/***************************************************************************
* 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 <linux/linkage.h>
#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;
ENTRY(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
ENDPROC(twofish_enc_blk)
ENTRY(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
ENDPROC(twofish_dec_blk)