openssl/crypto/aes/asm/aes-riscv32-zkn.pl

1090 lines
28 KiB
Perl

#! /usr/bin/env perl
# This file is dual-licensed, meaning that you can use it under your
# choice of either of the following two licenses:
#
# Copyright 2022-2023 The OpenSSL Project Authors. All Rights Reserved.
#
# Licensed under the Apache License 2.0 (the "License"). You can obtain
# a copy in the file LICENSE in the source distribution or at
# https://www.openssl.org/source/license.html
#
# or
#
# Copyright (c) 2022, Hongren (Zenithal) Zheng <i@zenithal.me>
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
# $output is the last argument if it looks like a file (it has an extension)
# $flavour is the first argument if it doesn't look like a file
$output = $#ARGV >= 0 && $ARGV[$#ARGV] =~ m|\.\w+$| ? pop : undef;
$flavour = $#ARGV >= 0 && $ARGV[0] !~ m|\.| ? shift : undef;
$output and open STDOUT,">$output";
################################################################################
# Utility functions to help with keeping track of which registers to stack/
# unstack when entering / exiting routines.
################################################################################
{
# Callee-saved registers
my @callee_saved = map("x$_",(2,8,9,18..27));
# Caller-saved registers
my @caller_saved = map("x$_",(1,5..7,10..17,28..31));
my @must_save;
sub use_reg {
my $reg = shift;
if (grep(/^$reg$/, @callee_saved)) {
push(@must_save, $reg);
} elsif (!grep(/^$reg$/, @caller_saved)) {
# Register is not usable!
die("Unusable register ".$reg);
}
return $reg;
}
sub use_regs {
return map(use_reg("x$_"), @_);
}
sub save_regs {
my $ret = '';
my $stack_reservation = ($#must_save + 1) * 8;
my $stack_offset = $stack_reservation;
if ($stack_reservation % 16) {
$stack_reservation += 8;
}
$ret.=" addi sp,sp,-$stack_reservation\n";
foreach (@must_save) {
$stack_offset -= 8;
$ret.=" sw $_,$stack_offset(sp)\n";
}
return $ret;
}
sub load_regs {
my $ret = '';
my $stack_reservation = ($#must_save + 1) * 8;
my $stack_offset = $stack_reservation;
if ($stack_reservation % 16) {
$stack_reservation += 8;
}
foreach (@must_save) {
$stack_offset -= 8;
$ret.=" lw $_,$stack_offset(sp)\n";
}
$ret.=" addi sp,sp,$stack_reservation\n";
return $ret;
}
sub clear_regs {
@must_save = ();
}
}
################################################################################
# util for encoding scalar crypto extension instructions
################################################################################
my @regs = map("x$_",(0..31));
my %reglookup;
@reglookup{@regs} = @regs;
# Takes a register name, possibly an alias, and converts it to a register index
# from 0 to 31
sub read_reg {
my $reg = lc shift;
if (!exists($reglookup{$reg})) {
die("Unknown register ".$reg);
}
my $regstr = $reglookup{$reg};
