aes.asm 9 KB
Newer Older
1
! -*- mode: asm; asm-comment-char: ?!; -*-  
Niels Möller's avatar
Niels Möller committed
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
! nettle, low-level cryptographics library
! 
! Copyright (C) 2002 Niels Mller
!  
! The nettle library is free software; you can redistribute it and/or modify
! it under the terms of the GNU Lesser General Public License as published by
! the Free Software Foundation; either version 2.1 of the License, or (at your
! option) any later version.
! 
! The nettle library is distributed in the hope that it will be useful, but
! WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
! or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
! License for more details.
! 
! You should have received a copy of the GNU Lesser General Public License
! along with the nettle library; see the file COPYING.LIB.  If not, write to
! the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
! MA 02111-1307, USA.

21
22
! NOTE: Some of the %g registers are reserved for operating system etc
! (see gcc/config/sparc.h). We should use only %g1-%g3 to be safe.
Niels Möller's avatar
Niels Möller committed
23
	
24
	! Used registers:	%l0,1,2,3,4,5,6,7
25
26
	!			%i0,1,2,3,4 (%i6=%fp, %i7 = return)
	!			%o0,1,2,3,4,7 (%o6=%sp)
27
	!			%g1,2,3,5
Niels Möller's avatar
Niels Möller committed
28
	
29
	.file	"aes.asm"
Niels Möller's avatar
Niels Möller committed
30
	
31
! Arguments
32
define(ctx, %i0)
33
define(T, %i1)
34
define(length, %i2)
35
define(dst, %i3)
36
define(src, %i4)
37

38
! Loop invariants
39
define(wtxt, %l0)
40
define(tmp, %l1)
41
define(diff, %l2)
42
define(nrounds, %l3)
43
44

! Loop variables
45
define(round, %l4)
46
define(i, %l5)
47
define(key, %o4)
48

49
50
51
! Further loop invariants
define(T0, %l6)
define(T1, %l7)
52
define(T2, %g5)
53
define(T3, %o7)
54
55

C IDX1 cointains the permutation values * 4 + 2
56
define(IDX1, <T + AES_SIDX1 >)
57
C IDX3 cointains the permutation values * 4
58
define(IDX3, <T + AES_SIDX3 >)
59

60
! Teporaries
61
define(t0, %o0)
62
define(t1, %o1)
63
define(t2, %o2)
64
65
define(t3, %o3)

Niels Möller's avatar
Niels Möller committed
66
67
68
69
70
71
72
73
74
C AES_ROUND(i)
C Compute one word in the round function. 
C Input in wtxt, output stored in tmp + i.
C
C The comments mark which j in T->table[j][ Bj(wtxt[IDXi(i)]) ]
C the instruction is a part of. 
C
C The code uses the register %o[j], aka tj, as the primary 
C register for that sub-expression. True for j==1,3.
75
76
define(<AES_ROUND>, <
	ld	[IDX1+$1], t1		! 1
77
	ldub	[wtxt+$1+3], t0		! 0
78
	ldub	[wtxt+t1], t1		! 1
79
	sll	t0, 2, t0		! 0
80
	
81
	ld	[T0+t0], t0		! 0
82
	sll	t1, 2, t1		! 1
83
84
85
86
	ld	[T1+t1], t1		! 1
	ld	[IDX3+$1], t3		! 3
	
	xor	t0, t1, t0		! 0, 1
87
	! IDX2(j) = j XOR 2
88
	ldub	[wtxt+eval($1 ^ 8)+1], t2	! 2
89
90
	ldub	[wtxt+t3], t3		! 3
	sll	t2, 2, t2		! 2
91
	
92
93
94
95
	ld	[T2+t2], t2		! 2
	sll	t3, 2, t3		! 3
	ld	[T3+t3], t3		! 3
	xor	t0, t2, t0		! 0, 1, 2
96
	
97
98
99
100
	! Fetch roundkey
	ld	[key + $1], t1
	xor	t0, t3, t0		! 0, 1, 2, 3
	xor	t0, t1, t0
101
	st	t0, [tmp + $1]>)dnl
Niels Möller's avatar
Niels Möller committed
102
103
104

