Add SHA224 and 256 implementations using Zvknha or Zvknhb vector crypto extensions from OpenSSL(openssl/openssl#21923). Co-developed-by: Charalampos Mitrodimas <charalampos.mitrodimas@xxxxxxxx> Signed-off-by: Charalampos Mitrodimas <charalampos.mitrodimas@xxxxxxxx> Co-developed-by: Heiko Stuebner <heiko.stuebner@xxxxxxxx> Signed-off-by: Heiko Stuebner <heiko.stuebner@xxxxxxxx> Co-developed-by: Phoebe Chen <phoebe.chen@xxxxxxxxxx> Signed-off-by: Phoebe Chen <phoebe.chen@xxxxxxxxxx> Signed-off-by: Jerry Shih <jerry.shih@xxxxxxxxxx> --- Changelog v4: - Use asm mnemonics for the instructions in vector crypto 1.0 extension. Changelog v3: - Use `SYM_TYPED_FUNC_START` for sha256 indirect-call asm symbol. - Use asm mnemonics for the instructions in RVV 1.0 extension. Changelog v2: - Do not turn on kconfig `SHA256_RISCV64` option by default. - Add `asmlinkage` qualifier for crypto asm function. - Rename sha256-riscv64-zvkb-zvknha_or_zvknhb to sha256-riscv64-zvknha_or_zvknhb-zvkb. - Reorder structure sha256_algs members initialization in the order declared. --- arch/riscv/crypto/Kconfig | 11 + arch/riscv/crypto/Makefile | 7 + arch/riscv/crypto/sha256-riscv64-glue.c | 145 ++++++++ .../sha256-riscv64-zvknha_or_zvknhb-zvkb.pl | 317 ++++++++++++++++++ 4 files changed, 480 insertions(+) create mode 100644 arch/riscv/crypto/sha256-riscv64-glue.c create mode 100644 arch/riscv/crypto/sha256-riscv64-zvknha_or_zvknhb-zvkb.pl diff --git a/arch/riscv/crypto/Kconfig b/arch/riscv/crypto/Kconfig index d73b89ceb1a3..ff1dce4a2bcc 100644 --- a/arch/riscv/crypto/Kconfig +++ b/arch/riscv/crypto/Kconfig @@ -44,4 +44,15 @@ config CRYPTO_GHASH_RISCV64 Architecture: riscv64 using: - Zvkg vector crypto extension +config CRYPTO_SHA256_RISCV64 + tristate "Hash functions: SHA-224 and SHA-256" + depends on 64BIT && RISCV_ISA_V && TOOLCHAIN_HAS_VECTOR_CRYPTO + select CRYPTO_SHA256 + help + SHA-224 and SHA-256 secure hash algorithm (FIPS 180) + + Architecture: riscv64 using: + - Zvknha or Zvknhb vector crypto extensions + - Zvkb vector crypto extension + endmenu diff --git a/arch/riscv/crypto/Makefile b/arch/riscv/crypto/Makefile index 94a7f8eaa8a7..e9d7717ec943 100644 --- a/arch/riscv/crypto/Makefile +++ b/arch/riscv/crypto/Makefile @@ -12,6 +12,9 @@ aes-block-riscv64-y := aes-riscv64-block-mode-glue.o aes-riscv64-zvkned-zvbb-zvk obj-$(CONFIG_CRYPTO_GHASH_RISCV64) += ghash-riscv64.o ghash-riscv64-y := ghash-riscv64-glue.o ghash-riscv64-zvkg.o +obj-$(CONFIG_CRYPTO_SHA256_RISCV64) += sha256-riscv64.o +sha256-riscv64-y := sha256-riscv64-glue.o sha256-riscv64-zvknha_or_zvknhb-zvkb.o + quiet_cmd_perlasm = PERLASM $@ cmd_perlasm = $(PERL) $(<) void $(@) @@ -27,7 +30,11 @@ $(obj)/aes-riscv64-zvkned-zvkb.S: $(src)/aes-riscv64-zvkned-zvkb.pl $(obj)/ghash-riscv64-zvkg.S: $(src)/ghash-riscv64-zvkg.pl $(call cmd,perlasm) +$(obj)/sha256-riscv64-zvknha_or_zvknhb-zvkb.S: $(src)/sha256-riscv64-zvknha_or_zvknhb-zvkb.pl + $(call cmd,perlasm) + clean-files += aes-riscv64-zvkned.S clean-files += aes-riscv64-zvkned-zvbb-zvkg.S clean-files += aes-riscv64-zvkned-zvkb.S clean-files += ghash-riscv64-zvkg.S +clean-files += sha256-riscv64-zvknha_or_zvknhb-zvkb.S diff --git a/arch/riscv/crypto/sha256-riscv64-glue.c