openssl/crypto/bn/asm/mips-mont.pl
Andy Polyakov 774ff8fed6 bn/asm/*-mont.pl: harmonize with BN_from_montgomery_word.
Montgomery multiplication post-conditions in some of code paths were
formally non-constant time. Cache access pattern was result-neutral,
but a little bit asymmetric, which might have produced a signal [if
processor reordered load and stores at run-time].

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6141)
2018-05-02 21:55:21 +02:00

434 lines
9.3 KiB
Raku
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

#! /usr/bin/env perl
# Copyright 2010-2016 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/.
# ====================================================================
# This module doesn't present direct interest for OpenSSL, because it
# doesn't provide better performance for longer keys, at least not on
# in-order-execution cores. While 512-bit RSA sign operations can be
# 65% faster in 64-bit mode, 1024-bit ones are only 15% faster, and
# 4096-bit ones are up to 15% slower. In 32-bit mode it varies from
# 16% improvement for 512-bit RSA sign to -33% for 4096-bit RSA
# verify:-( All comparisons are against bn_mul_mont-free assembler.
# The module might be of interest to embedded system developers, as
# the code is smaller than 1KB, yet offers >3x improvement on MIPS64
# and 75-30% [less for longer keys] on MIPS32 over compiler-generated
# code.
######################################################################
# There is a number of MIPS ABI in use, O32 and N32/64 are most
# widely used. Then there is a new contender: NUBI. It appears that if
# one picks the latter, it's possible to arrange code in ABI neutral
# manner. Therefore let's stick to NUBI register layout:
#
($zero,$at,$t0,$t1,$t2)=map("\$$_",(0..2,24,25));
($a0,$a1,$a2,$a3,$a4,$a5,$a6,$a7)=map("\$$_",(4..11));
($s0,$s1,$s2,$s3,$s4,$s5,$s6,$s7,$s8,$s9,$s10,$s11)=map("\$$_",(12..23));
($gp,$tp,$sp,$fp,$ra)=map("\$$_",(3,28..31));
