Re: [PATCH 4/4] Twofish cipher - x86_64 assembler

From: Joachim Fritschi
Date: Mon Jun 19 2006 - 10:13:02 EST


This patch is now based on the cryptodev tree using the new cryptoapi (crypto tfm
instead of the crypto ctx as parameter).

The module passed the tcrypt tests and testscripts.

Signed-off-by: Joachim Fritschi <jfritschi@xxxxxxxxxx>

arch/x86_64/crypto/Makefile | 3
arch/x86_64/crypto/twofish-x86_64-asm.S | 324 +++++++++++++++++++++++++++++++
arch/x86_64/crypto/twofish.c | 86 ++++++++
crypto/Kconfig | 15 +
4 files changed, 428 insertions(+), 0 deletions(-)

diff --git a/arch/x86_64/crypto/Makefile b/arch/x86_64/crypto/Makefile
index 426d20f..15b538a 100644
--- a/arch/x86_64/crypto/Makefile
+++ b/arch/x86_64/crypto/Makefile
@@ -5,5 +5,8 @@ # Arch-specific CryptoAPI modules.
#

obj-$(CONFIG_CRYPTO_AES_X86_64) += aes-x86_64.o
+obj-$(CONFIG_CRYPTO_TWOFISH_X86_64) += twofish-x86_64.o