b/arch/riscv/crypto/sha256-riscv64-glue.c new file mode 100644 index 000000000000..760d89031d1c --- /dev/null +++ b/arch/riscv/crypto/sha256-riscv64-glue.c @@ -0,0 +1,145 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Linux/riscv64 port of the OpenSSL SHA256 implementation for RISC-V 64 + * + * Copyright (C) 2022 VRULL GmbH + * Author: Heiko Stuebner <heiko.stuebner@xxxxxxxx> + * + * Copyright (C) 2023 SiFive, Inc. + * Author: Jerry Shih <jerry.shih@xxxxxxxxxx> + */ + +#include <asm/simd.h> +#include <asm/vector.h> +#include <linux/linkage.h> +#include <linux/module.h> +#include <linux/types.h> +#include <crypto/internal/hash.h> +#include <crypto/internal/simd.h> +#include <crypto/sha256_base.h> + +/* + * sha256 using zvkb and zvknha/b vector crypto extension + * + * This asm function will just take the first 256-bit as the sha256 state from + * the pointer to `struct sha256_state`. + */ +asmlinkage void +sha256_block_data_order_zvkb_zvknha_or_zvknhb(struct sha256_state *digest, + const u8 *data, int num_blks); + +static int riscv64_sha256_update(struct shash_desc *desc, const u8 *data, + unsigned int len) +{ + int ret = 0; + + /* + * Make sure struct sha256_state begins directly with the SHA256 + * 256-bit internal state, as this is what the asm function expect. + */ + BUILD_BUG_ON(offsetof(struct sha256_state, state) != 0); + + if (crypto_simd_usable()) { + kernel_vector_begin(); + ret = sha256_base_do_update( + desc, data, len, + sha256_block_data_order_zvkb_zvknha_or_zvknhb); + kernel_vector_end(); + } else { + ret = crypto_sha256_update(desc, data, len); + } + + return ret; +} + +static int riscv64_sha256_finup(struct shash_desc *desc, const u8 *data, + unsigned int len, u8 *out) +{ + if (crypto_simd_usable()) { + kernel_vector_begin(); + if (len) + sha256_base_do_update( + desc, data, len, + sha256_block_data_order_zvkb_zvknha_or_zvknhb); + sha256_base_do_finalize( + desc, sha256_block_data_order_zvkb_zvknha_or_zvknhb); + kernel_vector_end(); + + return sha256_base_finish(desc, out); + } + + return crypto_sha256_finup(desc, data, len, out); +} + +static int riscv64_sha256_final(struct shash_desc *desc, u8 *out) +{ + return riscv64_sha256_finup(desc, NULL, 0, out); +} + +static struct shash_alg sha256_algs[] = { + { + .init = sha256_base_init, + .update = riscv64_sha256_update, + .final = riscv64_sha256_final, + .finup = riscv64_sha256_finup, + .descsize = sizeof(struct sha256_state), + .digestsize = SHA256_DIGEST_SIZE, + .base = { + .cra_blocksize = SHA256_BLOCK_SIZE, + .cra_priority = 150, + .cra_name = "sha256", + .cra_driver_name = "sha256-riscv64-zvknha_or_zvknhb-zvkb", + .cra_module = THIS_MODULE, + }, + }, { + .init = sha224_base_init, + .update = riscv64_sha256_update, + .final = riscv64_sha256_final, + .finup = riscv64_sha256_finup, + .descsize = sizeof(struct sha256_state), + .digestsize = SHA224_DIGEST_SIZE, + .base = { + .cra_blocksize = SHA224_BLOCK_SIZE, + .cra_priority = 150, + .cra_name = "sha224", + .cra_driver_name = "sha224-riscv64-zvknha_or_zvknhb-zvkb", + .cra_module = THIS_MODULE, + }, + }, +}; + +static inline bool check_sha256_ext(void) +{ + /* + * From the spec: + * The Zvknhb ext supports both SHA-256 and SHA-512 and