From 361512da0d900ba276096cbd152e304d402aca65 Mon Sep 17 00:00:00 2001 From: Andy Polyakov Date: Fri, 12 Aug 2011 16:44:32 +0000 Subject: [PATCH] This commit completes recent modular exponentiation optimizations on x86_64 platform. It targets specifically RSA1024 sign (using ideas from http://eprint.iacr.org/2011/239) and adds more than 10% on most platforms. Overall performance improvement relative to 1.0.0 is ~40% in average, with best result of 54% on Westmere. Incidentally ~40% is average improvement even for longer key lengths. --- Configure | 7 +- TABLE | 24 +- crypto/bn/Makefile | 2 + crypto/bn/asm/x86_64-mont.pl | 5 +- crypto/bn/asm/x86_64-mont5.pl | 834 ++++++++++++++++++++++++++++++++++ crypto/bn/bn_exp.c | 190 ++++++-- 6 files changed, 1004 insertions(+), 58 deletions(-) create mode 100755 crypto/bn/asm/x86_64-mont5.pl diff --git a/Configure b/Configure index 8b5efd6b1b..9d9bd72b8b 100755 --- a/Configure +++ b/Configure @@ -127,7 +127,7 @@ my $x86_asm="x86cpuid.o:bn-586.o co-586.o x86-mont.o x86-gf2m.o:des-586.o crypt5 my $x86_elf_asm="$x86_asm:elf"; -my $x86_64_asm="x86_64cpuid.o:x86_64-gcc.o x86_64-mont.o x86_64-gf2m.o modexp512-x86_64.o::aes-x86_64.o aesni-x86_64.o::md5-x86_64.o:sha1-x86_64.o sha256-x86_64.o sha512-x86_64.o::rc4-x86_64.o:::wp-x86_64.o:cmll-x86_64.o cmll_misc.o:ghash-x86_64.o"; +my $x86_64_asm="x86_64cpuid.o:x86_64-gcc.o x86_64-mont.o x86_64-mont5.o x86_64-gf2m.o modexp512-x86_64.o::aes-x86_64.o aesni-x86_64.o::md5-x86_64.o:sha1-x86_64.o sha256-x86_64.o sha512-x86_64.o::rc4-x86_64.o:::wp-x86_64.o:cmll-x86_64.o cmll_misc.o:ghash-x86_64.o"; my $ia64_asm="ia64cpuid.o:bn-ia64.o ia64-mont.o::aes_core.o aes_cbc.o aes-ia64.o::md5-ia64.o:sha1-ia64.o sha256-ia64.o sha512-ia64.o::rc4-ia64.o rc4_skey.o:::::ghash-ia64.o:void"; my $sparcv9_asm="sparcv9cap.o sparccpuid.o:bn-sparcv9.o sparcv9-mont.o sparcv9a-mont.o:des_enc-sparc.o fcrypt_b.o:aes_core.o aes_cbc.o aes-sparcv9.o:::sha1-sparcv9.o sha256-sparcv9.o sha512-sparcv9.o:::::::ghash-sparcv9.o:void"; my $sparcv8_asm=":sparcv8.o:des_enc-sparc.o fcrypt_b.o::::::::::::void"; @@ -513,9 +513,9 @@ my %table=( # # Win64 targets, WIN64I denotes IA-64 and WIN64A - AMD64 "VC-WIN64I","cl:-W3 -Gs0 -Gy -nologo -DOPENSSL_SYSNAME_WIN32 -DWIN32_LEAN_AND_MEAN -DL_ENDIAN -DUNICODE -D_UNICODE -D_CRT_SECURE_NO_DEPRECATE:::WIN64I::SIXTY_FOUR_BIT RC4_CHUNK_LL DES_INT EXPORT_VAR_AS_FN:ia64cpuid.o:ia64.o ia64-mont.o::aes_core.o aes_cbc.o aes-ia64.o::md5-ia64.o:sha1-ia64.o sha256-ia64.o sha512-ia64.o:::::::ghash-ia64.o:ias:win32", -"VC-WIN64A","cl:-W3 -Gs0 -Gy -nologo -DOPENSSL_SYSNAME_WIN32 -DWIN32_LEAN_AND_MEAN -DL_ENDIAN -DUNICODE -D_UNICODE -D_CRT_SECURE_NO_DEPRECATE:::WIN64A::SIXTY_FOUR_BIT RC4_CHUNK_LL DES_INT EXPORT_VAR_AS_FN:x86_64cpuid.o:bn_asm.o x86_64-mont.o::aes-x86_64.o aesni-x86_64.o::md5-x86_64.o:sha1-x86_64.o sha256-x86_64.o sha512-x86_64.o::rc4-x86_64.o:::wp-x86_64.o:cmll-x86_64.o cmll_misc.o:ghash-x86_64.o:auto:win32", +"VC-WIN64A","cl:-W3 -Gs0 -Gy -nologo -DOPENSSL_SYSNAME_WIN32 -DWIN32_LEAN_AND_MEAN -DL_ENDIAN -DUNICODE -D_UNICODE -D_CRT_SECURE_NO_DEPRECATE:::WIN64A::SIXTY_FOUR_BIT RC4_CHUNK_LL DES_INT EXPORT_VAR_AS_FN:".eval{my $asm=$x86_64_asm;$asm=~s/x86_64-gcc\.o/bn_asm.o/;$asm}.":auto:win32", "debug-VC-WIN64I","cl:-W3 -Gs0 -Gy -Zi -nologo -DOPENSSL_SYSNAME_WIN32 -DWIN32_LEAN_AND_MEAN -DL_ENDIAN -DUNICODE -D_UNICODE -D_CRT_SECURE_NO_DEPRECATE:::WIN64I::SIXTY_FOUR_BIT RC4_CHUNK_LL DES_INT EXPORT_VAR_AS_FN:ia64cpuid.o:ia64.o::aes_core.o aes_cbc.o aes-ia64.o::md5-ia64.o:sha1-ia64.o sha256-ia64.o sha512-ia64.o:::::::ghash-ia64.o:ias:win32", -"debug-VC-WIN64A","cl:-W3 -Gs0 -Gy -Zi -nologo -DOPENSSL_SYSNAME_WIN32 -DWIN32_LEAN_AND_MEAN -DL_ENDIAN -DUNICODE -D_UNICODE -D_CRT_SECURE_NO_DEPRECATE:::WIN64A::SIXTY_FOUR_BIT RC4_CHUNK_LL DES_INT EXPORT_VAR_AS_FN:x86_64cpuid.o:bn_asm.o x86_64-mont.o::aes-x86_64.o::md5-x86_64.o:sha1-x86_64.o sha256-x86_64.o sha512-x86_64.o::rc4-x86_64.o:::wp-x86_64.o:cmll-x86_64.o cmll_misc.o:ghash-x86_64.o:auto:win32", +"debug-VC-WIN64A","cl:-W3 -Gs0 -Gy -Zi -nologo -DOPENSSL_SYSNAME_WIN32 -DWIN32_LEAN_AND_MEAN -DL_ENDIAN -DUNICODE -D_UNICODE -D_CRT_SECURE_NO_DEPRECATE:::WIN64A::SIXTY_FOUR_BIT RC4_CHUNK_LL DES_INT EXPORT_VAR_AS_FN:".eval{my $asm=$x86_64_asm;$asm=~s/x86_64-gcc\.o/bn_asm.o/;$asm}.":auto:win32", # x86 Win32 target defaults to ANSI API, if you want UNICODE, complement # 'perl Configure VC-WIN32' with '-DUNICODE -D_UNICODE' "VC-WIN32","cl:-W3 -Gs0 -GF -Gy -nologo -DOPENSSL_SYSNAME_WIN32 -DWIN32_LEAN_AND_MEAN -DL_ENDIAN -D_CRT_SECURE_NO_DEPRECATE:::WIN32::BN_LLONG RC4_INDEX EXPORT_VAR_AS_FN ${x86_gcc_opts}:${x86_asm}:win32n:win32", @@ -1510,6 +1510,7 @@ $cflags.