#!/usr/bin/env perl
#
# ====================================================================
# Written by Andy Polyakov <appro@fy.chalmers.se> 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/.
# ====================================================================
#
# Wrapper around 'rep montmul', VIA-specific instruction accessing
# PadLock Montgomery Multiplier. The wrapper is designed as drop-in
# replacement for OpenSSL bn_mul_mont [first implemented in 0.9.9].
#
# Below are interleaved outputs from 'openssl speed rsa dsa' for 4
# different software configurations on 1.5GHz VIA Esther processor.
# Lines marked with "software integer" denote performance of hand-
# coded integer-only assembler found in OpenSSL 0.9.7. "Software SSE2"
# refers to hand-coded SSE2 Montgomery multiplication procedure found
# OpenSSL 0.9.9. "Hardware VIA SDK" refers to padlock_pmm routine from
# Padlock SDK 2.0.1 available for download from VIA, which naturally
# utilizes the magic 'repz montmul' instruction. And finally "hardware
# this" refers to *this* implementation which also uses 'repz montmul'
#
# sign verify sign/s verify/s
# rsa 512 bits 0.001720s 0.000140s 581.4 7149.7 software integer
# rsa 512 bits 0.000690s 0.000086s 1450.3 11606.0 software SSE2
# rsa 512 bits 0.006136s 0.000201s 163.0 4974.5 hardware VIA SDK
# rsa 512 bits 0.000712s 0.000050s 1404.9 19858.5 hardware this
#
# rsa 1024 bits 0.008518s 0.000413s 117.4 2420.8 software integer
# rsa 1024 bits 0.004275s 0.000277s 233.9 3609.7 software SSE2
# rsa 1024 bits 0.012136s 0.000260s 82.4 3844.5 hardware VIA SDK
# rsa 1024 bits 0.002522s 0.000116s 396.5 8650.9 hardware this
#
# rsa 2048 bits 0.050101s 0.001371s 20.0 729.6 software integer
# rsa 2048 bits 0.030273s 0.001008s 33.0 991.9 software SSE2
# rsa 2048 bits 0.030833s 0.000976s 32.4 1025.1 hardware VIA SDK
# rsa 2048 bits 0.011879s 0.000342s 84.2 2921.7 hardware this
#
# rsa 4096 bits 0.327097s 0.004859s 3.1 205.8 software integer
# rsa 4096 bits 0.229318s 0.003859s 4.4 259.2 software SSE2
# rsa 4096 bits 0.233953s 0.003274s 4.3 305.4 hardware VIA SDK
# rsa 4096 bits 0.070493s 0.001166s 14.2 857.6 hardware this
#
# dsa 512 bits 0.001342s 0.001651s 745.2 605.7 software integer
# dsa 512 bits 0.000844s 0.000987s 1185.3 1013.1 software SSE2
# dsa 512 bits 0.001902s 0.002247s 525.6 444.9 hardware VIA SDK
# dsa 512 bits 0.000458s 0.000524s 2182.2 1909.1 hardware this
#
# dsa 1024 bits 0.003964s 0.004926s 252.3 203.0 software integer
# dsa 1024 bits 0.002686s 0.003166s 372.3 315.8 software SSE2
# dsa 1024 bits 0.002397s 0.002823s 417.1 354.3 hardware VIA SDK
# dsa 1024 bits 0.000978s 0.001170s 1022.2 855.0 hardware this
#
# dsa 2048 bits 0.013280s 0.016518s 75.3 60.5 software integer
# dsa 2048 bits 0.009911s 0.011522s 100.9 86.8 software SSE2
# dsa 2048 bits 0.009542s 0.011763s 104.8 85.0 hardware VIA SDK
# dsa 2048 bits 0.002884s 0.003352s 346.8 298.3 hardware this
#
# To give you some other reference point here is output for 2.4GHz P4
# running hand-coded SSE2 bn_mul_mont found in 0.9.9, i.e. "software
# SSE2" in above terms.
#
# rsa 512 bits 0.000407s 0.000047s 2454.2 21137.0
# rsa 1024 bits 0.002426s 0.000141s 412.1 7100.0
# rsa 2048 bits 0.015046s 0.000491s 66.5 2034.9
# rsa 4096 bits 0.109770s 0.002379s 9.1 420.3
# dsa 512 bits 0.000438s 0.000525s 2281.1 1904.1
# dsa 1024 bits 0.001346s 0.001595s 742.7 627.0
# dsa 2048 bits 0.004745s 0.005582s 210.7 179.1
#
# Conclusions:
# - VIA SDK leaves a *lot* of room for improvement (which this
# implementation successfully fills:-);
# - 'rep montmul' gives up to >3x performance improvement depending on
# key length;
# - in terms of absolute performance it delivers approximately as much
# as modern out-of-order 32-bit cores [again, for longer keys].
$0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1;
push(@INC,"${dir}","${dir}../../perlasm");
require "x86asm.pl";
&asm_init($ARGV[0],"via-mont.pl");
# int bn_mul_mont(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp, const BN_ULONG *np,const BN_ULONG *n0, int num);
$func="bn_mul_mont_padlock";
$pad=16*1; # amount of reserved bytes on top of every vector
# stack layout
$mZeroPrime=&DWP(0,"esp"); # these are specified by VIA
$A=&DWP(4,"esp");
$B=&DWP(8,"esp");
$T=&DWP(12,"esp");
$M=&DWP(16,"esp");
$scratch=&DWP(20,"esp");
$rp=&DWP(24,"esp"); # these are mine
$sp=&DWP(28,"esp");
