v0 = rol32(v0, 16); \
	v2 += v3; v3 = rol32(v3, 8); v3 ^= v2; \
	v0 += v3; v3 = rol32(v3, 7); v3 ^= v0; \
	v2 += v1; v1 = rol32(v1, 13); v1 ^= v2; v2 = rol32(v2, 16); \
	} while (0)

#define HPREAMBLE(len) \
	u32 v0 = 0; \
	u32 v1 = 0; \
	u32 v2 = 0x6c796765U; \
	u32 v3 = 0x74656462U; \
	u32 b = ((u32)(len)) << 24; \
	v3 ^= key->key[1]; \
	v2 ^= key->key[0]; \
	v1 ^= key->key[1]; \
	v0 ^= key->key[0];

#define HPOSTAMBLE \
	v3 ^= b; \
	HSIPROUND; \
	v0 ^= b; \
	v2 ^= 0xff; \
	HSIPROUND; \
	HSIPROUND; \
	HSIPROUND; \
	return v1 ^ v3;

u32 __hsiphash_aligned(const void *data, size_t len, const hsiphash_key_t *key)
{
	const u8 *end = data + len - (len % sizeof(u32));
	const u8 left = len & (sizeof(u32) - 1);
	u32 m;
	HPREAMBLE(len)
	for (; data != end; data += sizeof(u32)) {
		m = le32_to_cpup(data);
		v3 ^= m;
		HSIPROUND;
		v0 ^= m;
	}
	switch (left) {
	case 3: b |= ((u32)end[2]) << 16;
	case 2: b |= le16_to_cpup(data); break;
	case 1: b |= end[0];
	}
	HPOSTAMBLE
}
EXPORT_SYMBOL(__hsiphash_aligned);

#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
u32 __hsiphash_unaligned(const void *data, size_t len,
			 const hsiphash_key_t *key)
{
	const u8 *end = data + len - (len % sizeof(u32));
	const u8 left = len & (sizeof(u32) - 1);
	u32 m;
	HPREAMBLE(len)
	for (; data != end; data += sizeof(u32)) {
		m = get_unaligned_le32(data);
		v3 ^= m;
		HSIPROUND;
		v0 ^= m;
	}
	switch (left) {
	case 3: b |= ((u32)end[2]) << 16;
	case 2: b |= get_unaligned_le16(end); break;
	case 1: b |= end[0];
	}
	HPOSTAMBLE
}
EXPORT_SYMBOL(__hsiphash_unaligned);
#endif

/**
 * hsiphash_1u32 - compute 32-bit hsiphash PRF value of a u32
 * @first: first u32
 * @key: the hsiphash key
 */
u32 hsiphash_1u32(const u32 first, const hsiphash_key_t *key)
{
	HPREAMBLE(4)
	v3 ^= first;
	HSIPROUND;
	v0 ^= first;
	HPOSTAMBLE
}
EXPORT_SYMBOL(hsiphash_1u32);

/**
 * hsiphash_2u32 - compute 32-bit hsiphash PRF value of 2 u32
 * @first: first u32
 * @second: second u32
 * @key: the hsiphash key
 */
u32 hsiphash_2u32(const u32 first, const u32 second, const hsiphash_key_t *key)
{
	HPREAMBLE(8)
	v3 ^= first;
	HSIPROUND;
	v0 ^= first;
	v3 ^= second;
	HSIPROUND;
	v0 ^= second;
	HPOSTAMBLE
}
EXPORT_SYMBOL(hsiphash_2u32);

/**
 * hsiphash_3u32 - compute 32-bit hsiphash PRF value of 3 u32
 * @first: first u32
 * @second: second u32
 * @third: third u32
 * @key: the hsiphash key
 */
u32 hsiphash_3u32(const u32 first, const u32 second, const u32 third,
		  const hsiphash_key_t *key)
{
	HPREAMBLE(12)
	v3 ^= first;
	HSIPROUND;
	v0 ^= first;
	v3 ^= second;
	HSIPROUND;
	v0 ^= second;
	v3 ^= third;
	HSIPROUND;
	v0 ^= third;
	HPOSTAMBLE
}
EXPORT_SYMBOL(hsiphash_3u32);

/**
 * hsiphash_4u32 - compute 32-bit hsiphash PRF value of 4 u32
 * @first: first u32
 * @second: second u32
 * @third: third u32
 * @forth: forth u32
 * @key: the hsiphash key
 */
u32 hsiphash_4u32(const u32 first, const u32 second, const u32 third,
		  const u32 forth, const hsiphash_key_t *key)
{
	HPREAMBLE(16)
	v3 ^= first;
	HSIPROUND;
	v0 ^= first;
	v3 ^= second;
	HSIPROUND;
	v0 ^= second;
	v3 ^= third;
	HSIPROUND;
	v0 ^= third;
	v3 ^= forth;
	HSIPROUND;
	v0 ^= forth;
	HPOSTAMBLE
}
EXPORT_SYMBOL(hsiphash_4u32);
#endif
OpenPOWER on IntegriCloud