Zvknha only + * supports SHA-256. + */ + return (riscv_isa_extension_available(NULL, ZVKNHA) || + riscv_isa_extension_available(NULL, ZVKNHB)) && + riscv_isa_extension_available(NULL, ZVKB) && + riscv_vector_vlen() >= 128; +} + +static int __init riscv64_sha256_mod_init(void) +{ + if (check_sha256_ext()) + return crypto_register_shashes(sha256_algs, + ARRAY_SIZE(sha256_algs)); + + return -ENODEV; +} + +static void __exit riscv64_sha256_mod_fini(void) +{ + crypto_unregister_shashes(sha256_algs, ARRAY_SIZE(sha256_algs)); +} + +module_init(riscv64_sha256_mod_init); +module_exit(riscv64_sha256_mod_fini); + +MODULE_DESCRIPTION("SHA-256 (RISC-V accelerated)"); +MODULE_AUTHOR("Heiko Stuebner <heiko.stuebner@xxxxxxxx>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_CRYPTO("sha224"); +MODULE_ALIAS_CRYPTO("sha256"); diff --git a/arch/riscv/crypto/sha256-riscv64-zvknha_or_zvknhb-zvkb.pl b/arch/riscv/crypto/sha256-riscv64-zvknha_or_zvknhb-zvkb.pl new file mode 100644 index 000000000000..22dd40d8c734 --- /dev/null +++ b/arch/riscv/crypto/sha256-riscv64-zvknha_or_zvknhb-zvkb.pl @@ -0,0 +1,317 @@ +#! /usr/bin/env perl +# SPDX-License-Identifier: Apache-2.0 OR BSD-2-Clause +# +# This file is dual-licensed, meaning that you can use it under your +# choice of either of the following two licenses: +# +# Copyright 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) 2023, Christoph Müllner <christoph.muellner@xxxxxxxx> +# Copyright (c) 2023, Phoebe Chen <phoebe.chen@xxxxxxxxxx> +# 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. + +# The generated code of this file depends on the following RISC-V extensions: +# - RV64I +# - RISC-V Vector ('V') with VLEN >= 128 +# - RISC-V Vector SHA-2 Secure Hash extension ('Zvknha' or 'Zvknhb') +# - RISC-V Vector Cryptography Bit-manipulation extension ('Zvkb') + +use strict; +use warnings; + +use FindBin qw($Bin); +use lib "$Bin"; +use lib "$Bin/../../perlasm"; + +# $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 +my $output = $#ARGV >= 0 && $ARGV[$#ARGV] =~ m|\.\w+$| ? pop : undef; +my $flavour = $#ARGV >= 0 && $ARGV[0] !~ m|\.| ? shift : undef; + +$output and open STDOUT,">$output"; + +my $code=<<___; +#include <linux/cfi_types.h> + +.text +.option arch, +zvknha, +zvkb +___ + +my ($V0, $V1, $V2, $V3, $V4, $V5, $V6, $V7, + $V8, $V9, $V10, $V11, $V12, $V13, $V14, $V15, + $V16, $V17, $V18, $V19, $V20, $V21, $V22, $V23, + $V24, $V25, $V26, $V27, $V28, $V29, $V30, $V31, +) = map("v$_",(0..31)); + +my $K256 = "K256"; + +# Function arguments +my ($H, $INP, $LEN, $KT, $H2, $INDEX_PATTERN) = ("a0", "a1", "a2", "a3", "t3", "t4"); + +sub sha_256_load_constant { + my $code=<<___; + la $KT, $K256 # Load round constants K256 + vle32.v $V10, ($KT) + addi $KT, $KT, 16 + vle32.v $V11, ($KT) + addi $KT, $KT, 16 + vle32.v $V12, ($KT) + addi $KT, $KT, 16 + vle32.v $V13, ($KT) + addi $KT, $KT, 16 + vle32.v $V14, ($KT) + addi $KT, $KT, 16 + vle32.v $V15, ($KT) + addi $KT, $KT, 16 + vle32.v $V16, ($KT) + addi $KT, $KT, 16 + vle32.v $V17, ($KT) + addi $KT, $KT, 16 + vle32.v $V18, ($KT) + addi $KT, $KT, 16 + vle32.v $V19, ($KT) + addi $KT, $KT, 16 + vle32.v $V20, ($KT) + addi $KT, $KT, 16 + vle32.v $V21, ($KT) + addi $KT, $KT, 16 + vle32.v $V22, ($KT) + addi $KT, $KT, 16 + vle32.v $V23, ($KT) + addi $KT, $KT, 16 + vle32.v $V24, ($KT) + addi $KT, $KT, 16 + vle32.v $V25, ($KT) +___ + + return $code; +} + +################################################################################ +# void sha256_block_data_order_zvkb_zvknha_or_zvknhb(void *c, const void *p, size_t len) +$code .