aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86/crypto/twofish-i586-asm_32.S
blob: 658af4bb35c9ff852033d0f4858824e92d4f623b (plain) (blame)
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
/***************************************************************************
*   Copyright (C) 2006 by Joachim Fritschi, <jfritschi@freenet.de>        *
*                                                                         *
*   This program is free software; you can redistribute it and/or modify  *
*   it under the terms of the GNU General Public License as published by  *
*   the Free Software Foundation; either version 2 of the License, or     *
*   (at your option) any later version.                                   *
*                                                                         *
*   This program 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 General Public License for more details.                          *
*                                                                         *
*   You should have received a copy of the GNU General Public License     *
*   along with this program; if not, write to the                         *
*   Free Software Foundation, Inc.,                                       *
*   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
***************************************************************************/

.file "twofish-i586-asm.S"
.text

#include <asm/asm-offsets.h>

/* return address at 0 */

#define in_blk    12  /* input byte array address parameter*/
#define out_blk   8  /* output byte array address parameter*/
#define ctx       4  /* Twofish context structure */

#define a_offset	0
#define b_offset	4
#define c_offset	8
#define d_offset	12

/* Structure of the crypto context struct*/

#define s0	0	/* S0 Array 256 Words each */
#define s1	1024	/* S1 Array */
#define s2	2048	/* S2 Array */
#define s3	3072	/* S3 Array */
#define w	4096	/* 8 whitening keys (word) */
#define k	4128	/* key 1-32 ( word ) */

/* define a few register aliases to allow macro substitution */

#define R0D    %eax
#define R0B    %al
#define R0H    %ah

#define R1D    %ebx
#define R1B    %bl
#define R1H    %bh

#define R2D    %ecx
#define R2B    %cl
#define R2H    %ch

#define R3D    %edx
#define R3B    %dl
#define R3H    %dh


/* performs input whitening */
#define input_whitening(src,context,offset)\
	xor	w+offset(context),	src;

/* performs input whitening */
#define output_whitening(src,context,offset)\
	xor	w+16+offset(context),	src;

/*
 * a input register containing a (rotated 16)
 * b input register containing b
 * c input register containing c
 * d input register containing d (already rol $1)
 * operations on a and b are interleaved to increase performance
 */
#define encrypt_round(a,b,c,d,round)\
	push	d ## D;\
	movzx	b ## B,		%edi;\
	mov	s1(%ebp,%edi,4),d ## D;\
	movzx	a ## B,		%edi;\
	mov	s2(%ebp,%edi,4),%esi;\
	movzx	b ## H,		%edi;\
	ror	$16,		b ## D;\
	xor	s2(%ebp,%edi,4),d ## D;\
	movzx	a ## H,		%edi;\
	ror	$16,		a ## D;\
	xor	s3(%ebp,%edi,4),%esi;\
	movzx	b ## B,		%edi;\
	xor	s3(%ebp,%edi,4),d ## D;\
	movzx	a ## B,		%edi;\
	xor	(%ebp,%edi,4),	%esi;\
	movzx	b ## H,		%edi;\
	ror	$15,		b ## D;\
	xor	(%ebp,%edi,4),	d ## D;\
	movzx	a ## H,		%edi;\
	xor	s1(%ebp,%edi,4),%esi;\
	pop	%edi;\
	add	d ## D,		%esi;\
	add	%esi,		d ## D;\
	add	k+round(%ebp),	%esi;\
	xor	%esi,		c ## D;\
	rol	$15,		c ## D;\
	add	k+4+round(%ebp),d ## D;\
	xor	%edi,		d ## D;

/*
 * a input register containing a (rotated 16)
 * b input register containing b
 * c input register containing c
 * d input register containing d (already rol $1)
 * operations on a and b are interleaved to increase performance
 * last round has different rotations for the output preparation
 */
#define encrypt_last_round(a,b,c,d,round)\
	push	d ## D;\
	movzx	b ## B,		%edi;\
	mov	s1(%ebp,%edi,4),d ## D;\
	movzx	a ## B,		%edi;\
	mov	s2(%ebp,%edi,4),%esi;\
	movzx	b ## H,		%edi;\
	ror	$16,		b ## D;\
	xor	s2(%ebp,%edi,4),d ## D;\
	movzx	a ## H,		%edi;\
	ror	$16,		a ## D;\
	xor	s3(%ebp,%edi,4),%esi;\
	movzx	b ## B,		%edi;\
	xor	s3(%ebp,%edi,4),d ## D;\
	movzx	a ## B,		%edi;\
	xor	(%ebp,%edi,4),	%esi;\
	movzx	b ## H,		%edi;\
	ror	$16,		b ## D;\
	xor	(%ebp,%edi,4),	d ## D;\
	movzx	a ## H,		%edi;\
	xor	s1(%ebp,%edi,4),%esi;\
	pop	%edi;\
	add	d ## D,		%esi;\
	add	%esi,		d ## D;\
	add	k+round(%ebp),	%esi;\
	xor	%esi,		c ## D;\
	ror	$1,		c ## D;\
	add	k+4+round(%ebp),d ## D;\
	xor	%edi,		d ## D;