aes-x86_64-y := aes-x86_64-asm.o aes.o
+twofish-x86_64-y := twofish-x86_64-asm.o twofish.o
+
diff --git a/arch/x86_64/crypto/twofish-x86_64-asm.S b/arch/x86_64/crypto/twofish-x86_64-asm.S
new file mode 100644
index 0000000..5b694c0
--- /dev/null
+++ b/arch/x86_64/crypto/twofish-x86_64-asm.S
@@ -0,0 +1,324 @@
+/***************************************************************************
+* Copyright (C) 2006 by Joachim Fritschi, <jfritschi@xxxxxxxxxx> *
+* *
+* This program is free software; you can redistribute it and/or modify *
+* it under the terms of the GNU General Public License as published by *
+* the Free Software Foundation; either version 2 of the License, or *
+* (at your option) any later version. *
+* *
+* This program is distributed in the hope that it will be useful, *
+* but WITHOUT ANY WARRANTY; without even the implied warranty of *
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
+* GNU General Public License for more details. *
+* *
+* You should have received a copy of the GNU General Public License *
+* along with this program; if not, write to the *
+* Free Software Foundation, Inc., *
+* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
+***************************************************************************/
+
+.file "twofish-x86_64-asm.S"
+.text
+
+#include <asm/asm-offsets.h>
+
+#define a_offset 0
+#define b_offset 4
+#define c_offset 8
+#define d_offset 12
+
+/* Structure of the crypto context struct*/
+
+#define s0 0 /* S0 Array 256 Words each */
+#define s1 1024 /* S1 Array */
+#define s2 2048 /* S2 Array */
+#define s3 3072 /* S3 Array */
+#define w 4096 /* 8 whitening keys (word) */
+#define k 4128 /* key 1-32 ( word ) */
+
+/* define a few register aliases to allow macro substitution */
+
+#define R0 %rax
+#define R0D %eax
+#define R0B %al
+#define R0H %ah
+
+#define R1 %rbx
+#define R1D %ebx
+#define R1B %bl
+#define R1H %bh
+
+#define R2 %rcx
+#define R2D %ecx
+#define R2B %cl
+#define R2H %ch
+
+#define R3 %rdx
+#define R3D %edx
+#define R3B %dl
+#define R3H %dh
+
+
+/* performs input whitening */
+#define input_whitening(src,context,offset)\
+ xor w+offset(context), src;
+
+/* performs input whitening */
+#define output_whitening(src,context,offset)\
+ xor w+16+offset(context), src;
+
+
+/*
+a input register containing a (rotated 16)
+b input register containing b
+c input register containing c
+d input register containing d (already rol $1)
+operations on a and b are interleaved to increase performance
+*/
+#define encrypt_round(a,b,c,d,round)\
+movzx b ## B, %edi;\
+mov s1(%r11,%rdi,4),%r8d;\
+movzx a ## B, %edi;\
+mov s2(%r11,%rdi,4),%r9d;\
+movzx b ## H, %edi;\
+ror $16, b ## D;\
+xor s2(%r11,%rdi,4),%r8d;\
+movzx a ## H, %edi;\
+ror $16, a ## D;\
+xor s3(%r11,%rdi,4),%r9d;\
+movzx b ## B, %edi;\
+xor s3(%r11,%rdi,4),%r8d;\
+movzx a ## B, %edi;\
+xor (%r11,%rdi,4), %r9d;\
+movzx b ## H, %edi;\
+ror $15, b ## D;\
+xor (%r11,%rdi,4), %r8d;\
+movzx a ## H, %edi;\
+xor s1(%r11,%rdi,4),%r9d;\
+add %r8d, %r9d;\
+add %r9d, %r8d;\
+add k+round(%r11), %r9d;\
+xor %r9d, c ## D;\
+rol $15, c ## D;\
+add k+4+round(%r11),%r8d;\
+xor %r8d, d ## D;
+
+/*
+a input register containing a(rotated 16)
+b input register containing b
+c input register containing c
+d input register containing d (already rol $1)
+operations on a and b are interleaved to increase performance
+during the round a and b are prepared for the output whitening
+*/
+#define encrypt_last_round(a,b,c,d,round)\
+mov b ## D, %r10d;\
+shl $32, %r10;\
+movzx b ## B, %edi;\
+mov s1(%r11,%rdi,4),%r8d;\
+movzx a ## B, %edi;\
+mov s2(%r11,%rdi,4),%r9d;\
+movzx b ## H, %edi;\
+ror $16, b ## D;\
+xor s2(%r11,%rdi,4),%r8d;\
+movzx a ## H, %edi;\
+ror $16, a ## D;\
+xor s3(%r11,%rdi,4),%r9d;\
+movzx b ## B, %edi;\
+xor s3(%r11,%rdi,4),%r8d;\
+movzx a ## B, %edi;\
+xor (%r11,%rdi,4), %r9d;\
+xor a, %r10;\
+movzx b ## H, %edi;\
+xor (%r11,%rdi,4), %r8d;\
+movzx a ## H, %edi;\
+xor s1(%r11,%rdi,4),%r9d;\