C AES_FINAL_ROUND(i)
C Compute one word in the final round function. 
105
C Input in wtxt, output converted to an octet string and stored at dst. 
Niels Möller's avatar
Niels Möller committed
106
107
108
109
110
111
112
113
114
115
116
117
C
C The comments mark which j in T->table[j][ Bj(wtxt[IDXi(i)]) ]
C the instruction is a part of. 
define(<AES_FINAL_ROUND>, <
	ld	[IDX1+$1], t1		! 1
	ldub	[wtxt+t1], t1		! 1

	ld	[wtxt+$1], t0		! 0
	! IDX2(j) = j XOR 2
	lduh	[wtxt+eval($1 ^ 8)], t2	! 2
	and	t0, 255, t0		! 0
	ld	[IDX3 + $1], t3		! 3
118
	
Niels Möller's avatar
Niels Möller committed
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
	and	t2, 255, t2		! 2
	ldub	[T+t1], t1		! 1
	ldub	[T+t0], t0		! 0
	sll	t1, 8, t1		! 1
	
	ldub	[wtxt+t3], t3		! 3
	or	t0, t1, t0		! 0, 1
	ldub	[T+t2], t2		! 2
	ldub	[T+t3], t3		! 3
	
	sll	t2, 16, t2		! 2
	or	t0, t2, t0		! 0, 1, 2
	ld	[key + $1], t2
	sll	t3, 24, t3		! 3
	
	or	t0, t3, t0		! 0, 1, 2, 3
	xor	t0, t2, t0
	
	srl	t0, 24, t3
	srl	t0, 16, t2
	srl	t0, 8, t1
140
	stb	t1, [dst+$1+1]
Niels Möller's avatar
Niels Möller committed
141
	
142
143
144
	stb	t3, [dst+$1+3]
	stb	t2, [dst+$1+2]
	stb	t0, [dst+$1]>)dnl
145
	
146
147
148
149
150
151
152
153
C The stack frame looks like
C
C %fp -   4: OS-dependent link field
C %fp -   8: OS-dependent link field
C %fp -  24: tmp, uint32_t[4]
C %fp -  40: wtxt, uint32_t[4]
C %fp - 136: OS register save area. 
define(<FRAME_SIZE>, 136)
154

155
156
157
158
159
160
	.section	".text"
	.align 16
	.global _aes_crypt
	.type	_aes_crypt,#function
	.proc	020
	
161
_aes_crypt:
162
	save	%sp, -FRAME_SIZE, %sp
163
	cmp	length, 0
164
	be	.Lend
165
166
167
168
	! wtxt
	add	%fp, -24, wtxt
	
	add	%fp, -40, tmp
169

170
	ld	[ctx + AES_NROUNDS], nrounds
171
172
	! Compute xor, so that we can swap efficiently.
	xor	wtxt, tmp, diff
173
	! The loop variable will be multiplied by 16.
174
175
	! More loop invariants
	add	T, AES_TABLE0, T0
Niels Möller's avatar
Niels Möller committed
176
	
177
	add	T, AES_TABLE1, T1
178
179
	add	T, AES_TABLE2, T2
	add	T, AES_TABLE3, T3
Niels Möller's avatar
Niels Möller committed
180
	
181
	! Read src, and add initial subkey
182
	! Difference between ctx and src.
Niels Möller's avatar
Niels Möller committed
183
	! NOTE: These instructions are duplicated in the delay slot,
184
	! and the instruction before the branch.
185
186
187
	sub	ctx, src, %g2
	! Difference between wtxt and src
	sub	wtxt, src, %g3
188
.Lblock_loop:
189
190
	! For stop condition. Note that src is incremented in the
	! delay slot
191
	add	src, 8, %g1
192
	
193
.Lsource_loop:
194
195
196
197
	ldub	[src+3], t3
	ldub	[src+2], t2
	sll	t3, 24, t3
	ldub	[src+1], t1
198
	