/*
 * a input register containing a
 * b input register containing b (rotated 16)
 * c input register containing c
 * d input register containing d (already rol $1)
 * operations on a and b are interleaved to increase performance
 */
#define decrypt_round(a,b,c,d,round)\
	push	c ## D;\
	movzx	a ## B,		%edi;\
	mov	(%ebp,%edi,4),	c ## D;\
	movzx	b ## B,		%edi;\
	mov	s3(%ebp,%edi,4),%esi;\
	movzx	a ## H,		%edi;\
	ror	$16,		a ## D;\
	xor	s1(%ebp,%edi,4),c ## D;\
	movzx	b ## H,		%edi;\
	ror	$16,		b ## D;\
	xor	(%ebp,%edi,4),	%esi;\
	movzx	a ## B,		%edi;\
	xor	s2(%ebp,%edi,4),c ## D;\
	movzx	b ## B,		%edi;\
	xor	s1(%ebp,%edi,4),%esi;\
	movzx	a ## H,		%edi;\
	ror	$15,		a ## D;\
	xor	s3(%ebp,%edi,4),c ## D;\
	movzx	b ## H,		%edi;\
	xor	s2(%ebp,%edi,4),%esi;\
	pop	%edi;\
	add	%esi,		c ## D;\
	add	c ## D,		%esi;\
	add	k+round(%ebp),	c ## D;\
	xor	%edi,		c ## D;\
	add	k+4+round(%ebp),%esi;\
	xor	%esi,		d ## D;\
	rol	$15,		d ## D;

/*
 * a input register containing a
 * b input register containing b (rotated 16)
 * c input register containing c
 * d input register containing d (already rol $1)
 * operations on a and b are interleaved to increase performance
 * last round has different rotations for the output preparation
 */
#define decrypt_last_round(a,b,c,d,round)\
	push	c ## D;\
	movzx	a ## B,		%edi;\
	mov	(%ebp,%edi,4),	c ## D;\
	movzx	b ## B,		%edi;\
	mov	s3(%ebp,%edi,4),%esi;\
	movzx	a ## H,		%edi;\
	ror	$16,		a ## D;\
	xor	s1(%ebp,%edi,4),c ## D;\
	movzx	b ## H,		%edi;\
	ror	$16,		b ## D;\
	xor	(%ebp,%edi,4),	%esi;\
	movzx	a ## B,		%edi;\
	xor	s2(%ebp,%edi,4),c ## D;\
	movzx	b ## B,		%edi;\
	xor	s1(%ebp,%edi,4),%esi;\
	movzx	a ## H,		%edi;\
	ror	$16,		a ## D;\
	xor	s3(%ebp,%edi,4),c ## D;\
	movzx	b ## H,		%edi;\
	xor	s2(%ebp,%edi,4),%esi;\
	pop	%edi;\
	add	%esi,		c ## D;\
	add	c ## D,		%esi;\
	add	k+round(%ebp),	c ## D;\
	xor	%edi,		c ## D;\
	add	k+4+round(%ebp),%esi;\
	xor	%esi,		d ## D;\
	ror	$1,		d ## D;

