crypto: chacha20 - Add a SSSE3 SIMD variant for x86_64

Implements an x86_64 assembler driver for the ChaCha20 stream cipher. This
single block variant works on a single state matrix using SSE instructions.
It requires SSSE3 due the use of pshufb for efficient 8/16-bit rotate
operations.

For large messages, throughput increases by ~65% compared to
chacha20-generic:

testing speed of chacha20 (chacha20-generic) encryption
test 0 (256 bit key, 16 byte blocks): 45089207 operations in 10 seconds (721427312 bytes)
test 1 (256 bit key, 64 byte blocks): 43839521 operations in 10 seconds (2805729344 bytes)
test 2 (256 bit key, 256 byte blocks): 12702056 operations in 10 seconds (3251726336 bytes)
test 3 (256 bit key, 1024 byte blocks): 3371173 operations in 10 seconds (3452081152 bytes)
test 4 (256 bit key, 8192 byte blocks): 422468 operations in 10 seconds (3460857856 bytes)

testing speed of chacha20 (chacha20-simd) encryption
test 0 (256 bit key, 16 byte blocks): 43141886 operations in 10 seconds (690270176 bytes)
test 1 (256 bit key, 64 byte blocks): 46845874 operations in 10 seconds (2998135936 bytes)
test 2 (256 bit key, 256 byte blocks): 18458512 operations in 10 seconds (4725379072 bytes)
test 3 (256 bit key, 1024 byte blocks): 5360533 operations in 10 seconds (5489185792 bytes)
test 4 (256 bit key, 8192 byte blocks): 692846 operations in 10 seconds (5675794432 bytes)

Benchmark results from a Core i5-4670T.

Signed-off-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Martin Willi 2015-07-16 19:14:01 +02:00 committed by Herbert Xu
parent 31d7247da5
commit c9320b6dcb
4 changed files with 282 additions and 0 deletions

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@ -20,6 +20,7 @@ obj-$(CONFIG_CRYPTO_BLOWFISH_X86_64) += blowfish-x86_64.o
obj-$(CONFIG_CRYPTO_TWOFISH_X86_64) += twofish-x86_64.o
obj-$(CONFIG_CRYPTO_TWOFISH_X86_64_3WAY) += twofish-x86_64-3way.o
obj-$(CONFIG_CRYPTO_SALSA20_X86_64) += salsa20-x86_64.o
obj-$(CONFIG_CRYPTO_CHACHA20_X86_64) += chacha20-x86_64.o
obj-$(CONFIG_CRYPTO_SERPENT_SSE2_X86_64) += serpent-sse2-x86_64.o
obj-$(CONFIG_CRYPTO_AES_NI_INTEL) += aesni-intel.o
obj-$(CONFIG_CRYPTO_GHASH_CLMUL_NI_INTEL) += ghash-clmulni-intel.o
@ -60,6 +61,7 @@ blowfish-x86_64-y := blowfish-x86_64-asm_64.o blowfish_glue.o
twofish-x86_64-y := twofish-x86_64-asm_64.o twofish_glue.o
twofish-x86_64-3way-y := twofish-x86_64-asm_64-3way.o twofish_glue_3way.o
salsa20-x86_64-y := salsa20-x86_64-asm_64.o salsa20_glue.o
chacha20-x86_64-y := chacha20-ssse3-x86_64.o chacha20_glue.o
serpent-sse2-x86_64-y := serpent-sse2-x86_64-asm_64.o serpent_sse2_glue.o
ifeq ($(avx_supported),yes)