if (!($regstr =~ /^x([0-9]+)$/)) {
die("Could not process register ".$reg);
}
return $1;
}
sub aes32dsi {
# Encoding for aes32dsi rd, rs1, rs2, bs instruction on RV32
# bs_XXXXX_ rs2 _ rs1 _XXX_ rd _XXXXXXX
my $template = 0b00_10101_00000_00000_000_00000_0110011;
my $rd = read_reg shift;
my $rs1 = read_reg shift;
my $rs2 = read_reg shift;
my $bs = shift;
return ".word ".($template | ($bs << 30) | ($rs2 << 20) | ($rs1 << 15) | ($rd << 7));
}
sub aes32dsmi {
# Encoding for aes32dsmi rd, rs1, rs2, bs instruction on RV32
# bs_XXXXX_ rs2 _ rs1 _XXX_ rd _XXXXXXX
my $template = 0b00_10111_00000_00000_000_00000_0110011;
my $rd = read_reg shift;
my $rs1 = read_reg shift;
my $rs2 = read_reg shift;
my $bs = shift;
return ".word ".($template | ($bs << 30) | ($rs2 << 20) | ($rs1 << 15) | ($rd << 7));
}
sub aes32esi {
# Encoding for aes32esi rd, rs1, rs2, bs instruction on RV32
# bs_XXXXX_ rs2 _ rs1 _XXX_ rd _XXXXXXX
my $template = 0b00_10001_00000_00000_000_00000_0110011;
my $rd = read_reg shift;
my $rs1 = read_reg shift;
my $rs2 = read_reg shift;
my $bs = shift;
return ".word ".($template | ($bs << 30) | ($rs2 << 20) | ($rs1 << 15) | ($rd << 7));
}
sub aes32esmi {
# Encoding for aes32esmi rd, rs1, rs2, bs instruction on RV32
# bs_XXXXX_ rs2 _ rs1 _XXX_ rd _XXXXXXX
my $template = 0b00_10011_00000_00000_000_00000_0110011;
my $rd = read_reg shift;
my $rs1 = read_reg shift;
my $rs2 = read_reg shift;
my $bs = shift;
return ".word ".($template | ($bs << 30) | ($rs2 << 20) | ($rs1 << 15) | ($rd << 7));
}
sub rori {
# Encoding for ror rd, rs1, imm instruction on RV64
# XXXXXXX_shamt_ rs1 _XXX_ rd _XXXXXXX
my $template = 0b0110000_00000_00000_101_00000_0010011;
my $rd = read_reg shift;
my $rs1 = read_reg shift;
my $shamt = shift;
return ".word ".($template | ($shamt << 20) | ($rs1 << 15) | ($rd << 7));
}
################################################################################
# Register assignment for rv32i_zkne_encrypt and rv32i_zknd_decrypt
################################################################################
# Registers initially to hold AES state (called s0-s3 or y0-y3 elsewhere)
my ($Q0,$Q1,$Q2,$Q3) = use_regs(6..9);
# Function arguments (x10-x12 are a0-a2 in the ABI)
# Input block pointer, output block pointer, key pointer
my ($INP,$OUTP,$KEYP) = use_regs(10..12);
# Registers initially to hold Key
my ($T0,$T1,$T2,$T3) = use_regs(13..16);
# Loop counter
my ($loopcntr) = use_regs(30);
################################################################################
# Utility for rv32i_zkne_encrypt and rv32i_zknd_decrypt
################################################################################
# outer product of whole state into one column of key
sub outer {
my $inst = shift;
my $key = shift;
# state 0 to 3
my $s0 = shift;
my $s1 = shift;