#
# The return value is placed in $a0. Following coding rules facilitate
# interoperability:
#
# - never ever touch $tp, "thread pointer", former $gp;
# - copy return value to $t0, former $v0 [or to $a0 if you're adapting
# old code];
# - on O32 populate $a4-$a7 with 'lw $aN,4*N($sp)' if necessary;
#
# For reference here is register layout for N32/64 MIPS ABIs:
#
# ($zero,$at,$v0,$v1)=map("\$$_",(0..3));
# ($a0,$a1,$a2,$a3,$a4,$a5,$a6,$a7)=map("\$$_",(4..11));
# ($t0,$t1,$t2,$t3,$t8,$t9)=map("\$$_",(12..15,24,25));
# ($s0,$s1,$s2,$s3,$s4,$s5,$s6,$s7)=map("\$$_",(16..23));
# ($gp,$sp,$fp,$ra)=map("\$$_",(28..31));
#
$flavour = shift || "o32"; # supported flavours are o32,n32,64,nubi32,nubi64
if ($flavour =~ /64|n32/i) {
$PTR_ADD="daddu"; # incidentally works even on n32
$PTR_SUB="dsubu"; # incidentally works even on n32
$REG_S="sd";
$REG_L="ld";
$SZREG=8;
} else {
$PTR_ADD="addu";
$PTR_SUB="subu";
$REG_S="sw";
$REG_L="lw";
$SZREG=4;
}
$SAVED_REGS_MASK = ($flavour =~ /nubi/i) ? 0x00fff000 : 0x00ff0000;
#
# <appro@openssl.org>
#
######################################################################
while (($output=shift) && ($output!~/\w[\w\-]*\.\w+$/)) {}
open STDOUT,">$output";
if ($flavour =~ /64|n32/i) {
$LD="ld";
$ST="sd";
$MULTU="dmultu";
$ADDU="daddu";
$SUBU="dsubu";
$BNSZ=8;
} else {
$LD="lw";
$ST="sw";
$MULTU="multu";
$ADDU="addu";
$SUBU="subu";
$BNSZ=4;
}
# int bn_mul_mont(
$rp=$a0; # BN_ULONG *rp,
$ap=$a1; # const BN_ULONG *ap,
$bp=$a2; # const BN_ULONG *bp,
$np=$a3; # const BN_ULONG *np,
$n0=$a4; # const BN_ULONG *n0,
$num=$a5; # int num);
$lo0=$a6;
$hi0=$a7;
$lo1=$t1;
$hi1=$t2;
$aj=$s0;
$bi=$s1;
$nj=$s2;
$tp=$s3;
$alo=$s4;
$ahi=$s5;
$nlo=$s6;
$nhi=$s7;
$tj=$s8;
$i=$s9;
$j=$s10;
$m1=$s11;
$FRAMESIZE=14;
$code=<<___;
#include "mips_arch.h"
.text
.set noat
.set noreorder
.align 5
.globl bn_mul_mont
.ent bn_mul_mont
bn_mul_mont:
___
$code.=<<___ if ($flavour =~ /o32/i);
lw $n0,16($sp)
lw $num,20($sp)
___
$code.=<<___;
slt $at,$num,4
bnez $at,1f
li $t0,0
slt $at,$num,17 # on in-order CPU
bnez $at,bn_mul_mont_internal
nop
1: jr $ra
li $a0,0
.end bn_mul_mont
.align 5
.ent bn_mul_mont_internal
bn_mul_mont_internal:
.frame $fp,$FRAMESIZE*$SZREG,$ra
.mask 0x40000000|$SAVED_REGS_MASK,-$SZREG
$PTR_SUB $sp,$FRAMESIZE*$SZREG
$REG_S $fp,($FRAMESIZE-1)*$SZREG($sp)
$REG_S $s11,($FRAMESIZE-2)*$SZREG($sp)
$REG_S $s10,($FRAMESIZE-3)*$SZREG($sp)
$REG_S $s9,($FRAMESIZE-4)*$SZREG($sp)
$REG_S $s8,($FRAMESIZE-5)*$SZREG($sp)
$REG_S $s7,($FRAMESIZE-6)*$SZREG($sp)
$REG_S $s6,($FRAMESIZE-7)*$SZREG($sp)
$REG_S $s5,($FRAMESIZE-8)*$SZREG($sp)
$REG_S $s4,($FRAMESIZE-9)*$SZREG($sp)