# &DWP(32,"esp") # 32 byte scratch area
# &DWP(64+(4*$num+$pad)*0,"esp") # padded tp[num]
# &DWP(64+(4*$num+$pad)*1,"esp") # padded copy of ap[num]
# &DWP(64+(4*$num+$pad)*2,"esp") # padded copy of bp[num]
# &DWP(64+(4*$num+$pad)*3,"esp") # padded copy of np[num]
# Note that SDK suggests to unconditionally allocate 2K per vector. This
# has quite an impact on performance. It naturally depends on key length,
# but to give an example 1024 bit private RSA key operations suffer >30%
# penalty. I allocate only as much as actually required...
&function_begin($func);
&xor ("eax","eax");
&mov ("ecx",&wparam(5)); # num
# meet VIA's limitations for num [note that the specification
# expresses them in bits, while we work with amount of 32-bit words]
&test ("ecx",3);
&jnz (&label("leave")); # num % 4 != 0
&cmp ("ecx",8);
&jb (&label("leave")); # num < 8
&cmp ("ecx",1024);
&ja (&label("leave")); # num > 1024
&pushf ();
&cld ();
&mov ("edi",&wparam(0)); # rp
&mov ("eax",&wparam(1)); # ap
&mov ("ebx",&wparam(2)); # bp
&mov ("edx",&wparam(3)); # np
&mov ("esi",&wparam(4)); # n0
&mov ("esi",&DWP(0,"esi")); # *n0
&lea ("ecx",&DWP($pad,"","ecx",4)); # ecx becomes vector size in bytes
&lea ("ebp",&DWP(64,"","ecx",4)); # allocate 4 vectors + 64 bytes
&neg ("ebp");
&add ("ebp","esp");
&and ("ebp",-64); # align to cache-line
&xchg ("ebp","esp"); # alloca
&mov ($rp,"edi"); # save rp
&mov ($sp,"ebp"); # save esp
&mov ($mZeroPrime,"esi");
&lea ("esi",&DWP(64,"esp")); # tp
&mov ($T,"esi");
&lea ("edi",&DWP(32,"esp")); # scratch area
&mov ($scratch,"edi");
&mov ("esi","eax");
&lea ("ebp",&DWP(-$pad,"ecx"));
&shr ("ebp",2); # restore original num value in ebp
&xor ("eax","eax");
&mov ("ecx","ebp");
&lea ("ecx",&DWP((32+$pad)/4,"ecx"));# padded tp + scratch
&data_byte(0xf3,0xab); # rep stosl, bzero
&mov ("ecx","ebp");
&lea ("edi",&DWP(64+$pad,"esp","ecx",4));# pointer to ap copy
&mov ($A,"edi");
&data_byte(0xf3,0xa5); # rep movsl, memcpy
&mov ("ecx",$pad/4);
&data_byte(0xf3,0xab); # rep stosl, bzero pad
# edi points at the end of padded ap copy...
&mov ("ecx","ebp");
&mov ("esi","ebx");
&mov ($B,"edi");
&data_byte(0xf3,0xa5); # rep movsl, memcpy
&mov ("ecx",$pad/4);
&data_byte(0xf3,0xab); # rep stosl, bzero pad
# edi points at the end of padded bp copy...
&mov ("ecx","ebp");
&mov ("esi","edx");
&mov ($M,"edi");
&data_byte(0xf3,0xa5); # rep movsl, memcpy
&mov ("ecx",$pad/4);
&data_byte(0xf3,0xab); # rep stosl, bzero pad
# edi points at the end of padded np copy...
# let magic happen...
&mov ("ecx","ebp");
&mov ("esi","esp");
&shl ("ecx",5); # convert word counter to bit counter
&align (4);
&data_byte(0xf3,0x0f,0xa6,0xc0);# rep montmul
&mov ("ecx","ebp");
&lea ("esi",&DWP(64,"esp")); # tp
# edi still points at the end of padded np copy...
&neg ("ebp");
&lea ("ebp",&DWP(-$pad,"edi","ebp",4)); # so just "rewind"
&mov ("edi",$rp); # restore rp
&xor ("edx","edx"); # i=0 and clear CF
&set_label("sub",8);
&mov ("eax",&DWP(0,"esi","edx",4));
&sbb ("eax",&DWP(0,"ebp","edx",4));
&mov (&DWP(0,"edi","edx",4),"eax"); # rp[i]=tp[i]-np[i]
&lea ("edx",&DWP(1,"edx")); # i++
&loop (&label("sub")); # doesn't affect CF!
&mov ("eax",&DWP(0,"esi","edx",4)); # upmost overflow bit
&sbb ("eax",0);
&and ("esi","eax");
¬ ("eax");
&mov ("ebp","edi");
&and ("ebp","eax");
&or ("esi","ebp"); # tp=carry?tp:rp
&mov ("ecx","edx"); # num
&xor ("edx","edx"); # i=0
&set_label("copy",8);
&mov ("eax",&DWP(0,"esi","edx",4));
&mov (&DWP(64,"esp","edx",4),"ecx"); # zap tp
&mov (&DWP(0,"edi","edx",4),"eax");
&lea ("edx",&DWP(1,"edx")); # i++
&loop (&label("copy"));
&mov ("ebp",$sp);
&xor ("eax","eax");
&mov ("ecx",64/4);
&mov ("edi","esp"); # zap frame including scratch area
&data_byte(0xf3,0xab); # rep stosl, bzero
# zap copies of ap, bp and np
&lea ("edi",&DWP(64+$pad,"esp","edx",4));# pointer to ap
&lea ("ecx",&DWP(3*$pad/4,"edx","edx",2));
&data_byte(0xf3,0xab); # rep stosl, bzero
&mov ("esp","ebp");
&inc ("eax"); # signal "done"
&popf ();
&set_label("leave");
&function_end($func);
&asciz("Padlock Montgomery Multiplication, CRYPTOGAMS by <appro\@openssl.org>");
&asm_finish();