my $s2 = shift;
my $s3 = shift;
my $ret = '';
$ret .= <<___;
@{[$inst->($key,$key,$s0,0)]}
@{[$inst->($key,$key,$s1,1)]}
@{[$inst->($key,$key,$s2,2)]}
@{[$inst->($key,$key,$s3,3)]}
___
return $ret;
}
sub aes32esmi4 {
return outer(\&aes32esmi, @_)
}
sub aes32esi4 {
return outer(\&aes32esi, @_)
}
sub aes32dsmi4 {
return outer(\&aes32dsmi, @_)
}
sub aes32dsi4 {
return outer(\&aes32dsi, @_)
}
################################################################################
# void rv32i_zkne_encrypt(const unsigned char *in, unsigned char *out,
# const AES_KEY *key);
################################################################################
my $code .= <<___;
.text
.balign 16
.globl rv32i_zkne_encrypt
.type rv32i_zkne_encrypt,\@function
rv32i_zkne_encrypt:
___
$code .= save_regs();
$code .= <<___;
# Load input to block cipher
lw $Q0,0($INP)
lw $Q1,4($INP)
lw $Q2,8($INP)
lw $Q3,12($INP)
# Load key
lw $T0,0($KEYP)
lw $T1,4($KEYP)
lw $T2,8($KEYP)
lw $T3,12($KEYP)
# Load number of rounds
lw $loopcntr,240($KEYP)
# initial transformation
xor $Q0,$Q0,$T0
xor $Q1,$Q1,$T1
xor $Q2,$Q2,$T2
xor $Q3,$Q3,$T3
# The main loop only executes the first N-2 rounds, each loop consumes two rounds
add $loopcntr,$loopcntr,-2
srli $loopcntr,$loopcntr,1
1:
# Grab next key in schedule
add $KEYP,$KEYP,16
lw $T0,0($KEYP)
lw $T1,4($KEYP)
lw $T2,8($KEYP)
lw $T3,12($KEYP)
@{[aes32esmi4 $T0,$Q0,$Q1,$Q2,$Q3]}
@{[aes32esmi4 $T1,$Q1,$Q2,$Q3,$Q0]}
@{[aes32esmi4 $T2,$Q2,$Q3,$Q0,$Q1]}
@{[aes32esmi4 $T3,$Q3,$Q0,$Q1,$Q2]}
# now T0~T3 hold the new state
# Grab next key in schedule
add $KEYP,$KEYP,16
lw $Q0,0($KEYP)
lw $Q1,4($KEYP)
lw $Q2,8($KEYP)
lw $Q3,12($KEYP)
@{[aes32esmi4 $Q0,$T0,$T1,$T2,$T3]}
@{[aes32esmi4 $Q1,$T1,$T2,$T3,$T0]}
@{[aes32esmi4 $Q2,$T2,$T3,$T0,$T1]}
@{[aes32esmi4 $Q3,$T3,$T0,$T1,$T2]}
# now Q0~Q3 hold the new state
add $loopcntr,$loopcntr,-1
bgtz $loopcntr,1b
# final two rounds
# Grab next key in schedule
add $KEYP,$KEYP,16
lw $T0,0($KEYP)
lw $T1,4($KEYP)
lw $T2,8($KEYP)
lw $T3,12($KEYP)
@{[aes32esmi4 $T0,$Q0,$Q1,$Q2,$Q3]}
@{[aes32esmi4 $T1,$Q1,$Q2,$Q3,$Q0]}
@{[aes32esmi4 $T2,$Q2,$Q3,$Q0,$Q1]}
@{[aes32esmi4 $T3,$Q3,$Q0,$Q1,$Q2]}
# now T0~T3 hold the new state
# Grab next key in schedule
add $KEYP,$KEYP,16
lw $Q0,0($KEYP)
lw $Q1,4($KEYP)
lw $Q2,8($KEYP)
lw $Q3,12($KEYP)
# no mix column now
@{[aes32esi4 $Q0,$T0,$T1,$T2,$T3]}
@{[aes32esi4 $Q1,$T1,$T2,$T3,$T0]}
@{[aes32esi4 $Q2,$T2,$T3,$T0,$T1]}
@{[aes32esi4 $Q3,$T3,$T0,$T1,$T2]}
# now Q0~Q3 hold the new state
sw $Q0,0($OUTP)
sw $Q1,4($OUTP)
sw $Q2,8($OUTP)
sw $Q3,12($OUTP)
# Pop registers and return
___
$code .= load_regs();
$code .= <<___;
ret
___
################################################################################