___
$code.=<<___ if ($flavour =~ /nubi/i);
$REG_S $s3,($FRAMESIZE-10)*$SZREG($sp)
$REG_S $s2,($FRAMESIZE-11)*$SZREG($sp)
$REG_S $s1,($FRAMESIZE-12)*$SZREG($sp)
$REG_S $s0,($FRAMESIZE-13)*$SZREG($sp)
___
$code.=<<___;
move $fp,$sp
.set reorder
$LD $n0,0($n0)
$LD $bi,0($bp) # bp[0]
$LD $aj,0($ap) # ap[0]
$LD $nj,0($np) # np[0]
$PTR_SUB $sp,2*$BNSZ # place for two extra words
sll $num,`log($BNSZ)/log(2)`
li $at,-4096
$PTR_SUB $sp,$num
and $sp,$at
$MULTU ($aj,$bi)
$LD $ahi,$BNSZ($ap)
$LD $nhi,$BNSZ($np)
mflo ($lo0,$aj,$bi)
mfhi ($hi0,$aj,$bi)
$MULTU ($lo0,$n0)
mflo ($m1,$lo0,$n0)
$MULTU ($ahi,$bi)
mflo ($alo,$ahi,$bi)
mfhi ($ahi,$ahi,$bi)
$MULTU ($nj,$m1)
mflo ($lo1,$nj,$m1)
mfhi ($hi1,$nj,$m1)
$MULTU ($nhi,$m1)
$ADDU $lo1,$lo0
sltu $at,$lo1,$lo0
$ADDU $hi1,$at
mflo ($nlo,$nhi,$m1)
mfhi ($nhi,$nhi,$m1)
move $tp,$sp
li $j,2*$BNSZ
.align 4
.L1st:
.set noreorder
$PTR_ADD $aj,$ap,$j
$PTR_ADD $nj,$np,$j
$LD $aj,($aj)
$LD $nj,($nj)
$MULTU ($aj,$bi)
$ADDU $lo0,$alo,$hi0
$ADDU $lo1,$nlo,$hi1
sltu $at,$lo0,$hi0
sltu $t0,$lo1,$hi1
$ADDU $hi0,$ahi,$at
$ADDU $hi1,$nhi,$t0
mflo ($alo,$aj,$bi)
mfhi ($ahi,$aj,$bi)
$ADDU $lo1,$lo0
sltu $at,$lo1,$lo0
$MULTU ($nj,$m1)
$ADDU $hi1,$at
addu $j,$BNSZ
$ST $lo1,($tp)
sltu $t0,$j,$num
mflo ($nlo,$nj,$m1)
mfhi ($nhi,$nj,$m1)
bnez $t0,.L1st
$PTR_ADD $tp,$BNSZ
.set reorder
$ADDU $lo0,$alo,$hi0
sltu $at,$lo0,$hi0
$ADDU $hi0,$ahi,$at
$ADDU $lo1,$nlo,$hi1
sltu $t0,$lo1,$hi1
$ADDU $hi1,$nhi,$t0
$ADDU $lo1,$lo0
sltu $at,$lo1,$lo0
$ADDU $hi1,$at
$ST $lo1,($tp)
$ADDU $hi1,$hi0
sltu $at,$hi1,$hi0
$ST $hi1,$BNSZ($tp)
$ST $at,2*$BNSZ($tp)
li $i,$BNSZ
.align 4
.Louter:
$PTR_ADD $bi,$bp,$i
$LD $bi,($bi)
$LD $aj,($ap)
$LD $ahi,$BNSZ($ap)
$LD $tj,($sp)
$MULTU ($aj,$bi)
$LD $nj,($np)
$LD $nhi,$BNSZ($np)
mflo ($lo0,$aj,$bi)
mfhi ($hi0,$aj,$bi)
$ADDU $lo0,$tj
$MULTU ($lo0,$n0)
sltu $at,$lo0,$tj
$ADDU $hi0,$at
mflo ($m1,$lo0,$n0)
$MULTU ($ahi,$bi)
mflo ($alo,$ahi,$bi)
mfhi ($ahi,$ahi,$bi)
$MULTU ($nj,$m1)
mflo ($lo1,$nj,$m1)
mfhi ($hi1,$nj,$m1)
$MULTU ($nhi,$m1)
$ADDU $lo1,$lo0
sltu $at,$lo1,$lo0
$ADDU $hi1,$at
mflo ($nlo,$nhi,$m1)
mfhi ($nhi,$nhi,$m1)
move $tp,$sp
li $j,2*$BNSZ
$LD $tj,$BNSZ($tp)
.align 4
.Linner:
.set noreorder
$PTR_ADD $aj,$ap,$j
$PTR_ADD $nj,$np,$j
$LD $aj,($aj)
$LD $nj,($nj)
$MULTU ($aj,$bi)
$ADDU $lo0,$alo,$hi0
$ADDU $lo1,$nlo,$hi1
sltu $at,$lo0,$hi0