= <<___; +SYM_TYPED_FUNC_START(sha256_block_data_order_zvkb_zvknha_or_zvknhb) + vsetivli zero, 4, e32, m1, ta, ma + + @{[sha_256_load_constant]} + + # H is stored as {a,b,c,d},{e,f,g,h}, but we need {f,e,b,a},{h,g,d,c} + # The dst vtype is e32m1 and the index vtype is e8mf4. + # We use index-load with the following index pattern at v26. + # i8 index: + # 20, 16, 4, 0 + # Instead of setting the i8 index, we could use a single 32bit + # little-endian value to cover the 4xi8 index. + # i32 value: + # 0x 00 04 10 14 + li $INDEX_PATTERN, 0x00041014 + vsetivli zero, 1, e32, m1, ta, ma + vmv.v.x $V26, $INDEX_PATTERN + + addi $H2, $H, 8 + + # Use index-load to get {f,e,b,a},{h,g,d,c} + vsetivli zero, 4, e32, m1, ta, ma + vluxei8.v $V6, ($H), $V26 + vluxei8.v $V7, ($H2), $V26 + + # Setup v0 mask for the vmerge to replace the first word (idx==0) in key-scheduling. + # The AVL is 4 in SHA, so we could use a single e8(8 element masking) for masking. + vsetivli zero, 1, e8, m1, ta, ma + vmv.v.i $V0, 0x01 + + vsetivli zero, 4, e32, m1, ta, ma + +L_round_loop: + # Decrement length by 1 + add $LEN, $LEN, -1 + + # Keep the current state as we need it later: H' = H+{a',b',c',...,h'}. + vmv.v.v $V30, $V6 + vmv.v.v $V31, $V7 + + # Load the 512-bits of the message block in v1-v4 and perform + # an endian swap on each 4 bytes element. + vle32.v $V1, ($INP) + vrev8.v $V1, $V1 + add $INP, $INP, 16 + vle32.v $V2, ($INP) + vrev8.v $V2, $V2 + add $INP, $INP, 16 + vle32.v $V3, ($INP) + vrev8.v $V3, $V3 + add $INP, $INP, 16 + vle32.v $V4, ($INP) + vrev8.v $V4, $V4 + add $INP, $INP, 16 + + # Quad-round 0 (+0, Wt from oldest to newest in v1->v2->v3->v4) + vadd.vv $V5, $V10, $V1 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + vmerge.vvm $V5, $V3, $V2, $V0 + vsha2ms.vv $V1, $V5, $V4 # Generate W[19:16] + + # Quad-round 1 (+1, v2->v3->v4->v1) + vadd.vv $V5, $V11, $V2 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + vmerge.vvm $V5, $V4, $V3, $V0 + vsha2ms.vv $V2, $V5, $V1 # Generate W[23:20] + + # Quad-round 2 (+2, v3->v4->v1->v2) + vadd.vv $V5, $V12, $V3 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + vmerge.vvm $V5, $V1, $V4, $V0 + vsha2ms.vv $V3, $V5, $V2 # Generate W[27:24] + + # Quad-round 3 (+3, v4->v1->v2->v3) + vadd.vv $V5, $V13, $V4 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + vmerge.vvm $V5, $V2, $V1, $V0 + vsha2ms.vv $V4, $V5, $V3 # Generate W[31:28] + + # Quad-round 4 (+0, v1->v2->v3->v4) + vadd.vv $V5, $V14, $V1 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + vmerge.vvm $V5, $V3, $V2, $V0 + vsha2ms.vv $V1, $V5, $V4 # Generate W[35:32] + + # Quad-round 5 (+1, v2->v3->v4->v1) + vadd.vv $V5, $V15, $V2 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + vmerge.vvm $V5, $V4, $V3, $V0 + vsha2ms.vv $V2, $V5, $V1 # Generate W[39:36] + + # Quad-round 6 (+2, v3->v4->v1->v2) + vadd.vv $V5, $V16, $V3 