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@ -0,0 +1,142 @@
/*
* ChaCha20 256-bit cipher algorithm, RFC7539, x64 SSSE3 functions
*
* Copyright (C) 2015 Martin Willi
*
* 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.
*/
#include <linux/linkage.h>
.data
.align 16
ROT8: .octa 0x0e0d0c0f0a09080b0605040702010003
ROT16: .octa 0x0d0c0f0e09080b0a0504070601000302
.text
ENTRY(chacha20_block_xor_ssse3)
# %rdi: Input state matrix, s
# %rsi: 1 data block output, o
# %rdx: 1 data block input, i
# This function encrypts one ChaCha20 block by loading the state matrix
# in four SSE registers. It performs matrix operation on four words in
# parallel, but requireds shuffling to rearrange the words after each
# round. 8/16-bit word rotation is done with the slightly better
# performing SSSE3 byte shuffling, 7/12-bit word rotation uses
# traditional shift+OR.
# x0..3 = s0..3
movdqa 0x00(%rdi),%xmm0
movdqa 0x10(%rdi),%xmm1
movdqa 0x20(%rdi),%xmm2
movdqa 0x30(%rdi),%xmm3
movdqa %xmm0,%xmm8
movdqa %xmm1,%xmm9
movdqa %xmm2,%xmm10
movdqa %xmm3,%xmm11
movdqa ROT8(%rip),%xmm4
movdqa ROT16(%rip),%xmm5
mov $10,%ecx
.Ldoubleround:
# x0 += x1, x3 = rotl32(x3 ^ x0, 16)
paddd %xmm1,%xmm0
pxor %xmm0,%xmm3
pshufb %xmm5,%xmm3
# x2 += x3, x1 = rotl32(x1 ^ x2, 12)
paddd %xmm3,%xmm2
pxor %xmm2,%xmm1
movdqa %xmm1,%xmm6
pslld $12,%xmm6
psrld $20,%xmm1
por %xmm6,%xmm1
# x0 += x1, x3 = rotl32(x3 ^ x0, 8)
paddd %xmm1,%xmm0
pxor %xmm0,%xmm3
pshufb %xmm4,%xmm3
# x2 += x3, x1 = rotl32(x1 ^ x2, 7)
paddd %xmm3,%xmm2
pxor %xmm2,%xmm1
movdqa %xmm1,%xmm7
pslld $7,%xmm7
psrld $25,%xmm1
por %xmm7,%xmm1
# x1 = shuffle32(x1, MASK(0, 3, 2, 1))
pshufd $0x39,%xmm1,%xmm1
# x2 = shuffle32(x2, MASK(1, 0, 3, 2))
pshufd $0x4e,%xmm2,%xmm2
# x3 = shuffle32(x3, MASK(2, 1, 0, 3))
pshufd $0x93,%xmm3,%xmm3
# x0 += x1, x3 = rotl32(x3 ^ x0, 16)
paddd %xmm1,%xmm0
pxor %xmm0,%xmm3
pshufb %xmm5,%xmm3
# x2 += x3, x1 = rotl32(x1 ^ x2, 12)
paddd %xmm3,%xmm2
pxor %xmm2,%xmm1
movdqa %xmm1,%xmm6
pslld $12,%xmm6
psrld $20,%xmm1
por %xmm6,%xmm1
# x0 += x1, x3 = rotl32(x3 ^ x0, 8)
paddd %xmm1,%xmm0
pxor %xmm0,%xmm3
pshufb %xmm4,%xmm3
# x2 += x3, x1 = rotl32(x1 ^ x2, 7)
paddd %xmm3,%xmm2
pxor %xmm2,%xmm1
movdqa %xmm1,%xmm7
pslld $7,%xmm7
psrld $25,%xmm1
por %xmm7,%xmm1
# x1 = shuffle32(x1, MASK(2, 1, 0, 3))
pshufd $0x93,%xmm1,%xmm1
# x2 = shuffle32(x2, MASK(1, 0, 3, 2))
pshufd $0x4e,%xmm2,%xmm2
# x3 = shuffle32(x3, MASK(0, 3, 2, 1))
pshufd $0x39,%xmm3,%xmm3
dec %ecx
jnz .Ldoubleround
# o0 = i0 ^ (x0 + s0)
movdqu 0x00(%rdx),%xmm4
paddd %xmm8,%xmm0
pxor %xmm4,%xmm0
movdqu %xmm0,0x00(%rsi)
# o1 = i1 ^ (x1 + s1)
movdqu 0x10(%rdx),%xmm5
paddd %xmm9,%xmm1
pxor %xmm5,%xmm1
movdqu %xmm1,0x10(%rsi)
# o2 = i2 ^ (x2 + s2)
movdqu 0x20(%rdx),%xmm6
paddd %xmm10,%xmm2
pxor %xmm6,%xmm2
movdqu %xmm2,0x20(%rsi)
# o3 = i3 ^ (x3 + s3)
movdqu 0x30(%rdx),%xmm7
paddd %xmm11,%xmm3
pxor %xmm7,%xmm3
movdqu %xmm3,0x30(%rsi)
ret
ENDPROC(chacha20_block_xor_ssse3)