199
200
201
202
	sll	t2, 16, t2
	or	t3, t2, t3
	ldub	[src], t0
	sll	t1, 8, t1
203
	
204
	! Get subkey
205
	ld	[src+%g2], t2
206
207
	or	t3, t1, t3
	or	t3, t0, t3
208
	xor	t3, t2, t3
209
	
210
	cmp	src, %g1
211
	st	t3, [src+%g3]
212
	bleu	.Lsource_loop
213
	add	src, 4, src
214
	
215
	sub	nrounds, 1, round
216
	add	ctx, 16, key
Niels Möller's avatar
Niels Möller committed
217

218
.Lround_loop:
219

Niels Möller's avatar
Niels Möller committed
220
221
222
223
	AES_ROUND(0)	! i = 0
	AES_ROUND(4)	! i = 1
	AES_ROUND(8)	! i = 2
	AES_ROUND(12)	! i = 3
224
			
225
	! switch roles for tmp and wtxt
226
	xor	wtxt, diff, wtxt
227
	xor	tmp, diff, tmp
228

229
	subcc	round, 1, round
230
	bne	.Lround_loop
Niels Möller's avatar
Niels Möller committed
231
	add	key, 16, key
232

233
	C Final round, and storage of the output
234

Niels Möller's avatar
Niels Möller committed
235
	AES_FINAL_ROUND(0)	! i = 0
Niels Möller's avatar
Niels Möller committed
236
237
238
	AES_FINAL_ROUND(4)	! i = 1
	AES_FINAL_ROUND(8)	! i = 2
	AES_FINAL_ROUND(12)	! i = 3
239
240
	add	dst, 16, dst
		
241
	addcc	length, -16, length
242
	sub	ctx, src, %g2
243
	
244
	bne	.Lblock_loop
245
	sub	wtxt, src, %g3
246

247
.Lend:
248
249
	ret
	restore
250
251
252
253
.LLFE1:
.LLfe1:
	.size	_aes_crypt,.LLfe1-_aes_crypt

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
	! Benchmarks on my slow sparcstation:	
	! Original C code	
	! aes128 (ECB encrypt): 14.36s, 0.696MB/s
	! aes128 (ECB decrypt): 17.19s, 0.582MB/s
	! aes128 (CBC encrypt): 16.08s, 0.622MB/s
	! aes128 ((CBC decrypt)): 18.79s, 0.532MB/s
	! 
	! aes192 (ECB encrypt): 16.85s, 0.593MB/s
	! aes192 (ECB decrypt): 19.64s, 0.509MB/s
	! aes192 (CBC encrypt): 18.43s, 0.543MB/s
	! aes192 (CBC decrypt): 20.76s, 0.482MB/s
	! 
	! aes256 (ECB encrypt): 19.12s, 0.523MB/s
	! aes256 (ECB decrypt): 22.57s, 0.443MB/s
	! aes256 (CBC encrypt): 20.92s, 0.478MB/s
	! aes256 (CBC decrypt): 23.22s, 0.431MB/s

	! After unrolling key_addition32, and getting rid of
	! some sll x, 2, x, encryption speed is 0.760 MB/s.

	! Next, the C code was optimized to use larger tables and
	! no rotates. New timings:
	! aes128 (ECB encrypt): 13.10s, 0.763MB/s
	! aes128 (ECB decrypt): 11.51s, 0.869MB/s
	! aes128 (CBC encrypt): 15.15s, 0.660MB/s
	! aes128 (CBC decrypt): 13.10s, 0.763MB/s
	! 
	! aes192 (ECB encrypt): 15.68s, 0.638MB/s
	! aes192 (ECB decrypt): 13.59s, 0.736MB/s
	! aes192 (CBC encrypt): 17.65s, 0.567MB/s
	! aes192 (CBC decrypt): 15.31s, 0.653MB/s
	! 
	! aes256 (ECB encrypt): 17.95s, 0.557MB/s
	! aes256 (ECB decrypt): 15.90s, 0.629MB/s
	! aes256 (CBC encrypt): 20.16s, 0.496MB/s
	! aes256 (CBC decrypt): 17.47s, 0.572MB/s