=" -DOPENSSL_BN_ASM_PART_WORDS" if ($bn_obj =~ /bn-586/); $cflags.=" -DOPENSSL_IA32_SSE2" if (!$no_sse2 && $bn_obj =~ /86/); $cflags.=" -DOPENSSL_BN_ASM_MONT" if ($bn_obj =~ /-mont/); +$cflags.=" -DOPENSSL_BN_ASM_MONT5" if ($bn_obj =~ /-mont5/); $cflags.=" -DOPENSSL_BN_ASM_GF2m" if ($bn_obj =~ /-gf2m/); if ($fips) diff --git a/TABLE b/TABLE index f520d7116b..b5aea36d97 100644 --- a/TABLE +++ b/TABLE @@ -297,7 +297,7 @@ $sys_id = $lflags = $bn_ops = SIXTY_FOUR_BIT_LONG RC4_CHUNK DES_INT DES_UNROLL $cpuid_obj = x86_64cpuid.o -$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-gf2m.o modexp512-x86_64.o +$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-mont5.o x86_64-gf2m.o modexp512-x86_64.o $des_obj = $aes_obj = aes-x86_64.o aesni-x86_64.o $bf_obj = @@ -777,7 +777,7 @@ $sys_id = WIN64A $lflags = $bn_ops = SIXTY_FOUR_BIT RC4_CHUNK_LL DES_INT EXPORT_VAR_AS_FN $cpuid_obj = x86_64cpuid.o -$bn_obj = bn_asm.o x86_64-mont.o +$bn_obj = bn_asm.o x86_64-mont.o x86_64-mont5.o x86_64-gf2m.o modexp512-x86_64.o $des_obj = $aes_obj = aes-x86_64.o aesni-x86_64.o $bf_obj = @@ -1385,7 +1385,7 @@ $sys_id = MACOSX $lflags = -Wl,-search_paths_first% $bn_ops = SIXTY_FOUR_BIT_LONG RC4_CHAR RC4_CHUNK DES_INT DES_UNROLL $cpuid_obj = x86_64cpuid.o -$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-gf2m.o modexp512-x86_64.o +$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-mont5.o x86_64-gf2m.o modexp512-x86_64.o $des_obj = $aes_obj = aes-x86_64.o aesni-x86_64.o $bf_obj = @@ -1545,9 +1545,9 @@ $sys_id = WIN64A $lflags = $bn_ops = SIXTY_FOUR_BIT RC4_CHUNK_LL DES_INT EXPORT_VAR_AS_FN $cpuid_obj = x86_64cpuid.o -$bn_obj = bn_asm.o x86_64-mont.o +$bn_obj = bn_asm.o x86_64-mont.o x86_64-mont5.o x86_64-gf2m.o modexp512-x86_64.o $des_obj = -$aes_obj = aes-x86_64.o +$aes_obj = aes-x86_64.o aesni-x86_64.o $bf_obj = $md5_obj = md5-x86_64.o $sha1_obj = sha1-x86_64.o sha256-x86_64.o sha512-x86_64.o @@ -2313,7 +2313,7 @@ $sys_id = $lflags = -ldl $bn_ops = SIXTY_FOUR_BIT_LONG RC4_CHUNK DES_INT DES_UNROLL $cpuid_obj = x86_64cpuid.o -$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-gf2m.o modexp512-x86_64.o +$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-mont5.o x86_64-gf2m.o modexp512-x86_64.o $des_obj = $aes_obj = aes-x86_64.o aesni-x86_64.o $bf_obj = @@ -2505,7 +2505,7 @@ $sys_id = $lflags = -ldl $bn_ops = SIXTY_FOUR_BIT_LONG RC4_CHUNK DES_INT DES_UNROLL $cpuid_obj = x86_64cpuid.o -$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-gf2m.o modexp512-x86_64.o +$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-mont5.o x86_64-gf2m.o modexp512-x86_64.o $des_obj = $aes_obj = aes-x86_64.o aesni-x86_64.o $bf_obj = @@ -2569,7 +2569,7 @@ $sys_id = $lflags = -ldl $bn_ops = SIXTY_FOUR_BIT_LONG RC4_CHUNK DES_INT DES_UNROLL $cpuid_obj = x86_64cpuid.o -$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-gf2m.o modexp512-x86_64.o +$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-mont5.o x86_64-gf2m.o modexp512-x86_64.o $des_obj = $aes_obj = aes-x86_64.o aesni-x86_64.o $bf_obj = @@ -4073,7 +4073,7 @@ $sys_id = $lflags = -ldl $bn_ops = SIXTY_FOUR_BIT_LONG RC4_CHUNK DES_INT DES_UNROLL $cpuid_obj = x86_64cpuid.o -$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-gf2m.o modexp512-x86_64.o +$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-mont5.o x86_64-gf2m.o modexp512-x86_64.o $des_obj = $aes_obj = aes-x86_64.o aesni-x86_64.o $bf_obj = @@ -4233,7 +4233,7 @@ $sys_id = MINGW64 $lflags = -lws2_32 -lgdi32 -lcrypt32 $bn_ops = SIXTY_FOUR_BIT RC4_CHUNK_LL DES_INT EXPORT_VAR_AS_FN $cpuid_obj = x86_64cpuid.o -$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-gf2m.o modexp512-x86_64.o +$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-mont5.o x86_64-gf2m.o modexp512-x86_64.o $des_obj = $aes_obj = aes-x86_64.o aesni-x86_64.o $bf_obj = @@ -5193,7 +5193,7 @@ $sys_id = $lflags = -lsocket -lnsl -ldl $bn_ops = SIXTY_FOUR_BIT_LONG RC4_CHUNK DES_INT DES_UNROLL $cpuid_obj = x86_64cpuid.o -$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-gf2m.o modexp512-x86_64.o +$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-mont5.o x86_64-gf2m.o modexp512-x86_64.o $des_obj = $aes_obj = aes-x86_64.o aesni-x86_64.o $bf_obj = @@ -5225,7 +5225,7 @@ $sys_id = $lflags = -lsocket -lnsl -ldl $bn_ops = SIXTY_FOUR_BIT_LONG RC4_CHUNK DES_INT DES_UNROLL $cpuid_obj = x86_64cpuid.o -$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-gf2m.o modexp512-x86_64.o +$bn_obj = x86_64-gcc.o x86_64-mont.o x86_64-mont5.o x86_64-gf2m.o modexp512-x86_64.o $des_obj = $aes_obj = aes-x86_64.o aesni-x86_64.o $bf_obj = diff --git a/crypto/bn/Makefile b/crypto/bn/Makefile index 4ae6af5060..1fd8e33371 100644 --- a/crypto/bn/Makefile +++ b/crypto/bn/Makefile @@ -98,6 +98,8 @@ x86_64-gcc.o: asm/x86_64-gcc.c $(CC) $(CFLAGS) -c -o $@ asm/x86_64-gcc.c x86_64-mont.s: asm/x86_64-mont.pl $(PERL) asm/x86_64-mont.pl $(PERLASM_SCHEME) > $@ +x86_64-mont5.s: asm/x86_64-mont5.pl + $(PERL) asm/x86_64-mont5.pl $(PERLASM_SCHEME) > $@ x86_64-gf2m.s: asm/x86_64-gf2m.pl $(PERL) asm/x86_64-gf2m.pl $(PERLASM_SCHEME) > $@ modexp512-x86_64.s: asm/modexp512-x86_64.pl diff --git a/crypto/bn/asm/x86_64-mont.pl b/crypto/bn/asm/x86_64-mont.pl index 4f330b81f3..c2a308ddfa 100755 --- a/crypto/bn/asm/x86_64-mont.pl +++ b/crypto/bn/asm/x86_64-mont.pl @@ -1,7 +1,7 @@ #!/usr/bin/env perl # ==================================================================== -# Written by Andy Polyakov for the OpenSSL +# Written by Andy Polyakov 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/. @@ -142,6 +142,7 @@ $code.=<<___; jne .L1st add %rax,$hi1 + mov ($ap),%rax # ap[0] adc \$0,%rdx add $hi0,$hi1 # np[j]*m1+ap[j]*bp[0] adc \$0,%rdx @@ -161,7 +162,6 @@ $code.=<<___; .Louter: mov ($bp,$i,8),$m0 # m0=bp[i] xor $j,$j # j=0 - mov ($ap),%rax # ap[0] mov $n0,$m1 mov (%rsp),$lo0 mulq $m0 # ap[0]*bp[i] @@ -208,6 +208,7 @@ $code.=<<___; jne .Linner add %rax,$hi1 + mov ($ap),%rax # ap[0] adc \$0,%rdx add $lo0,$hi1 # np[j]*m1+ap[j]*bp[i]+tp[j] mov (%rsp,$j,8),$lo0 diff --git a/crypto/bn/asm/x86_64-mont5.pl b/crypto/bn/asm/x86_64-mont5.pl new file mode 100755 index 0000000000..b7b1ef6161 --- /dev/null +++ b/crypto/bn/asm/x86_64-mont5.pl @@ -0,0 +1,834 @@ +#!/usr/bin/env perl + +# ==================================================================== +# Written by Andy Polyakov 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/. +# ==================================================================== + +# August 2011. +# +# Companion to x86_64-mont.pl that optimizes cache-timing attack +# countermeasures. The subroutines are produced by replacing bp[i] +# references in their x86_64-mont.pl counterparts with cache-neutral +# references to powers table computed in BN_mod_exp_mont_consttime. +# In addition subroutine that scatters elements of the powers table +# is implemented, so that scatter-/gathering can be tuned without +# bn_exp.c modifications. + +$flavour = shift; +$output = shift; +if ($flavour =~ /\./) { $output = $flavour; undef $flavour; } + +$win64=0; $win64=1 if ($flavour =~ /[nm]asm|mingw64/ || $output =~ /\.asm$/); + +$0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1; +( $xlate="${dir}x86_64-xlate.pl" and -f $xlate ) or +( $xlate="${dir}../../perlasm/x86_64-xlate.pl" and -f $xlate) or +die "can't locate x86_64-xlate.pl"; + +open STDOUT,"| $^X $xlate $flavour $output"; + +# int bn_mul_mont_gather5( +$rp="%rdi"; # BN_ULONG *rp, +$ap="%rsi"; # const BN_ULONG *ap, +$bp="%rdx"; # const BN_ULONG *bp, +$np="%rcx"; # const BN_ULONG *np, +$n0="%r8"; # const BN_ULONG *n0, +$num="%r9"; # int num, + # int idx); # 0 to 2^5-1, "index" in $bp holding + # pre-computed powers of a', interlaced + # in such manner that b[0] is $bp[idx], + # b[1] is [2^5+idx], etc. +$lo0="%r10"; +$hi0="%r11"; +$hi1="%r13"; +$i="%r14"; +$j="%r15"; +$m0="%rbx"; +$m1="%rbp"; + +$code=<<___; +.text + +.globl bn_mul_mont_gather5 +.type bn_mul_mont_gather5,\@function,6 +.align 64 +bn_mul_mont_gather5: + test \$3,${num}d + jnz .Lmul_enter + cmp \$8,${num}d + jb .Lmul_enter + jmp .Lmul4x_enter + +.align 16 +.Lmul_enter: + mov `($win64?56:8)`(%rsp),%r10d # load 7th argument + push %rbx + push %rbp + push %r12 + push %r13 + push %r14 + push %r15 + + mov ${num}d,${num}d + lea 2($num),%r11 + mov %rsp,%rax + neg %r11 + lea (%rsp,%r11,8),%rsp # tp=alloca(8*(num+2)) + and \$-1024,%rsp # minimize TLB usage + + mov %rax,8(%rsp,$num,8) # tp[num+1]=%rsp +.Lmul_body: + mov $bp,%r12 # reassign $bp +___ + $bp="%r12"; + $STRIDE=2**5*8; # 5 is "window size" + $N=$STRIDE/4; # should match cache line size +$code.