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@ -0,0 +1,123 @@
/*
* ChaCha20 256-bit cipher algorithm, RFC7539, SIMD glue code
*
* Copyright (C) 2015 Martin Willi
*
* 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.
*/
#include <crypto/algapi.h>
#include <crypto/chacha20.h>
#include <linux/crypto.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <asm/fpu/api.h>
#include <asm/simd.h>
#define CHACHA20_STATE_ALIGN 16
asmlinkage void chacha20_block_xor_ssse3(u32 *state, u8 *dst, const u8 *src);
static void chacha20_dosimd(u32 *state, u8 *dst, const u8 *src,
unsigned int bytes)
{
u8 buf[CHACHA20_BLOCK_SIZE];
while (bytes >= CHACHA20_BLOCK_SIZE) {
chacha20_block_xor_ssse3(state, dst, src);
bytes -= CHACHA20_BLOCK_SIZE;
src += CHACHA20_BLOCK_SIZE;
dst += CHACHA20_BLOCK_SIZE;
state[12]++;
}
if (bytes) {
memcpy(buf, src, bytes);
chacha20_block_xor_ssse3(state, buf, buf);
memcpy(dst, buf, bytes);
}
}
static int chacha20_simd(struct blkcipher_desc *desc, struct scatterlist *dst,
struct scatterlist *src, unsigned int nbytes)
{
u32 *state, state_buf[16 + (CHACHA20_STATE_ALIGN / sizeof(u32)) - 1];
struct blkcipher_walk walk;
int err;
if (!may_use_simd())
return crypto_chacha20_crypt(desc, dst, src, nbytes);
state = (u32 *)roundup((uintptr_t)state_buf, CHACHA20_STATE_ALIGN);
blkcipher_walk_init(&walk, dst, src, nbytes);
err = blkcipher_walk_virt_block(desc, &walk, CHACHA20_BLOCK_SIZE);
crypto_chacha20_init(state, crypto_blkcipher_ctx(desc->tfm), walk.iv);
kernel_fpu_begin();
while (walk.nbytes >= CHACHA20_BLOCK_SIZE) {
chacha20_dosimd(state, walk.dst.virt.addr, walk.src.virt.addr,
rounddown(walk.nbytes, CHACHA20_BLOCK_SIZE));
err = blkcipher_walk_done(desc, &walk,
walk.nbytes % CHACHA20_BLOCK_SIZE);
}
if (walk.nbytes) {
chacha20_dosimd(state, walk.dst.virt.addr, walk.src.virt.addr,
walk.nbytes);
err = blkcipher_walk_done(desc, &walk, 0);
}
kernel_fpu_end();
return err;
}
static struct crypto_alg alg = {
.cra_name = "chacha20",
.cra_driver_name = "chacha20-simd",
.cra_priority = 300,
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
.cra_blocksize = 1,
.cra_type = &crypto_blkcipher_type,
.cra_ctxsize = sizeof(struct chacha20_ctx),
.cra_alignmask = sizeof(u32) - 1,
.cra_module = THIS_MODULE,
.cra_u = {
.blkcipher = {
.min_keysize = CHACHA20_KEY_SIZE,
.max_keysize = CHACHA20_KEY_SIZE,
.ivsize = CHACHA20_IV_SIZE,
.geniv = "seqiv",
.setkey = crypto_chacha20_setkey,
.encrypt = chacha20_simd,
.decrypt = chacha20_simd,
},
},
};
static int __init chacha20_simd_mod_init(void)
{
if (!cpu_has_ssse3)
return -ENODEV;
return crypto_register_alg(&alg);
}
static void __exit chacha20_simd_mod_fini(void)
{
crypto_unregister_alg(&alg);
}
module_init(chacha20_simd_mod_init);
module_exit(chacha20_simd_mod_fini);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Martin Willi <martin@strongswan.org>");
MODULE_DESCRIPTION("chacha20 cipher algorithm, SIMD accelerated");
MODULE_ALIAS_CRYPTO("chacha20");
MODULE_ALIAS_CRYPTO("chacha20-simd");

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@ -1213,6 +1213,21 @@ config CRYPTO_CHACHA20
See also:
<http://cr.yp.to/chacha/chacha-20080128.pdf>
config CRYPTO_CHACHA20_X86_64
tristate "ChaCha20 cipher algorithm (x86_64/SSSE3)"
depends on X86 && 64BIT
select CRYPTO_BLKCIPHER
select CRYPTO_CHACHA20
help
ChaCha20 cipher algorithm, RFC7539.
ChaCha20 is a 256-bit high-speed stream cipher designed by Daniel J.
Bernstein and further specified in RFC7539 for use in IETF protocols.
This is the x86_64 assembler implementation using SIMD instructions.
See also:
<http://cr.yp.to/chacha/chacha-20080128.pdf>
config CRYPTO_SEED
tristate "SEED cipher algorithm"
select CRYPTO_ALGAPI