aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm/lib/sha1.S
blob: eb0edb80d7b84c8780168bd51b535b827dadba1d (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
/*
 *  linux/arch/arm/lib/sha1.S
 *
 *  SHA transform optimized for ARM
 *
 *  Copyright:	(C) 2005 by Nicolas Pitre <nico@fluxnic.net>
 *  Created:	September 17, 2005
 *
 *  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.
 *
 *  The reference implementation for this code is linux/lib/sha1.c
 */

#include <linux/linkage.h>

	.text


/*
 * void sha_transform(__u32 *digest, const char *in, __u32 *W)
 *
 * Note: the "in" ptr may be unaligned.
 */

ENTRY(sha_transform)

	stmfd	sp!, {r4 - r8, lr}

	@ for (i = 0; i < 16; i++)
	@         W[i] = be32_to_cpu(in[i]);

#ifdef __ARMEB__
	mov	r4, r0
	mov	r0, r2
	mov	r2, #64
	bl	memcpy
	mov	r2, r0
	mov	r0, r4
#else
	mov	r3, r2
	mov	lr, #16
1:	ldrb	r4, [r1], #1
	ldrb	r5, [r1], #1
	ldrb	r6, [r1], #1
	ldrb	r7, [r1], #1
	subs	lr, lr, #1
	orr	r5, r5, r4, lsl #8
	orr	r6, r6, r5, lsl #8
	orr	r7, r7, r6, lsl #8
	str	r7, [r3], #4
	bne	1b
#endif

	@ for (i = 0; i < 64; i++)
	@         W[i+16] = ror(W[i+13] ^ W[i+8] ^ W[i+2] ^ W[i], 31);

	sub	r3, r2, #4
	mov	lr, #64
2:	ldr	r4, [r3, #4]!
	subs	lr, lr, #1
	ldr	r5, [r3, #8]
	ldr	r6, [r3, #32]
	ldr	r7, [r3, #52]
	eor	r4, r4, r5
	eor	r4, r4, r6
	eor	r4, r4, r7
	mov	r4, r4, ror #31
	str	r4, [r3, #64]
	bne	2b

	/*
	 * The SHA functions are:
	 *
	 * f1(B,C,D) = (D ^ (B & (C ^ D)))
	 * f2(B,C,D) = (B ^ C ^ D)
	 * f3(B,C,D) = ((B & C) | (D & (B | C)))
	 *
	 * Then the sub-blocks are processed as follows:
	 *
	 * A' = ror(A, 27) + f(B,C,D) + E + K + *W++
	 * B' = A
	 * C' = ror(B, 2)
	 * D' = C
	 * E' = D
	 *
	 * We therefore unroll each loop 5 times to avoid register shuffling.
	 * Also the ror for C (and also D and E which are successivelyderived
	 * from it) is applied in place to cut on an additional mov insn for
	 * each round.
	 */

	.macro	sha_f1, A, B, C, D, E
	ldr	r3, [r2], #4
	eor	ip, \C, \D
	add	\E, r1, \E, ror #2
	and	ip, \B, ip, ror #2
	add	\E, \E, \A, ror #27
	eor	ip, ip, \D, ror #2
	add	\E, \E, r3
	add	\E, \E, ip
	.endm

	.macro	sha_f2, A, B, C, D, E
	ldr	r3, [r2], #4
	add	\E, r1, \E, ror #2
	eor	ip, \B, \C, ror #2
	add	\E, \E, \A, ror #27
	eor	ip, ip, \D, ror #2
	add	\E, \E, r3
	add	\E, \E, ip
	.endm

	.macro	sha_f3, A, B, C, D, E
	ldr	r3, [r2], #4
	add	\E, r1, \E, ror #2
	orr	ip, \B, \C, ror #2
	add	\E, \E, \A, ror #27
	and	ip, ip, \D, ror #2
	add	\E, \E, r3
	and	r3, \B, \C, ror #2
	orr	ip, ip, r3
	add	\E, \E, ip
	.endm

	ldmia	r0, {r4 - r8}

	mov	lr, #4
	ldr	r1, .L_sha_K + 0

	/* adjust initial values */
	mov	r6, r6, ror #30
	mov	r7, r7, ror #30
	mov	r8, r8, ror #30

3:	subs	lr, lr, #1
	sha_f1	r4, r5, r6, r7, r8
	sha_f1	r8, r4, r5, r6, r7
	sha_f1	r7, r8, r4, r5, r6
	sha_f1	r6, r7, r8, r4, r5
	sha_f1	r5, r6, r7, r8, r4
	bne	3b

	ldr	r1, .L_sha_K + 4
	mov	lr, #4

4:	subs	lr, lr, #1
	sha_f2	r4, r5, r6, r7, r8
	sha_f2	r8, r4, r5, r6, r7
	sha_f2	r7, r8, r4, r5, r6
	sha_f2	r6, r7, r8, r4, r5
	sha_f2	r5, r6, r7, r8, r4
	bne	4b

	ldr	r1, .L_sha_K + 8
	mov	lr, #4

5:	subs	lr, lr, #1
	sha_f3	r4, r5, r6, r7, r8
	sha_f3	r8, r4, r5, r6, r7
	sha_f3	r7, r8, r4, r5, r6
	sha_f3	r6, r7, r8, r4, r5
	sha_f3	r5, r6, r7, r8, r4
	bne	5b

	ldr	r1, .L_sha_K + 12
	mov	lr, #4

6:	subs	lr, lr, #1
	sha_f2	r4, r5, r6, r7, r8
	sha_f2	r8, r4, r5, r6, r7
	sha_f2	r7, r8, r4, r5, r6
	sha_f2	r6, r7, r8, r4, r5
	sha_f2	r5, r6, r7, r8, r4
	bne	6b

	ldmia	r0, {r1, r2, r3, ip, lr}
	add	r4, r1, r4
	add	r5, r2, r5
	add	r6, r3, r6, ror #2
	add	r7, ip, r7, ror #2
	add	r8, lr, r8, ror #2
	stmia	r0, {r4 - r8}

	ldmfd	sp!, {r4 - r8, pc}

ENDPROC(sha_transform)

	.align	2
.L_sha_K:
	.word	0x5a827999, 0x6ed9eba1, 0x8f1bbcdc, 0xca62c1d6


/*
 * void sha_init(__u32 *buf)
 */

	.align	2
.L_sha_initial_digest:
	.word	0x67452301, 0xefcdab89, 0x98badcfe, 0x10325476, 0xc3d2e1f0

ENTRY(sha_init)

	str	lr, [sp, #-4]!
	adr	r1, .L_sha_initial_digest
	ldmia	r1, {r1, r2, r3, ip, lr}
	stmia	r0, {r1, r2, r3, ip, lr}
	ldr	pc, [sp], #4

ENDPROC(sha_init)