# void rv32i_zknd_decrypt(const unsigned char *in, unsigned char *out,
# const AES_KEY *key);
################################################################################
$code .= <<___;
.text
.balign 16
.globl rv32i_zknd_decrypt
.type rv32i_zknd_decrypt,\@function
rv32i_zknd_decrypt:
___
$code .= save_regs();
$code .= <<___;
# Load input to block cipher
lw $Q0,0($INP)
lw $Q1,4($INP)
lw $Q2,8($INP)
lw $Q3,12($INP)
# Load number of rounds
lw $loopcntr,240($KEYP)
# Load the last key
# use T0 as temporary now
slli $T0,$loopcntr,4
add $KEYP,$KEYP,$T0
# Load key
lw $T0,0($KEYP)
lw $T1,4($KEYP)
lw $T2,8($KEYP)
lw $T3,12($KEYP)
# initial transformation
xor $Q0,$Q0,$T0
xor $Q1,$Q1,$T1
xor $Q2,$Q2,$T2
xor $Q3,$Q3,$T3
# The main loop only executes the first N-2 rounds, each loop consumes two rounds
add $loopcntr,$loopcntr,-2
srli $loopcntr,$loopcntr,1
1:
# Grab next key in schedule
add $KEYP,$KEYP,-16
lw $T0,0($KEYP)
lw $T1,4($KEYP)
lw $T2,8($KEYP)
lw $T3,12($KEYP)
@{[aes32dsmi4 $T0,$Q0,$Q3,$Q2,$Q1]}
@{[aes32dsmi4 $T1,$Q1,$Q0,$Q3,$Q2]}
@{[aes32dsmi4 $T2,$Q2,$Q1,$Q0,$Q3]}
@{[aes32dsmi4 $T3,$Q3,$Q2,$Q1,$Q0]}
# now T0~T3 hold the new state
# Grab next key in schedule
add $KEYP,$KEYP,-16
lw $Q0,0($KEYP)
lw $Q1,4($KEYP)
lw $Q2,8($KEYP)
lw $Q3,12($KEYP)
@{[aes32dsmi4 $Q0,$T0,$T3,$T2,$T1]}
@{[aes32dsmi4 $Q1,$T1,$T0,$T3,$T2]}
@{[aes32dsmi4 $Q2,$T2,$T1,$T0,$T3]}
@{[aes32dsmi4 $Q3,$T3,$T2,$T1,$T0]}
# now Q0~Q3 hold the new state
add $loopcntr,$loopcntr,-1
bgtz $loopcntr,1b
# final two rounds
# Grab next key in schedule
add $KEYP,$KEYP,-16
lw $T0,0($KEYP)
lw $T1,4($KEYP)
lw $T2,8($KEYP)
lw $T3,12($KEYP)
@{[aes32dsmi4 $T0,$Q0,$Q3,$Q2,$Q1]}
@{[aes32dsmi4 $T1,$Q1,$Q0,$Q3,$Q2]}
@{[aes32dsmi4 $T2,$Q2,$Q1,$Q0,$Q3]}
@{[aes32dsmi4 $T3,$Q3,$Q2,$Q1,$Q0]}
# now T0~T3 hold the new state
# Grab next key in schedule
add $KEYP,$KEYP,-16
lw $Q0,0($KEYP)
lw $Q1,4($KEYP)
lw $Q2,8($KEYP)
lw $Q3,12($KEYP)
# no mix column now
@{[aes32dsi4 $Q0,$T0,$T3,$T2,$T1]}
@{[aes32dsi4 $Q1,$T1,$T0,$T3,$T2]}
@{[aes32dsi4 $Q2,$T2,$T1,$T0,$T3]}
@{[aes32dsi4 $Q3,$T3,$T2,$T1,$T0]}
# now Q0~Q3 hold the new state
sw $Q0,0($OUTP)
sw $Q1,4($OUTP)
sw $Q2,8($OUTP)
sw $Q3,12($OUTP)
# Pop registers and return
___
$code .= load_regs();
$code .= <<___;
ret
___
clear_regs();
################################################################################
# Register assignment for rv32i_zkn[e/d]_set_[en/de]crypt
################################################################################
# Function arguments (x10-x12 are a0-a2 in the ABI)
# Pointer to user key, number of bits in key, key pointer
my ($UKEY,$BITS,$KEYP) = use_regs(10..12);
# Temporaries
my ($T0,$T1,$T2,$T3,$T4,$T5,$T6,$T7,$T8) = use_regs(13..17,28..31);
################################################################################
# utility functions for rv32i_zkne_set_encrypt_key
################################################################################
