#! /usr/bin/env perl
# Copyright 2014-2020 The OpenSSL Project Authors. All Rights Reserved.
#
# Licensed under the OpenSSL license (the "License"). You may not use
# this file except in compliance with the License. You can obtain a copy
# in the file LICENSE in the source distribution or at
# https://www.openssl.org/source/license.html
#
# ====================================================================
# Written by Andy Polyakov <appro@openssl.org> for the OpenSSL
# project. The module is, however, dual licensed under OpenSSL and
# CRYPTOGAMS licenses depending on where you obtain it. For further
# details see http://www.openssl.org/~appro/cryptogams/.
# ====================================================================
#
# RC4 for C64x+.
#
# April 2014
#
# RC4 subroutine processes one byte in 7.0 cycles, which is 3x faster
# than TI CGT-generated code. Loop is scheduled in such way that
# there is only one reference to memory in each cycle. This is done
# to avoid L1D memory banking conflicts, see SPRU871 TI publication
# for further details. Otherwise it should be possible to schedule
# the loop for iteration interval of 6...
($KEY,$LEN,$INP,$OUT)=("A4","B4","A6","B6");
($KEYA,$XX,$TY,$xx,$ONE,$ret)=map("A$_",(5,7,8,9,1,2));
($KEYB,$YY,$TX,$tx,$SUM,$dat)=map("B$_",(5,7,8,9,1,2));
$code.=<<___;
.text
.if .ASSEMBLER_VERSION<7000000
.asg 0,__TI_EABI__
.endif
.if __TI_EABI__
.nocmp
.asg RC4,_RC4
.asg RC4_set_key,_RC4_set_key
.asg RC4_options,_RC4_options
.endif
.global _RC4
.align 16
_RC4:
.asmfunc
MV $LEN,B0
[!B0] BNOP B3 ; if (len==0) return;
||[B0] ADD $KEY,2,$KEYA
||[B0] ADD $KEY,2,$KEYB
[B0] MVK 1,$ONE
||[B0] LDBU *${KEYA}[-2],$XX ; key->x
[B0] LDBU *${KEYB}[-1],$YY ; key->y
|| NOP 4
ADD4 $ONE,$XX,$XX
LDBU *${KEYA}[$XX],$TX
|| MVC $LEN,ILC
NOP 4
;;==================================================
SPLOOP 7
|| ADD4 $TX,$YY,$YY
LDBU *${KEYB}[$YY],$TY
|| MVD $XX,$xx
|| ADD4 $ONE,$XX,$XX
LDBU *${KEYA}[$XX],$tx
CMPEQ $YY,$XX,B0
|| NOP 3
STB $TX,*${KEYB}[$YY]
||[B0] ADD4 $TX,$YY,$YY
STB $TY,*${KEYA}[$xx]
||[!B0] ADD4 $tx,$YY,$YY
||[!B0] MVD $tx,$TX
ADD4 $TY,$TX,$SUM ; [0,0] $TX is not replaced by $tx yet!
|| NOP 2
LDBU *$INP++,$dat
|| NOP 2
LDBU *${KEYB}[$SUM],$ret
|| NOP 5
XOR.L $dat,$ret,$ret
SPKERNEL
|| STB $ret,*$OUT++
;;==================================================
SUB4 $XX,$ONE,$XX
|| NOP 5
STB $XX,*${KEYA}[-2] ; key->x
|| SUB4 $YY,$TX,$YY
|| BNOP B3
STB $YY,*${KEYB}[-1] ; key->y
|| NOP 5
.endasmfunc
.global _RC4_set_key
.align 16
_RC4_set_key:
.asmfunc
.if .BIG_ENDIAN
MVK 0x00000404,$ONE
|| MVK 0x00000203,B0
MVKH 0x04040000,$ONE
|| MVKH 0x00010000,B0
.else
MVK 0x00000404,$ONE
|| MVK 0x00000100,B0
MVKH 0x04040000,$ONE
|| MVKH 0x03020000,B0
.endif
ADD $KEY,2,$KEYA
|| ADD $KEY,2,$KEYB
|| ADD $INP,$LEN,$ret ; end of input
LDBU *${INP}++,$dat
|| MVK 0,$TX
STH $TX,*${KEY}++ ; key->x=key->y=0
|| MV B0,A0
|| MVK 64-4,B0
;;==================================================
SPLOOPD 1
|| MVC B0,ILC
STNW A0,*${KEY}++
|| ADD4 $ONE,A0,A0
SPKERNEL
;;==================================================
MVK 0,$YY
|| MVK 0,$XX
MVK 1,$ONE
|| MVK 256-1,B0
;;==================================================
SPLOOPD 8
|| MVC B0,ILC
ADD4 $dat,$YY,$YY
|| CMPEQ $INP,$ret,A0 ; end of input?
LDBU *${KEYB}[$YY],$TY
|| MVD $XX,$xx
|| ADD4 $ONE,$XX,$XX
LDBU *${KEYA}[$XX],$tx
||[A0] SUB $INP,$LEN,$INP ; rewind
LDBU *${INP}++,$dat
|| CMPEQ $YY,$XX,B0
|| NOP 3
STB $TX,*${KEYB}[$YY]
||[B0] ADD4 $TX,$YY,$YY
STB $TY,*${KEYA}[$xx]
||[!B0] ADD4 $tx,$YY,$YY
||[!B0] MV $tx,$TX
SPKERNEL
;;==================================================
BNOP B3,5
.endasmfunc
.global _RC4_options
.align 16
_RC4_options:
_rc4_options:
.asmfunc
BNOP B3,1
ADDKPC _rc4_options,B4
.if __TI_EABI__
MVKL \$PCR_OFFSET(rc4_options,_rc4_options),A4
MVKH \$PCR_OFFSET(rc4_options,_rc4_options),A4
.else
MVKL (rc4_options-_rc4_options),A4
MVKH (rc4_options-_rc4_options),A4
.endif
ADD B4,A4,A4
.endasmfunc
.if __TI_EABI__
.sect ".text:rc4_options.const"
.else
.sect ".const:rc4_options"
.endif
.align 4
rc4_options:
.cstring "rc4(sploop,char)"
.cstring "RC4 for C64+, CRYPTOGAMS by <appro\@openssl.org>"
.align 4
___
$output=pop;
open STDOUT,">$output";
print $code;
close STDOUT or die "error closing STDOUT: $!";