sltu $t0,$lo1,$hi1
$ADDU $hi0,$ahi,$at
$ADDU $hi1,$nhi,$t0
mflo ($alo,$aj,$bi)
mfhi ($ahi,$aj,$bi)
$ADDU $lo0,$tj
addu $j,$BNSZ
$MULTU ($nj,$m1)
sltu $at,$lo0,$tj
$ADDU $lo1,$lo0
$ADDU $hi0,$at
sltu $t0,$lo1,$lo0
$LD $tj,2*$BNSZ($tp)
$ADDU $hi1,$t0
sltu $at,$j,$num
mflo ($nlo,$nj,$m1)
mfhi ($nhi,$nj,$m1)
$ST $lo1,($tp)
bnez $at,.Linner
$PTR_ADD $tp,$BNSZ
.set reorder
$ADDU $lo0,$alo,$hi0
sltu $at,$lo0,$hi0
$ADDU $hi0,$ahi,$at
$ADDU $lo0,$tj
sltu $t0,$lo0,$tj
$ADDU $hi0,$t0
$LD $tj,2*$BNSZ($tp)
$ADDU $lo1,$nlo,$hi1
sltu $at,$lo1,$hi1
$ADDU $hi1,$nhi,$at
$ADDU $lo1,$lo0
sltu $t0,$lo1,$lo0
$ADDU $hi1,$t0
$ST $lo1,($tp)
$ADDU $lo1,$hi1,$hi0
sltu $hi1,$lo1,$hi0
$ADDU $lo1,$tj
sltu $at,$lo1,$tj
$ADDU $hi1,$at
$ST $lo1,$BNSZ($tp)
$ST $hi1,2*$BNSZ($tp)
addu $i,$BNSZ
sltu $t0,$i,$num
bnez $t0,.Louter
.set noreorder
$PTR_ADD $tj,$sp,$num # &tp[num]
move $tp,$sp
move $ap,$sp
li $hi0,0 # clear borrow bit
.align 4
.Lsub: $LD $lo0,($tp)
$LD $lo1,($np)
$PTR_ADD $tp,$BNSZ
$PTR_ADD $np,$BNSZ
$SUBU $lo1,$lo0,$lo1 # tp[i]-np[i]
sgtu $at,$lo1,$lo0
$SUBU $lo0,$lo1,$hi0
sgtu $hi0,$lo0,$lo1
$ST $lo0,($rp)
or $hi0,$at
sltu $at,$tp,$tj
bnez $at,.Lsub
$PTR_ADD $rp,$BNSZ
$SUBU $hi0,$hi1,$hi0 # handle upmost overflow bit
move $tp,$sp
$PTR_SUB $rp,$num # restore rp
not $hi1,$hi0
.Lcopy: $LD $nj,($tp) # conditional move
$LD $aj,($rp)
$ST $zero,($tp)
$PTR_ADD $tp,$BNSZ
and $nj,$hi0
and $aj,$hi1
or $aj,$nj
sltu $at,$tp,$tj
$ST $aj,($rp)
bnez $at,.Lcopy
$PTR_ADD $rp,$BNSZ
li $a0,1
li $t0,1
.set noreorder
move $sp,$fp
$REG_L $fp,($FRAMESIZE-1)*$SZREG($sp)
$REG_L $s11,($FRAMESIZE-2)*$SZREG($sp)
$REG_L $s10,($FRAMESIZE-3)*$SZREG($sp)
$REG_L $s9,($FRAMESIZE-4)*$SZREG($sp)
$REG_L $s8,($FRAMESIZE-5)*$SZREG($sp)
$REG_L $s7,($FRAMESIZE-6)*$SZREG($sp)
$REG_L $s6,($FRAMESIZE-7)*$SZREG($sp)
$REG_L $s5,($FRAMESIZE-8)*$SZREG($sp)
$REG_L $s4,($FRAMESIZE-9)*$SZREG($sp)
___
$code.=<<___ if ($flavour =~ /nubi/i);
$REG_L $s3,($FRAMESIZE-10)*$SZREG($sp)
$REG_L $s2,($FRAMESIZE-11)*$SZREG($sp)
$REG_L $s1,($FRAMESIZE-12)*$SZREG($sp)
$REG_L $s0,($FRAMESIZE-13)*$SZREG($sp)
___
$code.=<<___;
jr $ra
$PTR_ADD $sp,$FRAMESIZE*$SZREG
.end bn_mul_mont_internal
.rdata
.asciiz "Montgomery Multiplication for MIPS, CRYPTOGAMS by <appro\@openssl.org>"
___
$code =~ s/\`([^\`]*)\`/eval $1/gem;
print $code;
close STDOUT;