+add %r8d, %r9d;\
+add %r9d, %r8d;\
+add k+round(%r11), %r9d;\
+xor %r9d, c ## D;\
+ror $1, c ## D;\
+add k+4+round(%r11),%r8d;\
+xor %r8d, d ## D
+
+/*
+a input register containing a
+b input register containing b (rotated 16)
+c input register containing c (already rol $1)
+d input register containing d
+operations on a and b are interleaved to increase performance
+*/
+#define decrypt_round(a,b,c,d,round)\
+movzx a ## B, %edi;\
+mov (%r11,%rdi,4), %r9d;\
+movzx b ## B, %edi;\
+mov s3(%r11,%rdi,4),%r8d;\
+movzx a ## H, %edi;\
+ror $16, a ## D;\
+xor s1(%r11,%rdi,4),%r9d;\
+movzx b ## H, %edi;\
+ror $16, b ## D;\
+xor (%r11,%rdi,4), %r8d;\
+movzx a ## B, %edi;\
+xor s2(%r11,%rdi,4),%r9d;\
+movzx b ## B, %edi;\
+xor s1(%r11,%rdi,4),%r8d;\
+movzx a ## H, %edi;\
+ror $15, a ## D;\
+xor s3(%r11,%rdi,4),%r9d;\
+movzx b ## H, %edi;\
+xor s2(%r11,%rdi,4),%r8d;\
+add %r8d, %r9d;\
+add %r9d, %r8d;\
+add k+round(%r11), %r9d;\
+xor %r9d, c ## D;\
+add k+4+round(%r11),%r8d;\
+xor %r8d, d ## D;\
+rol $15, d ## D;
+
+/*
+a input register containing a
+b input register containing b
+c input register containing c (already rol $1)
+d input register containing d
+operations on a and b are interleaved to increase performance
+during the round a and b are prepared for the output whitening
+*/
+#define decrypt_last_round(a,b,c,d,round)\
+movzx a ## B, %edi;\
+mov (%r11,%rdi,4), %r9d;\
+movzx b ## B, %edi;\
+mov s3(%r11,%rdi,4),%r8d;\
+movzx b ## H, %edi;\
+ror $16, b ## D;\
+xor (%r11,%rdi,4), %r8d;\
+movzx a ## H, %edi;\
+mov b ## D, %r10d;\
+shl $32, %r10;\
+xor a, %r10;\
+ror $16, a ## D;\
+xor s1(%r11,%rdi,4),%r9d;\
+movzx b ## B, %edi;\
+xor s1(%r11,%rdi,4),%r8d;\
+movzx a ## B, %edi;\
+xor s2(%r11,%rdi,4),%r9d;\
+movzx b ## H, %edi;\
+xor s2(%r11,%rdi,4),%r8d;\
+movzx a ## H, %edi;\
+xor s3(%r11,%rdi,4),%r9d;\
+add %r8d, %r9d;\
+add %r9d, %r8d;\
+add k+round(%r11), %r9d;\
+xor %r9d, c ## D;\
+add k+4+round(%r11),%r8d;\
+xor %r8d, d ## D;\
+ror $1, d ## D;
+
+.align 8
+.global twofish_enc_blk
+.global twofish_dec_blk
+
+twofish_enc_blk:
+ pushq R1
+
+ /* %rdi contains the crypto tfm adress */
+ /* %rsi contains the output adress */
+ /* %rdx contains the input adress */
+ add $crypto_tfm_ctx_offset, %rdi /* set ctx adress */
+ /* ctx adress is moved to free one non-rex register
+ as target for the 8bit high operations */
+ mov %rdi, %r11
+
+ movq (R3), R1
+ movq 8(R3), R3
+ input_whitening(R1,%r11,a_offset)
+ input_whitening(R3,%r11,c_offset)
+ mov R1D, R0D
+ rol $16, R0D
+ shr $32, R1
+ mov R3D, R2D
+ shr $32, R3
+ rol $1, R3D
+
+ encrypt_round(R0,R1,R2,R3,0);
+ encrypt_round(R2,R3,R0,R1,8);
+ encrypt_round(R0,R1,R2,R3,2*8);
+ encrypt_round(R2,R3,R0,R1,3*8);
+ encrypt_round(R0,R1,R2,R3,4*8);
+ encrypt_round(R2,R3,R0,R1,5*8);
+ encrypt_round(R0,R1,R2,R3,6*8);
+ encrypt_round(R2,R3,R0,R1,7*8);
+ encrypt_round(R0,R1,R2,R3,8*8);
+ encrypt_round(R2,R3,R0,R1,9*8);
+ encrypt_round(R0,R1,R2,R3,10*8);
+ encrypt_round(R2,R3,R0,R1,11*8);
+ encrypt_round(R0,R1,R2,R3,12*8);
+ encrypt_round(R2,R3,R0,R1,13*8);
+ encrypt_round(R0,R1,R2,R3,14*8);
+ encrypt_last_round(R2,R3,R0,R1,15*8);
+
+
+ output_whitening(%r10,%r11,a_offset)
+ movq %r10, (%rsi)
+
+ shl $32, R1
+ xor R0, R1
+
+ output_whitening(R1,%r11,c_offset)
+ movq R1, 8(%rsi)
+
+ popq R1
+ movq $1,%rax
+ ret
+
+twofish_dec_blk:
+ pushq R1
+
+ /* %rdi contains the crypto tfm adress */
+ /* %rsi contains the output adress */
+ /* %rdx contains the input adress */
+ add $crypto_tfm_ctx_offset, %rdi /* set ctx adress */
+ /* ctx adress is moved to free one non-rex register
+ as target for the 8bit high operations */
+ mov %rdi, %r11
+
+ movq (R3), R1
+ movq 8(R3), R3
+ output_whitening(R1,%r11,a_offset)
+ output_whitening(R3,%r11,c_offset)
+ mov R1D, R0D
+ shr $32, R1
+ rol $16, R1D
+ mov R3D, R2D
+ shr $32, R3
+ rol $1, R2D
+
+ decrypt_round(R0,R1,R2,R3,15*8);
+ decrypt_round(R2,R3,R0,R1,14*8);
+ decrypt_round(R0,R1,R2,R3,13*8);
+ decrypt_round(R2,R3,R0,R1,12*8);