=<<___; + mov %r10,%r11 + shr \$`log($N/8)/log(2)`,%r10 + and \$`$N/8-1`,%r11 + not %r10 + lea .Lmagic_masks(%rip),%rax + and \$`2**5/($N/8)-1`,%r10 # 5 is "window size" + lea 96($bp,%r11,8),$bp # pointer within 1st cache line + movq 0(%rax,%r10,8),%xmm4 # set of masks denoting which + movq 8(%rax,%r10,8),%xmm5 # cache line contains element + movq 16(%rax,%r10,8),%xmm6 # denoted by 7th argument + movq 24(%rax,%r10,8),%xmm7 + + movq `0*$STRIDE/4-96`($bp),%xmm0 + movq `1*$STRIDE/4-96`($bp),%xmm1 + pand %xmm4,%xmm0 + movq `2*$STRIDE/4-96`($bp),%xmm2 + pand %xmm5,%xmm1 + movq `3*$STRIDE/4-96`($bp),%xmm3 + pand %xmm6,%xmm2 + por %xmm1,%xmm0 + pand %xmm7,%xmm3 + por %xmm2,%xmm0 + lea $STRIDE($bp),$bp + por %xmm3,%xmm0 + + movq %xmm0,$m0 # m0=bp[0] + + mov ($n0),$n0 # pull n0[0] value + mov ($ap),%rax + + xor $i,$i # i=0 + xor $j,$j # j=0 + + movq `0*$STRIDE/4-96`($bp),%xmm0 + movq `1*$STRIDE/4-96`($bp),%xmm1 + pand %xmm4,%xmm0 + movq `2*$STRIDE/4-96`($bp),%xmm2 + pand %xmm5,%xmm1 + + mov $n0,$m1 + mulq $m0 # ap[0]*bp[0] + mov %rax,$lo0 + mov ($np),%rax + + movq `3*$STRIDE/4-96`($bp),%xmm3 + pand %xmm6,%xmm2 + por %xmm1,%xmm0 + pand %xmm7,%xmm3 + + imulq $lo0,$m1 # "tp[0]"*n0 + mov %rdx,$hi0 + + por %xmm2,%xmm0 + lea $STRIDE($bp),$bp + por %xmm3,%xmm0 + + mulq $m1 # np[0]*m1 + add %rax,$lo0 # discarded + mov 8($ap),%rax + adc \$0,%rdx + mov %rdx,$hi1 + + lea 1($j),$j # j++ + jmp .L1st_enter + +.align 16 +.L1st: + add %rax,$hi1 + mov ($ap,$j,8),%rax + adc \$0,%rdx + add $hi0,$hi1 # np[j]*m1+ap[j]*bp[0] + mov $lo0,$hi0 + adc \$0,%rdx + mov $hi1,-16(%rsp,$j,8) # tp[j-1] + mov %rdx,$hi1 + +.L1st_enter: + mulq $m0 # ap[j]*bp[0] + add %rax,$hi0 + mov ($np,$j,8),%rax + adc \$0,%rdx + lea 1($j),$j # j++ + mov %rdx,$lo0 + + mulq $m1 # np[j]*m1 + cmp $num,$j + jne .L1st + + movq %xmm0,$m0 # bp[1] + + add %rax,$hi1 + mov ($ap),%rax # ap[0] + adc \$0,%rdx + add $hi0,$hi1 # np[j]*m1+ap[j]*bp[0] + adc \$0,%rdx + mov $hi1,-16(%rsp,$j,8) # tp[j-1] + mov %rdx,$hi1 + mov $lo0,$hi0 + + xor %rdx,%rdx + add $hi0,$hi1 + adc \$0,%rdx + mov $hi1,-8(%rsp,$num,8) + mov %rdx,(%rsp,$num,8) # store upmost overflow bit + + lea 1($i),$i # i++ + jmp .Louter +.align 16 +.Louter: + xor $j,$j # j=0 + mov $n0,$m1 + mov (%rsp),$lo0 + + movq `0*$STRIDE/4-96`($bp),%xmm0 + movq `1*$STRIDE/4-96`($bp),%xmm1 + pand %xmm4,%xmm0 + movq `2*$STRIDE/4-96`($bp),%xmm2 + pand %xmm5,%xmm1 + + mulq $m0 # ap[0]*bp[i] + add %rax,$lo0 # ap[0]*bp[i]+tp[0] + mov ($np),%rax + adc \$0,%rdx + + movq `3*$STRIDE/4-96`($bp),%xmm3 + pand %xmm6,%xmm2 + por %xmm1,%xmm0 + pand %xmm7,%xmm3 + + imulq $lo0,$m1 # tp[0]*n0 + mov %rdx,$hi0 + + por %xmm2,%xmm0 + lea $STRIDE($bp),$bp + por %xmm3,%xmm0 + + mulq $m1 # np[0]*m1 + add %rax,$lo0 # discarded + mov 8($ap),%rax + adc \$0,%rdx + mov 8(%rsp),$lo0 # tp[1] + mov %rdx,$hi1 + + lea 1($j),$j # j++ + jmp .Linner_enter + +.align 16 +.Linner: + add %rax,$hi1 + mov ($ap,$j,8),%rax + adc \$0,%rdx + add $lo0,$hi1 # np[j]*m1+ap[j]*bp[i]+tp[j] + mov (%rsp,$j,8),$lo0 + adc \$0,%rdx + mov $hi1,-16(%rsp,$j,8) # tp[j-1] + mov %rdx,$hi1 + +.Linner_enter: + mulq $m0 # ap[j]*bp[i] + add %rax,$hi0 + mov ($np,$j,8),%rax + adc \$0,%rdx + add $hi0,$lo0 # ap[j]*bp[i]+tp[j] + mov %rdx,$hi0 + adc \$0,$hi0 + lea 1($j),$j # j++ + + mulq $m1 # np[j]*m1 + cmp $num,$j + jne .Linner + + movq %xmm0,$m0 # bp[i+1] + + add %rax,$hi1 + mov ($ap),%rax # ap[0] + adc \$0,%rdx + add $lo0,$hi1 # np[j]*m1+ap[j]*bp[i]+tp[j] + mov (%rsp,$j,8),$lo0 + adc \$0,%rdx + mov $hi1,-16(%rsp,$j,8) # tp[j-1] + mov %rdx,$hi1 + + xor %rdx,%rdx + add $hi0,$hi1 + adc \$0,%rdx + add $lo0,$hi1 # pull upmost overflow bit + adc \$0,%rdx + mov $hi1,-8(%rsp,$num,8) + mov %rdx,(%rsp,$num,8) # store upmost overflow bit + + lea 1($i),$i # i++ + cmp $num,$i + jl .Louter + + xor $i,$i # i=0 and clear CF! + mov (%rsp),%rax # tp[0] + lea (%rsp),$ap # borrow ap for tp + mov $num,$j # j=num + jmp .Lsub +.align 16 +.Lsub: sbb ($np,$i,8),%rax + mov %rax,($rp,$i,8) # rp[i]=tp[i]-np[i] + mov 8($ap,$i,8),%rax # tp[i+1] + lea 1($i),$i # i++ + dec $j # doesnn't affect CF! + jnz .Lsub + + sbb \$0,%rax # handle upmost overflow bit + xor $i,$i + and %rax,$ap + not %rax + mov $rp,$np + and %rax,$np + mov $num,$j # j=num + or $np,$ap # ap=borrow?tp:rp +.align 16 +.Lcopy: # copy or in-place refresh + mov ($ap,$i,8),%rax + mov $i,(%rsp,$i,8) # zap temporary vector + mov %rax,($rp,$i,8) # rp[i]=tp[i] + lea 1($i),$i + sub \$1,$j + jnz .Lcopy + + mov 8(%rsp,$num,8),%rsi # restore %rsp + mov \$1,%rax + mov (%rsi),%r15 + mov 8(%rsi),%r14 + mov 16(%rsi),%r13 + mov 24(%rsi),%r12 + mov 32(%rsi),%rbp + mov 40(%rsi),%rbx + lea 48(%rsi),%rsp +.Lmul_epilogue: + ret +.size bn_mul_mont_gather5,.