my @rcon = (0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36);
# do 4 sbox on 4 bytes of rs, (possibly mix), then xor with rd
sub sbox4 {
my $inst = shift;
my $rd = shift;
my $rs = shift;
my $ret = <<___;
@{[$inst->($rd,$rd,$rs,0)]}
@{[$inst->($rd,$rd,$rs,1)]}
@{[$inst->($rd,$rd,$rs,2)]}
@{[$inst->($rd,$rd,$rs,3)]}
___
return $ret;
}
sub fwdsbox4 {
return sbox4(\&aes32esi, @_);
}
sub ke128enc {
my $zbkb = shift;
my $rnum = 0;
my $ret = '';
$ret .= <<___;
lw $T0,0($UKEY)
lw $T1,4($UKEY)
lw $T2,8($UKEY)
lw $T3,12($UKEY)
sw $T0,0($KEYP)
sw $T1,4($KEYP)
sw $T2,8($KEYP)
sw $T3,12($KEYP)
___
while($rnum < 10) {
$ret .= <<___;
# use T4 to store rcon
li $T4,$rcon[$rnum]
# as xor is associative and commutative
# we fist xor T0 with RCON, then use T0 to
# xor the result of each SBOX result of T3
xor $T0,$T0,$T4
# use T4 to store rotated T3
___
# right rotate by 8
if ($zbkb) {
$ret .= <<___;
@{[rori $T4,$T3,8]}
___
} else {
$ret .= <<___;
srli $T4,$T3,8
slli $T5,$T3,24
or $T4,$T4,$T5
___
}
$ret .= <<___;
# update T0
@{[fwdsbox4 $T0,$T4]}
# update new T1~T3
xor $T1,$T1,$T0
xor $T2,$T2,$T1
xor $T3,$T3,$T2
add $KEYP,$KEYP,16
sw $T0,0($KEYP)
sw $T1,4($KEYP)
sw $T2,8($KEYP)
sw $T3,12($KEYP)
___
$rnum++;
}
return $ret;
}
sub ke192enc {
my $zbkb = shift;
my $rnum = 0;
my $ret = '';
$ret .= <<___;
lw $T0,0($UKEY)
lw $T1,4($UKEY)
lw $T2,8($UKEY)
lw $T3,12($UKEY)
lw $T4,16($UKEY)
lw $T5,20($UKEY)
sw $T0,0($KEYP)
sw $T1,4($KEYP)
sw $T2,8($KEYP)
sw $T3,12($KEYP)
sw $T4,16($KEYP)
sw $T5,20($KEYP)
___
while($rnum < 8) {
$ret .= <<___;
# see the comment in ke128enc
li $T6,$rcon[$rnum]
xor $T0,$T0,$T6
___
# right rotate by 8
if ($zbkb) {
$ret .= <<___;
@{[rori $T6,$T5,8]}
___
} else {
$ret .= <<___;
srli $T6,$T5,8
slli $T7,$T5,24
or $T6,$T6,$T7
___
}
$ret .= <<___;
@{[fwdsbox4 $T0,$T6]}
xor $T1,$T1,$T0
xor $T2,$T2,$T1
xor $T3,$T3,$T2
___
if ($rnum != 7) {
# note that (8+1)*24 = 216, (12+1)*16 = 208
# thus the last 8 bytes can be dropped
$ret .= <<___;
xor $T4,$T4,$T3
xor $T5,$T5,$T4
___
}
$ret .= <<___;
add $KEYP,$KEYP,24
sw $T0,0($KEYP)
sw $T1,4($KEYP)
sw $T2,8($KEYP)
sw $T3,12($KEYP)
___
if ($rnum != 7) {
$ret .= <<___;
sw $T4,16($KEYP)
sw $T5,20($KEYP)
___
}
$rnum++;
}
return $ret;
}
sub ke256enc {
my $zbkb = shift;
my $rnum = 0;
my $ret = '';
$ret .= <<___;
lw $T0,0($UKEY)
lw $T1,4($UKEY)
lw $T2,8($UKEY)
lw $T3,12($UKEY)
lw $T4,16($UKEY)
lw $T5,20($UKEY)
lw $T6,24($UKEY)
lw $T7,28($UKEY)
sw $T0,0($KEYP)
sw $T1,4($KEYP)
sw $T2,8($KEYP)
sw $T3,12($KEYP)
sw $T4,16($KEYP)
sw $T5,20($KEYP)
sw $T6,24($KEYP)
sw $T7,28($KEYP)
___
while($rnum < 7) {
$ret .= <<___;
# see the comment in ke128enc
li $T8,$rcon[$rnum]
xor $T0,$T0,$T8
___
# right rotate by 8
if ($zbkb) {
$ret .= <<___;
@{[rori $T8,$T7,8]}
___
} else {