+ decrypt_round(R0,R1,R2,R3,11*8);
+ decrypt_round(R2,R3,R0,R1,10*8);
+ decrypt_round(R0,R1,R2,R3,9*8);
+ decrypt_round(R2,R3,R0,R1,8*8);
+ decrypt_round(R0,R1,R2,R3,7*8);
+ decrypt_round(R2,R3,R0,R1,6*8);
+ decrypt_round(R0,R1,R2,R3,5*8);
+ decrypt_round(R2,R3,R0,R1,4*8);
+ decrypt_round(R0,R1,R2,R3,3*8);
+ decrypt_round(R2,R3,R0,R1,2*8);
+ decrypt_round(R0,R1,R2,R3,1*8);
+ decrypt_last_round(R2,R3,R0,R1,0);
+
+ input_whitening(%r10,%r11,a_offset)
+ movq %r10, (%rsi)
+
+ shl $32, R1
+ xor R0, R1
+
+ input_whitening(R1,%r11,c_offset)
+ movq R1, 8(%rsi)
+
+ popq R1
+ movq $1,%rax
+ ret
diff --git a/arch/x86_64/crypto/twofish.c b/arch/x86_64/crypto/twofish.c
new file mode 100644
index 0000000..e38cc95
--- /dev/null
+++ b/arch/x86_64/crypto/twofish.c
@@ -0,0 +1,86 @@
+/*
+ * Glue Code for optimized x86_64 assembler version of TWOFISH
+ *
+ * Originally Twofish for GPG
+ * By Matthew Skala <mskala@xxxxxxxxxxxxxxxxx>, July 26, 1998
+ * 256-bit key length added March 20, 1999
+ * Some modifications to reduce the text size by Werner Koch, April, 1998
+ * Ported to the kerneli patch by Marc Mutz <Marc@xxxxxxxx>
+ * Ported to CryptoAPI by Colin Slater <hoho@xxxxxxxxxxxx>
+ *
+ * The original author has disclaimed all copyright interest in this
+ * code and thus put it in the public domain. The subsequent authors
+ * have put this under the GNU General Public License.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+ * USA
+ *
+ * This code is a "clean room" implementation, written from the paper
+ * _Twofish: A 128-Bit Block Cipher_ by Bruce Schneier, John Kelsey,
+ * Doug Whiting, David Wagner, Chris Hall, and Niels Ferguson, available
+ * through http://www.counterpane.com/twofish.html
+ *
+ * For background information on multiplication in finite fields, used for
+ * the matrix operations in the key schedule, see the book _Contemporary
+ * Abstract Algebra_ by Joseph A. Gallian, especially chapter 22 in the
+ * Third Edition.
+ */
+
+#include <asm/byteorder.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/crypto.h>
+#include <linux/bitops.h>
+#include <crypto/twofish.h>
+
+asmlinkage void twofish_enc_blk(struct crypto_tfm *tfm, u8 *dst, const u8 *src);
+
+asmlinkage void twofish_dec_blk(struct crypto_tfm *tfm, u8 *dst, const u8 *src);
+
+static struct crypto_alg alg = {
+ .cra_name = "twofish",
+ .cra_driver_name = "twofish-x86_64",
+ .cra_priority = 200,
+ .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
+ .cra_blocksize = TF_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct twofish_ctx),
+ .cra_alignmask = 3,
+ .cra_module = THIS_MODULE,
+ .cra_list = LIST_HEAD_INIT(alg.cra_list),
+ .cra_u = { .cipher = {
+ .cia_min_keysize = TF_MIN_KEY_SIZE,
+ .cia_max_keysize = TF_MAX_KEY_SIZE,
+ .cia_setkey = twofish_setkey,
+ .cia_encrypt = twofish_enc_blk,
+ .cia_decrypt = twofish_dec_blk } }
+};
+
+static int __init init(void)
+{
+ return crypto_register_alg(&alg);
+}
+
+static void __exit fini(void)
+{
+ crypto_unregister_alg(&alg);
+}
+
+module_init(init);
+module_exit(fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION ("Twofish Cipher Algorithm, x86_64 asm optimized");
diff --git a/crypto/Kconfig b/crypto/Kconfig
index 28b203b..990054d 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -165,6 +165,21 @@ config CRYPTO_TWOFISH_586
See also:
<http://www.schneier.com/twofish.html>

+config CRYPTO_TWOFISH_X86_64
+ tristate "Twofish cipher algorithm (x86_64)"
+ depends on CRYPTO && ((X86 || UML_X86) && 64BIT)
+ select CRYPTO_TWOFISH_COMMON
+ help
+ Twofish cipher algorithm (x86_64).
+
+ Twofish was submitted as an AES (Advanced Encryption Standard)
+ candidate cipher by researchers at CounterPane Systems. It is a
+ 16 round block cipher supporting key sizes of 128, 192, and 256
+ bits.
+
+ See also:
+ <http://www.schneier.com/twofish.html>
+
config CRYPTO_SERPENT
tristate "Serpent cipher algorithm"
depends on CRYPTO
-
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