-bn_mul_mont_gather5 +___ +{{{ +my @A=("%r10","%r11"); +my @N=("%r13","%rdi"); +$code.=<<___; +.type bn_mul4x_mont_gather5,\@function,6 +.align 16 +bn_mul4x_mont_gather5: +.Lmul4x_enter: + mov `($win64?56:8)`(%rsp),%r10d # load 7th argument + push %rbx + push %rbp + push %r12 + push %r13 + push %r14 + push %r15 + + mov ${num}d,${num}d + lea 4($num),%r11 + mov %rsp,%rax # !!!! + neg %r11 + lea (%rsp,%r11,8),%rsp # tp=alloca(8*(num+4)) + and \$-1024,%rsp # minimize TLB usage + + mov %rax,8(%rsp,$num,8) # tp[num+1]=%rsp +.Lmul4x_body: + mov $rp,16(%rsp,$num,8) # tp[num+2]=$rp + mov %rdx,%r12 # reassign $bp +___ + $bp="%r12"; + $STRIDE=2**5*8; # 5 is "window size" + $N=$STRIDE/4; # should match cache line size +$code.=<<___; + mov %r10,%r11 + shr \$`log($N/8)/log(2)`,%r10 + and \$`$N/8-1`,%r11 + not %r10 + lea .Lmagic_masks(%rip),%rax + and \$`2**5/($N/8)-1`,%r10 # 5 is "window size" + lea 96($bp,%r11,8),$bp # pointer within 1st cache line + movq 0(%rax,%r10,8),%xmm4 # set of masks denoting which + movq 8(%rax,%r10,8),%xmm5 # cache line contains element + movq 16(%rax,%r10,8),%xmm6 # denoted by 7th argument + movq 24(%rax,%r10,8),%xmm7 + + movq `0*$STRIDE/4-96`($bp),%xmm0 + movq `1*$STRIDE/4-96`($bp),%xmm1 + pand %xmm4,%xmm0 + movq `2*$STRIDE/4-96`($bp),%xmm2 + pand %xmm5,%xmm1 + movq `3*$STRIDE/4-96`($bp),%xmm3 + pand %xmm6,%xmm2 + por %xmm1,%xmm0 + pand %xmm7,%xmm3 + por %xmm2,%xmm0 + lea $STRIDE($bp),$bp + por %xmm3,%xmm0 + + movq %xmm0,$m0 # m0=bp[0] + mov ($n0),$n0 # pull n0[0] value + mov ($ap),%rax + + xor $i,$i # i=0 + xor $j,$j # j=0 + + movq `0*$STRIDE/4-96`($bp),%xmm0 + movq `1*$STRIDE/4-96`($bp),%xmm1 + pand %xmm4,%xmm0 + movq `2*$STRIDE/4-96`($bp),%xmm2 + pand %xmm5,%xmm1 + + mov $n0,$m1 + mulq $m0 # ap[0]*bp[0] + mov %rax,$A[0] + mov ($np),%rax + + movq `3*$STRIDE/4-96`($bp),%xmm3 + pand %xmm6,%xmm2 + por %xmm1,%xmm0 + pand %xmm7,%xmm3 + + imulq $A[0],$m1 # "tp[0]"*n0 + mov %rdx,$A[1] + + por %xmm2,%xmm0 + lea $STRIDE($bp),$bp + por %xmm3,%xmm0 + + mulq $m1 # np[0]*m1 + add %rax,$A[0] # discarded + mov 8($ap),%rax + adc \$0,%rdx + mov %rdx,$N[1] + + mulq $m0 + add %rax,$A[1] + mov 8($np),%rax + adc \$0,%rdx + mov %rdx,$A[0] + + mulq $m1 + add %rax,$N[1] + mov 16($ap),%rax + adc \$0,%rdx + add $A[1],$N[1] + lea 4($j),$j # j++ + adc \$0,%rdx + mov $N[1],(%rsp) + mov %rdx,$N[0] + jmp .L1st4x +.align 16 +.L1st4x: + mulq $m0 # ap[j]*bp[0] + add %rax,$A[0] + mov -16($np,$j,8),%rax + adc \$0,%rdx + mov %rdx,$A[1] + + mulq $m1 # np[j]*m1 + add %rax,$N[0] + mov -8($ap,$j,8),%rax + adc \$0,%rdx + add $A[0],$N[0] # np[j]*m1+ap[j]*bp[0] + adc \$0,%rdx + mov $N[0],-24(%rsp,$j,8) # tp[j-1] + mov %rdx,$N[1] + + mulq $m0 # ap[j]*bp[0] + add %rax,$A[1] + mov -8($np,$j,8),%rax + adc \$0,%rdx + mov %rdx,$A[0] + + mulq $m1 # np[j]*m1 + add %rax,$N[1] + mov ($ap,$j,8),%rax + adc \$0,%rdx + add $A[1],$N[1] # np[j]*m1+ap[j]*bp[0] + adc \$0,%rdx + mov $N[1],-16(%rsp,$j,8) # tp[j-1] + mov %rdx,$N[0] + + mulq $m0 # ap[j]*bp[0] + add %rax,$A[0] + mov ($np,$j,8),%rax + adc \$0,%rdx + mov %rdx,$A[1] + + mulq $m1 # np[j]*m1 + add %rax,$N[0] + mov 8($ap,$j,8),%rax + adc \$0,%rdx + add $A[0],$N[0] # np[j]*m1+ap[j]*bp[0] + adc \$0,%rdx + mov $N[0],-8(%rsp,$j,8) # tp[j-1] + mov %rdx,$N[1] + + mulq $m0 # ap[j]*bp[0] + add %rax,$A[1] + mov 8($np,$j,8),%rax + adc \$0,%rdx + lea 4($j),$j # j++ + mov %rdx,$A[0] + + mulq $m1 # np[j]*m1 + add %rax,$N[1] + mov -16($ap,$j,8),%rax + adc \$0,%rdx + add $A[1],$N[1] # np[j]*m1+ap[j]*bp[0] + adc \$0,%rdx + mov $N[1],-32(%rsp,$j,8) # tp[j-1] + mov %rdx,$N[0] + cmp $num,$j + jl .L1st4x + + mulq $m0 # ap[j]*bp[0] + add %rax,$A[0] + mov -16($np,$j,8),%rax + adc \$0,%rdx + mov %rdx,$A[1] + + mulq $m1 # np[j]*m1 + add %rax,$N[0] + mov -8($ap,$j,8),%rax + adc \$0,%rdx + add $A[0],$N[0] # np[j]*m1+ap[j]*bp[0] + adc \$0,%rdx + mov $N[0],-24(%rsp,$j,8) # tp[j-1] + mov %rdx,$N[1] + + mulq $m0 # ap[j]*bp[0] + add %rax,$A[1] + mov -8($np,$j,8),%rax + adc \$0,%rdx + mov %rdx,$A[0] + + mulq $m1 # np[j]*m1 + add %rax,$N[1] + mov ($ap),%rax # ap[0] + adc \$0,%rdx + add $A[1],$N[1] # np[j]*m1+ap[j]*bp[0] + adc \$0,%rdx + mov $N[1],-16(%rsp,$j,8) # tp[j-1] + mov %rdx,$N[0] + + movq %xmm0,$m0 # bp[1] + + xor $N[1],$N[1] + add $A[0],$N[0] + adc \$0,$N[1] + mov $N[0],-8(%rsp,$j,8) + mov $N[1],(%rsp,$j,8) # store upmost