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + vmerge.vvm $V5, $V1, $V4, $V0 + vsha2ms.vv $V3, $V5, $V2 # Generate W[43:40] + + # Quad-round 7 (+3, v4->v1->v2->v3) + vadd.vv $V5, $V17, $V4 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + vmerge.vvm $V5, $V2, $V1, $V0 + vsha2ms.vv $V4, $V5, $V3 # Generate W[47:44] + + # Quad-round 8 (+0, v1->v2->v3->v4) + vadd.vv $V5, $V18, $V1 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + vmerge.vvm $V5, $V3, $V2, $V0 + vsha2ms.vv $V1, $V5, $V4 # Generate W[51:48] + + # Quad-round 9 (+1, v2->v3->v4->v1) + vadd.vv $V5, $V19, $V2 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + vmerge.vvm $V5, $V4, $V3, $V0 + vsha2ms.vv $V2, $V5, $V1 # Generate W[55:52] + + # Quad-round 10 (+2, v3->v4->v1->v2) + vadd.vv $V5, $V20, $V3 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + vmerge.vvm $V5, $V1, $V4, $V0 + vsha2ms.vv $V3, $V5, $V2 # Generate W[59:56] + + # Quad-round 11 (+3, v4->v1->v2->v3) + vadd.vv $V5, $V21, $V4 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + vmerge.vvm $V5, $V2, $V1, $V0 + vsha2ms.vv $V4, $V5, $V3 # Generate W[63:60] + + # Quad-round 12 (+0, v1->v2->v3->v4) + # Note that we stop generating new message schedule words (Wt, v1-13) + # as we already generated all the words we end up consuming (i.e., W[63:60]). + vadd.vv $V5, $V22, $V1 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + + # Quad-round 13 (+1, v2->v3->v4->v1) + vadd.vv $V5, $V23, $V2 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + + # Quad-round 14 (+2, v3->v4->v1->v2) + vadd.vv $V5, $V24, $V3 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + + # Quad-round 15 (+3, v4->v1->v2->v3) + vadd.vv $V5, $V25, $V4 + vsha2cl.vv $V7, $V6, $V5 + vsha2ch.vv $V6, $V7, $V5 + + # H' = H+{a',b',c',...,h'} + vadd.vv $V6, $V30, $V6 + vadd.vv $V7, $V31, $V7 + bnez $LEN, L_round_loop + + # Store {f,e,b,a},{h,g,d,c} back to {a,b,c,d},{e,f,g,h}. + vsuxei8.v $V6, ($H), $V26 + vsuxei8.v $V7, ($H2), $V26 + + ret +SYM_FUNC_END(sha256_block_data_order_zvkb_zvknha_or_zvknhb) + +.p2align 2 +.type $K256,\@object +$K256: + .word 0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5 + .word 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5 + .word 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3 + .word 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174 + .word 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc + .word 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da + .word 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7 + .word 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967 + .word 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13 + .word 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85 + .word 0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3 + .word 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070 + .word 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5 + .word 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3 + .word 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208 + .word 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2 +.size $K256,.-$K256 +___ + +print $code; + +close STDOUT or die "error closing STDOUT: $!"; -- 2.28.0