	! After optimization using pre-shifted indices
	! (AES_SIDX[1-3]): 
	! aes128 (ECB encrypt): 12.46s, 0.803MB/s
	! aes128 (ECB decrypt): 10.74s, 0.931MB/s
	! aes128 (CBC encrypt): 17.74s, 0.564MB/s
	! aes128 (CBC decrypt): 12.43s, 0.805MB/s
	! 
	! aes192 (ECB encrypt): 14.59s, 0.685MB/s
	! aes192 (ECB decrypt): 12.76s, 0.784MB/s
	! aes192 (CBC encrypt): 19.97s, 0.501MB/s
	! aes192 (CBC decrypt): 14.46s, 0.692MB/s
	! 
	! aes256 (ECB encrypt): 17.00s, 0.588MB/s
	! aes256 (ECB decrypt): 14.81s, 0.675MB/s
	! aes256 (CBC encrypt): 22.65s, 0.442MB/s
	! aes256 (CBC decrypt): 16.46s, 0.608MB/s
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

	! After implementing double buffering
	! aes128 (ECB encrypt): 12.59s, 0.794MB/s
	! aes128 (ECB decrypt): 10.56s, 0.947MB/s
	! aes128 (CBC encrypt): 17.91s, 0.558MB/s
	! aes128 (CBC decrypt): 12.30s, 0.813MB/s
	! 
	! aes192 (ECB encrypt): 15.03s, 0.665MB/s
	! aes192 (ECB decrypt): 12.56s, 0.796MB/s
	! aes192 (CBC encrypt): 20.30s, 0.493MB/s
	! aes192 (CBC decrypt): 14.26s, 0.701MB/s
	! 
	! aes256 (ECB encrypt): 17.30s, 0.578MB/s
	! aes256 (ECB decrypt): 14.51s, 0.689MB/s
	! aes256 (CBC encrypt): 22.75s, 0.440MB/s
	! aes256 (CBC decrypt): 16.35s, 0.612MB/s
	
	! After reordering aes-encrypt.c and aes-decypt.c
	! (the order probably causes strange cache-effects):
	! aes128 (ECB encrypt): 9.21s, 1.086MB/s
	! aes128 (ECB decrypt): 11.13s, 0.898MB/s
	! aes128 (CBC encrypt): 14.12s, 0.708MB/s
	! aes128 (CBC decrypt): 13.77s, 0.726MB/s
	! 
	! aes192 (ECB encrypt): 10.86s, 0.921MB/s
	! aes192 (ECB decrypt): 13.17s, 0.759MB/s
	! aes192 (CBC encrypt): 15.74s, 0.635MB/s
	! aes192 (CBC decrypt): 15.91s, 0.629MB/s
	! 
	! aes256 (ECB encrypt): 12.71s, 0.787MB/s
	! aes256 (ECB decrypt): 15.38s, 0.650MB/s
	! aes256 (CBC encrypt): 17.49s, 0.572MB/s
	! aes256 (CBC decrypt): 17.87s, 0.560MB/s
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357

	! After further optimizations of the initial and final loops,
	! source_loop and final_loop. 
	! aes128 (ECB encrypt): 8.07s, 1.239MB/s
	! aes128 (ECB decrypt): 9.48s, 1.055MB/s
	! aes128 (CBC encrypt): 12.76s, 0.784MB/s
	! aes128 (CBC decrypt): 12.15s, 0.823MB/s
	! 
	! aes192 (ECB encrypt): 9.43s, 1.060MB/s
	! aes192 (ECB decrypt): 11.20s, 0.893MB/s
	! aes192 (CBC encrypt): 14.19s, 0.705MB/s
	! aes192 (CBC decrypt): 13.97s, 0.716MB/s
	! 
	! aes256 (ECB encrypt): 10.81s, 0.925MB/s
	! aes256 (ECB decrypt): 12.92s, 0.774MB/s
	! aes256 (CBC encrypt): 15.59s, 0.641MB/s
	! aes256 (CBC decrypt): 15.76s, 0.635MB/s