$ret .= <<___;
srli $T8,$T7,8
slli $BITS,$T7,24
or $T8,$T8,$BITS
___
}
$ret .= <<___;
@{[fwdsbox4 $T0,$T8]}
xor $T1,$T1,$T0
xor $T2,$T2,$T1
xor $T3,$T3,$T2
add $KEYP,$KEYP,32
sw $T0,0($KEYP)
sw $T1,4($KEYP)
sw $T2,8($KEYP)
sw $T3,12($KEYP)
___
if ($rnum != 6) {
# note that (7+1)*32 = 256, (14+1)*16 = 240
# thus the last 16 bytes can be dropped
$ret .= <<___;
# for aes256, T3->T4 needs 4sbox but no rotate/rcon
@{[fwdsbox4 $T4,$T3]}
xor $T5,$T5,$T4
xor $T6,$T6,$T5
xor $T7,$T7,$T6
sw $T4,16($KEYP)
sw $T5,20($KEYP)
sw $T6,24($KEYP)
sw $T7,28($KEYP)
___
}
$rnum++;
}
return $ret;
}
################################################################################
# void rv32i_zkne_set_encrypt_key(const unsigned char *userKey, const int bits,
# AES_KEY *key)
################################################################################
sub AES_set_common {
my ($ke128, $ke192, $ke256) = @_;
my $ret = '';
$ret .= <<___;
bnez $UKEY,1f # if (!userKey || !key) return -1;
bnez $KEYP,1f
li a0,-1
ret
1:
# Determine number of rounds from key size in bits
li $T0,128
bne $BITS,$T0,1f
li $T1,10 # key->rounds = 10 if bits == 128
sw $T1,240($KEYP) # store key->rounds
$ke128
j 4f
1:
li $T0,192
bne $BITS,$T0,2f
li $T1,12 # key->rounds = 12 if bits == 192
sw $T1,240($KEYP) # store key->rounds
$ke192
j 4f
2:
li $T1,14 # key->rounds = 14 if bits == 256
li $T0,256
beq $BITS,$T0,3f
li a0,-2 # If bits != 128, 192, or 256, return -2
j 5f
3:
sw $T1,240($KEYP) # store key->rounds
$ke256
4: # return 0
li a0,0
5: # return a0
___
return $ret;
}
$code .= <<___;
.text
.balign 16
.globl rv32i_zkne_set_encrypt_key
.type rv32i_zkne_set_encrypt_key,\@function
rv32i_zkne_set_encrypt_key:
___
$code .= save_regs();
$code .= AES_set_common(ke128enc(0), ke192enc(0),ke256enc(0));
$code .= load_regs();
$code .= <<___;
ret
___
################################################################################
# void rv32i_zbkb_zkne_set_encrypt_key(const unsigned char *userKey,
# const int bits, AES_KEY *key)
################################################################################
$code .= <<___;
.text
.balign 16
.globl rv32i_zbkb_zkne_set_encrypt_key
.type rv32i_zbkb_zkne_set_encrypt_key,\@function
rv32i_zbkb_zkne_set_encrypt_key:
___
$code .= save_regs();
$code .= AES_set_common(ke128enc(1), ke192enc(1),ke256enc(1));
$code .= load_regs();
$code .= <<___;
ret
___
################################################################################
# utility functions for rv32i_zknd_zkne_set_decrypt_key
################################################################################
sub invm4 {
# fwd sbox then inv sbox then mix column
# the result is only mix column
# this simulates aes64im T0
my $rd = shift;
my $tmp = shift;
my $rs = shift;
my $ret = <<___;
li $tmp,0
li $rd,0