overflow bit + + lea 1($i),$i # i++ +.align 4 +.Louter4x: + xor $j,$j # j=0 + movq `0*$STRIDE/4-96`($bp),%xmm0 + movq `1*$STRIDE/4-96`($bp),%xmm1 + pand %xmm4,%xmm0 + movq `2*$STRIDE/4-96`($bp),%xmm2 + pand %xmm5,%xmm1 + + mov (%rsp),$A[0] + mov $n0,$m1 + mulq $m0 # ap[0]*bp[i] + add %rax,$A[0] # ap[0]*bp[i]+tp[0] + mov ($np),%rax + adc \$0,%rdx + + movq `3*$STRIDE/4-96`($bp),%xmm3 + pand %xmm6,%xmm2 + por %xmm1,%xmm0 + pand %xmm7,%xmm3 + + imulq $A[0],$m1 # tp[0]*n0 + mov %rdx,$A[1] + + por %xmm2,%xmm0 + lea $STRIDE($bp),$bp + por %xmm3,%xmm0 + + mulq $m1 # np[0]*m1 + add %rax,$A[0] # "$N[0]", discarded + mov 8($ap),%rax + adc \$0,%rdx + mov %rdx,$N[1] + + mulq $m0 # ap[j]*bp[i] + add %rax,$A[1] + mov 8($np),%rax + adc \$0,%rdx + add 8(%rsp),$A[1] # +tp[1] + adc \$0,%rdx + mov %rdx,$A[0] + + mulq $m1 # np[j]*m1 + add %rax,$N[1] + mov 16($ap),%rax + adc \$0,%rdx + add $A[1],$N[1] # np[j]*m1+ap[j]*bp[i]+tp[j] + lea 4($j),$j # j+=2 + adc \$0,%rdx + mov $N[1],(%rsp) # tp[j-1] + mov %rdx,$N[0] + jmp .Linner4x +.align 16 +.Linner4x: + mulq $m0 # ap[j]*bp[i] + add %rax,$A[0] + mov -16($np,$j,8),%rax + adc \$0,%rdx + add -16(%rsp,$j,8),$A[0] # ap[j]*bp[i]+tp[j] + adc \$0,%rdx + mov %rdx,$A[1] + + mulq $m1 # np[j]*m1 + add %rax,$N[0] + mov -8($ap,$j,8),%rax + adc \$0,%rdx + add $A[0],$N[0] + adc \$0,%rdx + mov $N[0],-24(%rsp,$j,8) # tp[j-1] + mov %rdx,$N[1] + + mulq $m0 # ap[j]*bp[i] + add %rax,$A[1] + mov -8($np,$j,8),%rax + adc \$0,%rdx + add -8(%rsp,$j,8),$A[1] + adc \$0,%rdx + mov %rdx,$A[0] + + mulq $m1 # np[j]*m1 + add %rax,$N[1] + mov ($ap,$j,8),%rax + adc \$0,%rdx + add $A[1],$N[1] + adc \$0,%rdx + mov $N[1],-16(%rsp,$j,8) # tp[j-1] + mov %rdx,$N[0] + + mulq $m0 # ap[j]*bp[i] + add %rax,$A[0] + mov ($np,$j,8),%rax + adc \$0,%rdx + add (%rsp,$j,8),$A[0] # ap[j]*bp[i]+tp[j] + adc \$0,%rdx + mov %rdx,$A[1] + + mulq $m1 # np[j]*m1 + add %rax,$N[0] + mov 8($ap,$j,8),%rax + adc \$0,%rdx + add $A[0],$N[0] + adc \$0,%rdx + mov $N[0],-8(%rsp,$j,8) # tp[j-1] + mov %rdx,$N[1] + + mulq $m0 # ap[j]*bp[i] + add %rax,$A[1] + mov 8($np,$j,8),%rax + adc \$0,%rdx + add 8(%rsp,$j,8),$A[1] + adc \$0,%rdx + lea 4($j),$j # j++ + mov %rdx,$A[0] + + mulq $m1 # np[j]*m1 + add %rax,$N[1] + mov -16($ap,$j,8),%rax + adc \$0,%rdx + add $A[1],$N[1] + adc \$0,%rdx + mov $N[1],-32(%rsp,$j,8) # tp[j-1] + mov %rdx,$N[0] + cmp $num,$j + jl .Linner4x + + mulq $m0 # ap[j]*bp[i] + add %rax,$A[0] + mov -16($np,$j,8),%rax + adc \$0,%rdx + add -16(%rsp,$j,8),$A[0] # ap[j]*bp[i]+tp[j] + adc \$0,%rdx + mov %rdx,$A[1] + + mulq $m1 # np[j]*m1 + add %rax,$N[0] + mov -8($ap,$j,8),%rax + adc \$0,%rdx + add $A[0],$N[0] + adc \$0,%rdx + mov $N[0],-24(%rsp,$j,8) # tp[j-1] + mov %rdx,$N[1] + + mulq $m0 # ap[j]*bp[i] + add %rax,$A[1] + mov -8($np,$j,8),%rax + adc \$0,%rdx + add -8(%rsp,$j,8),$A[1] + adc \$0,%rdx + lea 1($i),$i # i++ + mov %rdx,$A[0] + + mulq $m1 # np[j]*m1 + add %rax,$N[1] + mov ($ap),%rax # ap[0] + adc \$0,%rdx + add $A[1],$N[1] + adc \$0,%rdx + mov $N[1],-16(%rsp,$j,8) # tp[j-1] + mov %rdx,$N[0] + + movq %xmm0,$m0 # bp[i+1] + + xor $N[1],$N[1] + add $A[0],$N[0] + adc \$0,$N[1] + add (%rsp,$num,8),$N[0] # pull upmost overflow bit + adc \$0,$N[1] + mov $N[0],-8(%rsp,$j,8) + mov $N[1],(%rsp,$j,8) # store upmost overflow bit + + cmp $num,$i + jl .Louter4x +___ +{ +my @ri=("%rax","%rdx",$m0,$m1); +$code.=<<___; + mov 16(%rsp,$num,8),$rp # restore $rp + mov 0(%rsp),@ri[0] # tp[0] + pxor %xmm0,%xmm0 + mov 8(%rsp),@ri[1] # tp[1] + shr \$2,$num # num/=4 + lea (%rsp),$ap # borrow ap for tp + xor $i,$i # i=0 and clear CF! + + sub 0($np),@ri[0] + mov 16($ap),@ri[2] # tp[2] + mov 24($ap),@ri[3] # tp[3] + sbb 8($np),@ri[1] + lea -1($num),$j # j=num/4-1 + jmp .Lsub4x +.align 16 +.Lsub4x: + mov @ri[0],0($rp,$i,8) # rp[i]=tp[i]-np[i] + mov @ri[1],8($rp,$i,8) # rp[i]=tp[i]-np[i] + sbb 16($np,$i,8),@ri[2] + mov 32($ap,$i,8),@ri[0] # tp[i+1] + mov 40($ap,$i,8),@ri[1] + sbb 24($np,$i,8),@ri[3] + mov @ri[2],16($rp,$i,8) # rp[i]=tp[i]-np[i] + mov @ri[3],24($rp,$i,8) # rp[i]=tp[i]-np[i] + sbb 32($np,$i,8),@ri[0] + mov 48($ap,$i,8),@ri[2] + mov 56($ap,$i,8),@ri[3] + sbb 40($np,$i,8),@ri[1] + lea 4($i),$i # i++ + dec $j # doesnn't affect CF! + jnz .Lsub4x + + mov @ri[0],0($rp,$i,8) # rp[i]=tp[i]-np[i] + mov 32($ap,$i,8),@ri[0] # load overflow bit + sbb 16($np,$i,8),@ri[2] + mov @ri[1],8($rp,$i,8) # rp[i]=tp[i]-np[i] + sbb 24($np,$i,8),@ri[3] + mov @ri[2],16($rp,$i,8) # rp[i]=tp[i]-np[i] + + sbb \$0,@ri[0] # handle upmost overflow bit + mov @ri[3],24($rp,$i,8) # rp[i]=tp[i]-np[i] + xor $i,$i # i=0 + and @ri[0],$ap + not @ri[0] + mov $rp,$np + and @ri[0],$np + lea -1($num),$j + or $np,$ap # ap=borrow?tp:rp + + movdqu ($ap),%xmm1 + movdqa %xmm0,(%rsp) + movdqu %xmm1,($rp) + jmp .Lcopy4x +.align 16 +.Lcopy4x: # copy or in-place refresh + movdqu 16($ap,$i),%xmm2 + movdqu 32($ap,$i),%xmm1 + movdqa %xmm0,16(%rsp,$i) + movdqu %xmm2,16($rp,$i) + movdqa %xmm0,32(%rsp,$i) + movdqu %xmm1,32($rp,$i) + lea 32($i),$i + dec $j + jnz .Lcopy4x + + shl \$2,$num + movdqu 16($ap,$i),%xmm2 + movdqa %xmm0,16(%rsp,$i) + movdqu %xmm2,16($rp,$i) +___ +} +$code.