aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/crypto/ghash-clmulni-intel_asm.S
blob: 71768d543dbb4f3fc6de5a6e97cea5de83900f05 (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
/*
 * Accelerated GHASH implementation with Intel PCLMULQDQ-NI
 * instructions. This file contains accelerated part of ghash
 * implementation. More information about PCLMULQDQ can be found at:
 *
 * http://software.intel.com/en-us/articles/carry-less-multiplication-and-its-usage-for-computing-the-gcm-mode/
 *
 * Copyright (c) 2009 Intel Corp.
 *   Author: Huang Ying <ying.huang@intel.com>
 *	     Vinodh Gopal
 *	     Erdinc Ozturk
 *	     Deniz Karakoyunlu
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation.
 */

#include <linux/linkage.h>

.align 16
.Lbswap_mask:
	.octa 0x000102030405060708090a0b0c0d0e0f
.Lpoly:
	.octa 0xc2000000000000000000000000000001
.Ltwo_one:
	.octa 0x00000001000000000000000000000001

#define DATA	%xmm0
#define SHASH	%xmm1
#define T1	%xmm2
#define T2	%xmm3
#define T3	%xmm4
#define BSWAP	%xmm5
#define IN1	%xmm6

.text

/*
 * __clmul_gf128mul_ble:	internal ABI
 * input:
 *	DATA:			operand1
 *	SHASH:			operand2, hash_key << 1 mod poly
 * output:
 *	DATA:			operand1 * operand2 mod poly
 * changed:
 *	T1
 *	T2
 *	T3
 */
__clmul_gf128mul_ble:
	movaps DATA, T1
	pshufd $0b01001110, DATA, T2
	pshufd $0b01001110, SHASH, T3
	pxor DATA, T2
	pxor SHASH, T3

	# pclmulqdq $0x00, SHASH, DATA	# DATA = a0 * b0
	.byte 0x66, 0x0f, 0x3a, 0x44, 0xc1, 0x00
	# pclmulqdq $0x11, SHASH, T1	# T1 = a1 * b1
	.byte 0x66, 0x0f, 0x3a, 0x44, 0xd1, 0x11
	# pclmulqdq $0x00, T3, T2	# T2 = (a1 + a0) * (b1 + b0)
	.byte 0x66, 0x0f, 0x3a, 0x44, 0xdc, 0x00
	pxor DATA, T2
	pxor T1, T2			# T2 = a0 * b1 + a1 * b0

	movaps T2, T3
	pslldq $8, T3
	psrldq $8, T2
	pxor T3, DATA
	pxor T2, T1			# <T1:DATA> is result of
					# carry-less multiplication

	# first phase of the reduction
	movaps DATA, T3
	psllq $1, T3
	pxor DATA, T3
	psllq $5, T3
	pxor DATA, T3
	psllq $57, T3
	movaps T3, T2
	pslldq $8, T2
	psrldq $8, T3
	pxor T2, DATA
	pxor T3, T1

	# second phase of the reduction
	movaps DATA, T2
	psrlq $5, T2
	pxor DATA, T2
	psrlq $1, T2
	pxor DATA, T2
	psrlq $1, T2
	pxor T2, T1
	pxor T1, DATA
	ret

/* void clmul_ghash_mul(char *dst, const be128 *shash) */
ENTRY(clmul_ghash_mul)
	movups (%rdi), DATA
	movups (%rsi), SHASH
	movaps .Lbswap_mask, BSWAP
	# pshufb BSWAP, DATA
	.byte 0x66, 0x0f, 0x38, 0x00, 0xc5
	call __clmul_gf128mul_ble
	# pshufb BSWAP, DATA
	.byte 0x66, 0x0f, 0x38, 0x00, 0xc5
	movups DATA, (%rdi)
	ret

/*
 * void clmul_ghash_update(char *dst, const char *src, unsigned int srclen,
 *			   const be128 *shash);
 */
ENTRY(clmul_ghash_update)
	cmp $16, %rdx
	jb .Lupdate_just_ret	# check length
	movaps .Lbswap_mask, BSWAP
	movups (%rdi), DATA
	movups (%rcx), SHASH
	# pshufb BSWAP, DATA
	.byte 0x66, 0x0f, 0x38, 0x00, 0xc5
.align 4
.Lupdate_loop:
	movups (%rsi), IN1
	# pshufb BSWAP, IN1
	.byte 0x66, 0x0f, 0x38, 0x00, 0xf5
	pxor IN1, DATA
	call __clmul_gf128mul_ble
	sub $16, %rdx
	add $16, %rsi
	cmp $16, %rdx
	jge .Lupdate_loop
	# pshufb BSWAP, DATA
	.byte 0x66, 0x0f, 0x38, 0x00, 0xc5
	movups DATA, (%rdi)
.Lupdate_just_ret:
	ret

/*
 * void clmul_ghash_setkey(be128 *shash, const u8 *key);
 *
 * Calculate hash_key << 1 mod poly
 */
ENTRY(clmul_ghash_setkey)
	movaps .Lbswap_mask, BSWAP
	movups (%rsi), %xmm0
	# pshufb BSWAP, %xmm0
	.byte 0x66, 0x0f, 0x38, 0x00, 0xc5
	movaps %xmm0, %xmm1
	psllq $1, %xmm0
	psrlq $63, %xmm1
	movaps %xmm1, %xmm2
	pslldq $8, %xmm1
	psrldq $8, %xmm2
	por %xmm1, %xmm0
	# reduction
	pshufd $0b00100100, %xmm2, %xmm1
	pcmpeqd .Ltwo_one, %xmm1
	pand .Lpoly, %xmm1
	pxor %xmm1, %xmm0
	movups %xmm0, (%rdi)
	ret