@{[fwdsbox4 $tmp,$rs]}
@{[sbox4(\&aes32dsmi, $rd,$tmp)]}
___
return $ret;
}
sub ke128dec {
my $zbkb = shift;
my $rnum = 0;
my $ret = '';
$ret .= <<___;
lw $T0,0($UKEY)
lw $T1,4($UKEY)
lw $T2,8($UKEY)
lw $T3,12($UKEY)
sw $T0,0($KEYP)
sw $T1,4($KEYP)
sw $T2,8($KEYP)
sw $T3,12($KEYP)
___
while($rnum < 10) {
$ret .= <<___;
# see comments in ke128enc
li $T4,$rcon[$rnum]
xor $T0,$T0,$T4
___
# right rotate by 8
if ($zbkb) {
$ret .= <<___;
@{[rori $T4,$T3,8]}
___
} else {
$ret .= <<___;
srli $T4,$T3,8
slli $T5,$T3,24
or $T4,$T4,$T5
___
}
$ret .= <<___;
@{[fwdsbox4 $T0,$T4]}
xor $T1,$T1,$T0
xor $T2,$T2,$T1
xor $T3,$T3,$T2
add $KEYP,$KEYP,16
___
# need to mixcolumn only for [1:N-1] round keys
# this is from the fact that aes32dsmi subwords first then mix column
# intuitively decryption needs to first mix column then subwords
# however, for merging datapaths (encryption first subwords then mix column)
# aes32dsmi chooses to inverse the order of them, thus
# transform should then be done on the round key
if ($rnum < 9) {
$ret .= <<___;
# T4 and T5 are temp variables
@{[invm4 $T5,$T4,$T0]}
sw $T5,0($KEYP)
@{[invm4 $T5,$T4,$T1]}
sw $T5,4($KEYP)
@{[invm4 $T5,$T4,$T2]}
sw $T5,8($KEYP)
@{[invm4 $T5,$T4,$T3]}
sw $T5,12($KEYP)
___
} else {
$ret .= <<___;
sw $T0,0($KEYP)
sw $T1,4($KEYP)
sw $T2,8($KEYP)
sw $T3,12($KEYP)
___
}
$rnum++;
}
return $ret;
}
sub ke192dec {
my $zbkb = shift;
my $rnum = 0;
my $ret = '';
$ret .= <<___;
lw $T0,0($UKEY)
lw $T1,4($UKEY)
lw $T2,8($UKEY)
lw $T3,12($UKEY)
lw $T4,16($UKEY)
lw $T5,20($UKEY)
sw $T0,0($KEYP)
sw $T1,4($KEYP)
sw $T2,8($KEYP)
sw $T3,12($KEYP)
# see the comment in ke128dec
# T7 and T6 are temp variables
@{[invm4 $T7,$T6,$T4]}
sw $T7,16($KEYP)
@{[invm4 $T7,$T6,$T5]}
sw $T7,20($KEYP)
___
while($rnum < 8) {
$ret .= <<___;
# see the comment in ke128enc
li $T6,$rcon[$rnum]
xor $T0,$T0,$T6
___
# right rotate by 8
if ($zbkb) {
$ret .= <<___;
@{[rori $T6,$T5,8]}
___
} else {
$ret .= <<___;
srli $T6,$T5,8
slli $T7,$T5,24
or $T6,$T6,$T7
___
}
$ret .= <<___;
@{[fwdsbox4 $T0,$T6]}
xor $T1,$T1,$T0
xor $T2,$T2,$T1
xor $T3,$T3,$T2
add $KEYP,$KEYP,24
___
if ($rnum < 7) {
$ret .= <<___;
xor $T4,$T4,$T3
xor $T5,$T5,$T4
# see the comment in ke128dec
# T7 and T6 are temp variables
@{[invm4 $T7,$T6,$T0]}
sw $T7,0($KEYP)
@{[invm4 $T7,$T6,$T1]}
sw $T7,4($KEYP)
@{[invm4 $T7,$T6,$T2]}
sw $T7,8($KEYP)
@{[invm4 $T7,$T6,$T3]}
sw $T7,12($KEYP)
@{[invm4 $T7,$T6,$T4]}
sw $T7,16($KEYP)
@{[invm4 $T7,$T6,$T5]}
sw $T7,20($KEYP)
___
} else { # rnum == 7
$ret .= <<___;
# the reason for dropping T4/T5 is in ke192enc
# the reason for not invm4 is in ke128dec
sw $T0,0($KEYP)
sw $T1,4($KEYP)
sw $T2,8($KEYP)
sw $T3,12($KEYP)
___
}
$rnum++;
}
return $ret;
}
sub ke256dec {
my $zbkb = shift;
my $rnum = 0;
my $ret = '';
$ret .= <<___;
lw $T0,0($UKEY)
lw $T1,4($UKEY)
