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
|
C nettle, low-level cryptographics library
C
C Copyright (C) 2013 Niels Möller
C
C The nettle library is free software; you can redistribute it and/or modify
C it under the terms of the GNU Lesser General Public License as published by
C the Free Software Foundation; either version 2.1 of the License, or (at your
C option) any later version.
C
C The nettle library is distributed in the hope that it will be useful, but
C WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
C or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
C License for more details.
C
C You should have received a copy of the GNU Lesser General Public License
C along with the nettle library; see the file COPYING.LIB. If not, write to
C the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
C MA 02111-1301, USA.
.file "salsa20-core-internal.asm"
.fpu neon
define(<DST>, <r0>)
define(<SRC>, <r1>)
define(<ROUNDS>, <r2>)
define(<X0>, <q0>)
define(<X1>, <q1>)
define(<X2>, <q2>)
define(<X3>, <q3>)
define(<T0>, <q8>)
define(<T1>, <q9>)
define(<M0101>, <q10>)
define(<M0110>, <q11>)
define(<M0011>, <q12>)
define(<S1>, <q13>)
define(<S2>, <q14>)
define(<S3>, <q15>)
define(<QROUND>, <
vadd.i32 T0, $1, $4
vshl.i32 T1, T0, #7
vshr.u32 T0, T0, #25
veor $2, $2, T0
veor $2, $2, T1
vadd.i32 T0, $1, $2
vshl.i32 T1, T0, #9
vshr.u32 T0, T0, #23
veor $3, $3, T0
veor $3, $3, T1
vadd.i32 T0, $2, $3
vshl.i32 T1, T0, #13
vshr.u32 T0, T0, #19
veor $4, $4, T0
veor $4, $4, T1
vadd.i32 T0, $3, $4
vshl.i32 T1, T0, #18
vshr.u32 T0, T0, #14
veor $1, $1, T0
veor $1, $1, T1
>)
.text
.align 4
.Lmasks:
.int 0,-1, 0,-1
.int 0,-1,-1, 0
.int 0, 0,-1,-1
C _salsa20_core(uint32_t *dst, const uint32_t *src, unsigned rounds)
PROLOGUE(_nettle_salsa20_core)
vldm SRC, {X0,X1,X2,X3}
C Input rows:
C 0 1 2 3 X0
C 4 5 6 7 X1
C 8 9 10 11 X2
C 12 13 14 15 X3
C Permuted to:
C 0 5 10 15
C 4 9 14 3
C 8 13 2 7
C 12 1 6 11
C FIXME: Construct in some other way?
adr r12, .Lmasks
vldm r12, {M0101, M0110, M0011}
vmov S1, X1
vmov S2, X2
vmov S3, X3
C Swaps in columns 1, 3:
C 0 5 2 7 X0 ^
C 4 1 6 3 T0 v
C 8 13 10 15 T1 ^
C 12 9 14 11 X3 v
vmov T0, X1
vmov T1, X2
vbit T0, X0, M0101
vbit X0, X1, M0101
vbit T1, X3, M0101
vbit X3, X2, M0101
C Swaps in column 1, 2:
C 0 5 2 7 X0
C 4 9 14 3 X1 ^
C 8 13 10 15 T1 |
C 12 1 6 11 X3 v
vmov X1, T0
vbit X1, X3, M0110
vbit X3, T0, M0110
C Swaps in columm 2,3:
C 0 5 10 15 X0 ^
C 4 9 14 3 X1 |
C 8 13 2 7 X2 v
C 12 1 6 11 X3
vmov X2, T1
vbit X2, X0, M0011
vbit X0, T1, M0011
.Loop:
QROUND(X0, X1, X2, X3)
C Rotate rows, to get
C 0 5 10 15
C 3 4 9 14 >>> 1
C 2 7 8 13 >>> 2
C 1 6 11 12 >>> 3
vext.32 X1, X1, X1, #3
vext.32 X2, X2, X2, #2
vext.32 X3, X3, X3, #1
QROUND(X0, X3, X2, X1)
subs ROUNDS, ROUNDS, #2
C Inverse rotation
vext.32 X1, X1, X1, #1
vext.32 X2, X2, X2, #2
vext.32 X3, X3, X3, #3
bhi .Loop
C Inverse swaps
vmov T1, X2
vbit T1, X0, M0011
vbit X0, X2, M0011
vmov T0, X1
vbit T0, X3, M0110
vbit X3, X1, M0110
vmov X1, T0
vmov X2, T1
vbit X1, X0, M0101
vbit X0, T0, M0101
vbit X2, X3, M0101
vbit X3, T1, M0101
vld1.64 {T0}, [SRC]
vadd.u32 X0, X0, T0
vadd.u32 X1, X1, S1
vadd.u32 X2, X2, S2
vadd.u32 X3, X3, S3
vstm DST, {X0,X1,X2,X3}
bx lr
EPILOGUE(_nettle_salsa20_core)
divert(-1)
define salsastate
p/x $q0.u32
p/x $q1.u32
p/x $q2.u32
p/x $q3.u32
end
|