=<<___; + mov 8(%rsp,$num,8),%rsi # restore %rsp + mov \$1,%rax + mov (%rsi),%r15 + mov 8(%rsi),%r14 + mov 16(%rsi),%r13 + mov 24(%rsi),%r12 + mov 32(%rsi),%rbp + mov 40(%rsi),%rbx + lea 48(%rsi),%rsp +.Lmul4x_epilogue: + ret +.size bn_mul4x_mont_gather5,.-bn_mul4x_mont_gather5 +___ +}}} + +{ +my ($inp,$num,$tbl,$idx)=$win64?("%rcx","%rdx","%r8", "%r9") : # Win64 order + ("%rdi","%rsi","%rdx","%rcx"); # Unix order +$code.=<<___; +.globl bn_scatter5 +.type bn_scatter5,\@abi-omnipotent +.align 16 +bn_scatter5: + lea ($tbl,$idx,8),$tbl +.Lscatter: + mov ($inp),%rax + lea 8($inp),$inp + mov %rax,($tbl) + lea 32*8($tbl),$tbl + sub \$1,$num + jnz .Lscatter + ret +.size bn_scatter5,.-bn_scatter5 +___ +} +$code.=<<___; +.align 64 +.Lmagic_masks: + .long 0,0, 0,0, 0,0, -1,-1 + .long 0,0, 0,0, 0,0, 0,0 +.asciz "Montgomery Multiplication with scatter/gather for x86_64, CRYPTOGAMS by " +___ + +$code =~ s/\`([^\`]*)\`/eval($1)/gem; + +print $code; +close STDOUT; diff --git a/crypto/bn/bn_exp.c b/crypto/bn/bn_exp.c index ce31ad0a58..5b00aa1e3c 100644 --- a/crypto/bn/bn_exp.c +++ b/crypto/bn/bn_exp.c @@ -114,6 +114,18 @@ #include "cryptlib.h" #include "bn_lcl.h" +#include +#ifdef _WIN32 +# include +# ifndef alloca +# define alloca _alloca +# endif +#elif defined(__GNUC__) +# ifndef alloca +# define alloca(s) __builtin_alloca((s)) +# endif +#endif + /* maximum precomputation table size for *variable* sliding windows */ #define TABLE_SIZE 32 @@ -562,7 +574,7 @@ static int MOD_EXP_CTIME_COPY_FROM_PREBUF(BIGNUM *b, int top, unsigned char *buf /* Given a pointer value, compute the next address that is a cache line multiple. */ #define MOD_EXP_CTIME_ALIGN(x_) \ - ((unsigned char*)(x_) + (MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH - (((BN_ULONG)(x_)) & (MOD_EXP_CTIME_MIN_CACHE_LINE_MASK)))) + ((unsigned char*)(x_) + (MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH - (((size_t)(x_)) & (MOD_EXP_CTIME_MIN_CACHE_LINE_MASK)))) /* This variant of BN_mod_exp_mont() uses fixed windows and the special * precomputation memory layout to limit data-dependency to a minimum @@ -573,17 +585,16 @@ static int MOD_EXP_CTIME_COPY_FROM_PREBUF(BIGNUM *b, int top, unsigned char *buf int BN_mod_exp_mont_consttime(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p, const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont) { - int i,bits,ret=0,idx,window,wvalue; + int i,bits,ret=0,window,wvalue; int top; BIGNUM *r; - const BIGNUM *aa; BN_MONT_CTX *mont=NULL; int numPowers; unsigned char *powerbufFree=NULL; int powerbufLen = 0; unsigned char *powerbuf=NULL; - BIGNUM *computeTemp=NULL, *am=NULL; + BIGNUM computeTemp, *am=NULL; bn_check_top(a); bn_check_top(p); @@ -621,39 +632,149 @@ int BN_mod_exp_mont_consttime(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p, /* Get the window size to use with size of p. */ window = BN_window_bits_for_ctime_exponent_size(bits); +#if defined(OPENSSL_BN_ASM_MONT5) + if (window==6 && bits<=1024) window=5; /* ~5% improvement of 2048-bit RSA sign */ +#endif + /* Adjust the number of bits up to a multiple of the window size. + * If the exponent length is not a multiple of the window size, then + * this pads the most significant bits with zeros to normalize the + * scanning loop to there's no special cases. + * + * * NOTE: Making the window size a power of two less than the native + * * word size ensures that the padded bits won't go past the last + * * word in the internal BIGNUM structure. Going past the end will + * * still produce the correct result, but causes a different branch + * * to be taken in the BN_is_bit_set function. + */ + bits = ((bits+window-1)/window)*window; /* Allocate a buffer large enough to hold all of the pre-computed - * powers of a. + * powers of a, plus computeTemp. */ numPowers = 1 << window; - powerbufLen = sizeof(m->d[0])*top*numPowers; - if ((powerbufFree=(unsigned char*)OPENSSL_malloc(powerbufLen+MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH)) == NULL) + powerbufLen = sizeof(m->d[0])*(top*numPowers + + (top>numPowers?top:numPowers)); + if (powerbufLen < 3072) + powerbufFree = alloca(powerbufLen+MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH); + else if ((powerbufFree=(unsigned char*)OPENSSL_malloc(powerbufLen+MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH)) == NULL) goto err; powerbuf = MOD_EXP_CTIME_ALIGN(powerbufFree); memset(powerbuf, 0, powerbufLen); + if (powerbufLen < 3072) + powerbufFree = NULL; + + computeTemp.d = (BN_ULONG *)(powerbuf + sizeof(m->d[0])*top*numPowers); + computeTemp.top = computeTemp.dmax = top; + computeTemp.neg = 0; + computeTemp.flags = BN_FLG_STATIC_DATA; + /* Initialize the intermediate result. Do this early to save double conversion, * once each for a^0 and intermediate result. */ if (!BN_to_montgomery(r,BN_value_one(),mont,ctx)) goto err; - if (!MOD_EXP_CTIME_COPY_TO_PREBUF(r, top, powerbuf, 0, numPowers)) goto err; /* Initialize computeTemp as a^1 with montgomery precalcs */ - computeTemp = BN_CTX_get(ctx); am = BN_CTX_get(ctx); - if (computeTemp==NULL || am==NULL) goto err; + if (am==NULL) goto err; if (a->neg || BN_ucmp(a,m) >= 0) { - if (!BN_mod(am,a,m,ctx)) - goto err; - aa= am; + if (!BN_mod(am,a,m,ctx)) goto err; + if (!BN_to_montgomery(am,am,mont,ctx)) goto err; } - else - aa=a; - if (!BN_to_montgomery(am,aa,mont,ctx)) goto err; - if (!BN_copy(computeTemp, am)) goto err; + else if (!BN_to_montgomery(am,a,mont,ctx)) goto err; + + if (!BN_copy(&computeTemp, am)) goto err; + + if (bn_wexpand(am,top)==NULL || bn_wexpand(r,top)==NULL) + goto err; + +#if defined(OPENSSL_BN_ASM_MONT5) + /* This optimization uses ideas from http://eprint.iacr.org/2011/239, + * specifically optimization of cache-timing attack countermeasures + * and pre-computation optimization. */ + + /* Dedicated window==4 case improves 512-bit RSA sign by ~15%, but as + * 512-bit RSA is hardly relevant, we omit it to spare size... */ + if (window==5) + { + void bn_mul_mont_gather5(BN_ULONG *rp,const BN_ULONG *ap, + const void *table,const BN_ULONG *np, + const BN_ULONG *n0,int num,int power); + void bn_scatter5(const BN_ULONG *inp,size_t num, + void *table,size_t power); + + BN_ULONG *acc, *np=mont->N.d, *n0=mont->n0; + + bn_scatter5(r->d,r->top,powerbuf,0); + bn_scatter5(am->d,am->top,powerbuf,1); + + acc = computeTemp.d; +#if 0 + for (i=2; i<32; i++) + { + bn_mul_mont_gather5(acc,am->d,powerbuf,np,n0,top,i-1); + bn_scatter5(acc,top,powerbuf,i); + } +#else + /* same as above, but uses squaring for 1/2 of operations */ + for (i=2; i<32; i*=2) + { + bn_mul_mont(acc,acc,acc,np,n0,top); + bn_scatter5(acc,top,powerbuf,i); + } + for (i=3; i<8; i+=2) + { + int j; + bn_mul_mont_gather5(acc,am->d,powerbuf,np,n0,top,i-1); + bn_scatter5(acc,top,powerbuf,i); + for (j=2*i; j<32; j*=2) + { + bn_mul_mont(acc,acc,acc,np,n0,top); + bn_scatter5(acc,top,powerbuf,j); + } + } + for (; i<16; i+=2) + { + bn_mul_mont_gather5(acc,am->d,powerbuf,np,n0,top,i-1); + bn_scatter5(acc,top,powerbuf,i); + bn_mul_mont(acc,acc,acc,np,n0,top); + bn_scatter5(acc,top,powerbuf,2*i); + } + for (; i<32; i+=2) + { + bn_mul_mont_gather5(acc,am->d,powerbuf,np,n0,top,i-1); + bn_scatter5(acc,top,powerbuf,i); + } +#endif + acc = r->d; + + /* Scan the exponent one window at a time starting from the most + * significant bits. + */ + bits--; + while (bits >= 0) + { + for (wvalue=0, i=0; i<5; i++,bits--) + wvalue = (wvalue<<1)+BN_is_bit_set(p,bits); + + bn_mul_mont(acc,acc,acc,np,n0,top); + bn_mul_mont(acc,acc,acc,np,n0,top); + bn_mul_mont(acc,acc,acc,np,n0,top); + bn_mul_mont(acc,acc,acc,np,n0,top); + bn_mul_mont(acc,acc,acc,np,n0,top); + bn_mul_mont_gather5(acc,acc,powerbuf,np,n0,top,wvalue); + } + + r->top=top; + bn_correct_top(r); + } + else +#endif + { + if (!MOD_EXP_CTIME_COPY_TO_PREBUF(r, top, powerbuf, 0, numPowers)) goto err; if (!MOD_EXP_CTIME_COPY_TO_PREBUF(am, top, powerbuf, 1, numPowers)) goto err; /* If the window size is greater than 1, then calculate @@ -666,46 +787,34 @@ int BN_mod_exp_mont_consttime(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p, for (i=2; i= 0) + bits--; + while (bits >= 0) { wvalue=0; /* The 'value' of the window */ /* Scan the window, squaring the result as we go */ - for (i=0; i