lw $T2,8($UKEY)
lw $T3,12($UKEY)
lw $T4,16($UKEY)
lw $T5,20($UKEY)
lw $T6,24($UKEY)
lw $T7,28($UKEY)
sw $T0,0($KEYP)
sw $T1,4($KEYP)
sw $T2,8($KEYP)
sw $T3,12($KEYP)
# see the comment in ke128dec
# BITS and T8 are temp variables
# BITS are not used anymore
@{[invm4 $T8,$BITS,$T4]}
sw $T8,16($KEYP)
@{[invm4 $T8,$BITS,$T5]}
sw $T8,20($KEYP)
@{[invm4 $T8,$BITS,$T6]}
sw $T8,24($KEYP)
@{[invm4 $T8,$BITS,$T7]}
sw $T8,28($KEYP)
___
while($rnum < 7) {
$ret .= <<___;
# see the comment in ke128enc
li $T8,$rcon[$rnum]
xor $T0,$T0,$T8
___
# right rotate by 8
if ($zbkb) {
$ret .= <<___;
@{[rori $T8,$T7,8]}
___
} else {
$ret .= <<___;
srli $T8,$T7,8
slli $BITS,$T7,24
or $T8,$T8,$BITS
___
}
$ret .= <<___;
@{[fwdsbox4 $T0,$T8]}
xor $T1,$T1,$T0
xor $T2,$T2,$T1
xor $T3,$T3,$T2
add $KEYP,$KEYP,32
___
if ($rnum < 6) {
$ret .= <<___;
# for aes256, T3->T4 needs 4sbox but no rotate/rcon
@{[fwdsbox4 $T4,$T3]}
xor $T5,$T5,$T4
xor $T6,$T6,$T5
xor $T7,$T7,$T6
# see the comment in ke128dec
# T8 and BITS are temp variables
@{[invm4 $T8,$BITS,$T0]}
sw $T8,0($KEYP)
@{[invm4 $T8,$BITS,$T1]}
sw $T8,4($KEYP)
@{[invm4 $T8,$BITS,$T2]}
sw $T8,8($KEYP)
@{[invm4 $T8,$BITS,$T3]}
sw $T8,12($KEYP)
@{[invm4 $T8,$BITS,$T4]}
sw $T8,16($KEYP)
@{[invm4 $T8,$BITS,$T5]}
sw $T8,20($KEYP)
@{[invm4 $T8,$BITS,$T6]}
sw $T8,24($KEYP)
@{[invm4 $T8,$BITS,$T7]}
sw $T8,28($KEYP)
___
} else {
$ret .= <<___;
sw $T0,0($KEYP)
sw $T1,4($KEYP)
sw $T2,8($KEYP)
sw $T3,12($KEYP)
# last 16 bytes are dropped
# see the comment in ke256enc
___
}
$rnum++;
}
return $ret;
}
################################################################################
# void rv32i_zknd_zkne_set_decrypt_key(const unsigned char *userKey, const int bits,
# AES_KEY *key)
################################################################################
# a note on naming: set_decrypt_key needs aes32esi thus add zkne on name
$code .= <<___;
.text
.balign 16
.globl rv32i_zknd_zkne_set_decrypt_key
.type rv32i_zknd_zkne_set_decrypt_key,\@function
rv32i_zknd_zkne_set_decrypt_key:
___
$code .= save_regs();
$code .= AES_set_common(ke128dec(0), ke192dec(0),ke256dec(0));
$code .= load_regs();
$code .= <<___;
ret
___
################################################################################
# void rv32i_zbkb_zknd_zkne_set_decrypt_key(const unsigned char *userKey,
# const int bits, AES_KEY *key)
################################################################################
$code .= <<___;
.text
.balign 16
.globl rv32i_zbkb_zknd_zkne_set_decrypt_key
.type rv32i_zbkb_zknd_zkne_set_decrypt_key,\@function
rv32i_zbkb_zknd_zkne_set_decrypt_key:
___
$code .= save_regs();
$code .= AES_set_common(ke128dec(1), ke192dec(1),ke256dec(1));
$code .= load_regs();
$code .= <<___;
ret
___
print $code;
close STDOUT or die "error closing STDOUT: $!";