.align 4
.global twofish_enc_blk
.global twofish_dec_blk

twofish_enc_blk:
	push	%ebp			/* save registers according to calling convention*/
	push    %ebx
	push    %esi
	push    %edi

	mov	ctx + 16(%esp),	%ebp	/* abuse the base pointer: set new base
					 * pointer to the ctx address */
	mov     in_blk+16(%esp),%edi	/* input address in edi */

	mov	(%edi),		%eax
	mov	b_offset(%edi),	%ebx
	mov	c_offset(%edi),	%ecx
	mov	d_offset(%edi),	%edx
	input_whitening(%eax,%ebp,a_offset)
	ror	$16,	%eax
	input_whitening(%ebx,%ebp,b_offset)
	input_whitening(%ecx,%ebp,c_offset)
	input_whitening(%edx,%ebp,d_offset)
	rol	$1,	%edx

	encrypt_round(R0,R1,R2,R3,0);
	encrypt_round(R2,R3,R0,R1,8);
	encrypt_round(R0,R1,R2,R3,2*8);
	encrypt_round(R2,R3,R0,R1,3*8);
	encrypt_round(R0,R1,R2,R3,4*8);
	encrypt_round(R2,R3,R0,R1,5*8);
	encrypt_round(R0,R1,R2,R3,6*8);
	encrypt_round(R2,R3,R0,R1,7*8);
	encrypt_round(R0,R1,R2,R3,8*8);
	encrypt_round(R2,R3,R0,R1,9*8);
	encrypt_round(R0,R1,R2,R3,10*8);
	encrypt_round(R2,R3,R0,R1,11*8);
	encrypt_round(R0,R1,R2,R3,12*8);
	encrypt_round(R2,R3,R0,R1,13*8);
	encrypt_round(R0,R1,R2,R3,14*8);
	encrypt_last_round(R2,R3,R0,R1,15*8);

	output_whitening(%eax,%ebp,c_offset)
	output_whitening(%ebx,%ebp,d_offset)
	output_whitening(%ecx,%ebp,a_offset)
	output_whitening(%edx,%ebp,b_offset)
	mov	out_blk+16(%esp),%edi;
	mov	%eax,		c_offset(%edi)
	mov	%ebx,		d_offset(%edi)
	mov	%ecx,		(%edi)
	mov	%edx,		b_offset(%edi)

	pop	%edi
	pop	%esi
	pop	%ebx
	pop	%ebp
	mov	$1,	%eax
	ret

twofish_dec_blk:
	push	%ebp			/* save registers according to calling convention*/
	push    %ebx
	push    %esi
	push    %edi


	mov	ctx + 16(%esp),	%ebp	/* abuse the base pointer: set new base
					 * pointer to the ctx address */
	mov     in_blk+16(%esp),%edi	/* input address in edi */

	mov	(%edi),		%eax
	mov	b_offset(%edi),	%ebx
	mov	c_offset(%edi),	%ecx
	mov	d_offset(%edi),	%edx
	output_whitening(%eax,%ebp,a_offset)
	output_whitening(%ebx,%ebp,b_offset)
	ror	$16,	%ebx
	output_whitening(%ecx,%ebp,c_offset)
	output_whitening(%edx,%ebp,d_offset)
	rol	$1,	%ecx

	decrypt_round(R0,R1,R2,R3,15*8);
	decrypt_round(R2,R3,R0,R1,14*8);
	decrypt_round(R0,R1,R2,R3,13*8);
	decrypt_round(R2,R3,R0,R1,12*8);
	decrypt_round(R0,R1,R2,R3,11*8);
	decrypt_round(R2,R3,R0,R1,10*8);
	decrypt_round(R0,R1,R2,R3,9*8);
	decrypt_round(R2,R3,R0,R1,8*8);
	decrypt_round(R0,R1,R2,R3,7*8);
	decrypt_round(R2,R3,R0,R1,6*8);
	decrypt_round(R0,R1,R2,R3,5*8);
	decrypt_round(R2,R3,R0,R1,4*8);
	decrypt_round(R0,R1,R2,R3,3*8);
	decrypt_round(R2,R3,R0,R1,2*8);
	decrypt_round(R0,R1,R2,R3,1*8);
	decrypt_last_round(R2,R3,R0,R1,0);

	input_whitening(%eax,%ebp,c_offset)
	input_whitening(%ebx,%ebp,d_offset)
	input_whitening(%ecx,%ebp,a_offset)
	input_whitening(%edx,%ebp,b_offset)
	mov	out_blk+16(%esp),%edi;
	mov	%eax,		c_offset(%edi)
	mov	%ebx,		d_offset(%edi)
	mov	%ecx,		(%edi)
	mov	%edx,		b_offset(%edi)

	pop	%edi
	pop	%esi
	pop	%ebx
	pop	%ebp
	mov	$1,	%eax
	ret