crypto: x86/chacha20 - add XChaCha20 support
Add an XChaCha20 implementation that is hooked up to the x86_64 SIMD implementations of ChaCha20. This can be used by Adiantum. An SSSE3 implementation of single-block HChaCha20 is also added so that XChaCha20 can use it rather than the generic implementation. This required refactoring the ChaCha permutation into its own function. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Eric Biggers
Herbert Xu
parent
0f961f9f67
commit
4af7826187
|
|
@ -10,6 +10,7 @@
|
|||
*/
|
||||
|
||||
#include <linux/linkage.h>
|
||||
#include <asm/frame.h>
|
||||
|
||||
.section .rodata.cst16.ROT8, "aM", @progbits, 16
|
||||
.align 16
|
||||
|
|
@ -23,37 +24,24 @@ CTRINC: .octa 0x00000003000000020000000100000000
|
|||
|
||||
.text
|
||||
|
||||
ENTRY(chacha20_block_xor_ssse3)
|
||||
# %rdi: Input state matrix, s
|
||||
# %rsi: up to 1 data block output, o
|
||||
# %rdx: up to 1 data block input, i
|
||||
# %rcx: input/output length in bytes
|
||||
|
||||
# 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 requires 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
|
||||
/*
|
||||
* chacha20_permute - permute one block
|
||||
*
|
||||
* Permute one 64-byte block where the state matrix is in %xmm0-%xmm3. This
|
||||
* function performs matrix operations on four words in parallel, but requires
|
||||
* 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.
|
||||
*
|
||||
* Clobbers: %ecx, %xmm4-%xmm7
|
||||
*/
|
||||
chacha20_permute:
|
||||
|
||||
movdqa ROT8(%rip),%xmm4
|
||||
movdqa ROT16(%rip),%xmm5
|
||||
|
||||
mov %rcx,%rax
|
||||
mov $10,%ecx
|
||||
|
||||
.Ldoubleround:
|
||||
|
||||
# x0 += x1, x3 = rotl32(x3 ^ x0, 16)
|
||||
paddd %xmm1,%xmm0
|
||||
pxor %xmm0,%xmm3
|
||||
|
|
@ -123,6 +111,29 @@ ENTRY(chacha20_block_xor_ssse3)
|
|||
dec %ecx
|
||||
jnz .Ldoubleround
|
||||
|
||||
ret
|
||||
ENDPROC(chacha20_permute)
|
||||
|
||||
ENTRY(chacha20_block_xor_ssse3)
|
||||
# %rdi: Input state matrix, s
|
||||
# %rsi: up to 1 data block output, o
|
||||
# %rdx: up to 1 data block input, i
|
||||
# %rcx: input/output length in bytes
|
||||
FRAME_BEGIN
|
||||
|
||||
# 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
|
||||
|
||||
mov %rcx,%rax
|
||||
call chacha20_permute
|
||||
|
||||
# o0 = i0 ^ (x0 + s0)
|
||||
paddd %xmm8,%xmm0
|
||||
cmp $0x10,%rax
|
||||
|
|
@ -156,6 +167,7 @@ ENTRY(chacha20_block_xor_ssse3)
|
|||
movdqu %xmm0,0x30(%rsi)
|
||||
|
||||
.Ldone:
|
||||
FRAME_END
|
||||
ret
|
||||
|
||||
.Lxorpart:
|
||||
|
|
@ -189,6 +201,25 @@ ENTRY(chacha20_block_xor_ssse3)
|
|||
|
||||
ENDPROC(chacha20_block_xor_ssse3)
|
||||
|
||||
ENTRY(hchacha20_block_ssse3)
|
||||
# %rdi: Input state matrix, s
|
||||
# %rsi: output (8 32-bit words)
|
||||
FRAME_BEGIN
|
||||
|
||||
movdqa 0x00(%rdi),%xmm0
|
||||
movdqa 0x10(%rdi),%xmm1
|
||||
movdqa 0x20(%rdi),%xmm2
|
||||
movdqa 0x30(%rdi),%xmm3
|
||||
|
||||
call chacha20_permute
|
||||
|
||||
movdqu %xmm0,0x00(%rsi)
|
||||
movdqu %xmm3,0x10(%rsi)
|
||||
|
||||
FRAME_END
|
||||
ret
|
||||
ENDPROC(hchacha20_block_ssse3)
|
||||
|
||||
ENTRY(chacha20_4block_xor_ssse3)
|
||||
# %rdi: Input state matrix, s
|
||||
# %rsi: up to 4 data blocks output, o
|
||||
|
|
|
|||
|
|
@ -23,6 +23,7 @@ asmlinkage void chacha20_block_xor_ssse3(u32 *state, u8 *dst, const u8 *src,
|
|||
unsigned int len);
|
||||
asmlinkage void chacha20_4block_xor_ssse3(u32 *state, u8 *dst, const u8 *src,
|
||||
unsigned int len);
|
||||
asmlinkage void hchacha20_block_ssse3(const u32 *state, u32 *out);
|
||||
#ifdef CONFIG_AS_AVX2
|
||||
asmlinkage void chacha20_2block_xor_avx2(u32 *state, u8 *dst, const u8 *src,
|
||||
unsigned int len);
|
||||
|
|
@ -121,10 +122,9 @@ static void chacha20_dosimd(u32 *state, u8 *dst, const u8 *src,
|
|||
}
|
||||
}
|
||||
|
||||
static int chacha20_simd(struct skcipher_request *req)
|
||||
static int chacha20_simd_stream_xor(struct skcipher_request *req,
|
||||
struct chacha_ctx *ctx, u8 *iv)
|
||||
{
|
||||
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
|
||||
struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm);
|
||||
u32 *state, state_buf[16 + 2] __aligned(8);
|
||||
struct skcipher_walk walk;
|
||||
int err;
|
||||
|
|
@ -132,14 +132,9 @@ static int chacha20_simd(struct skcipher_request *req)
|
|||
BUILD_BUG_ON(CHACHA20_STATE_ALIGN != 16);
|
||||
state = PTR_ALIGN(state_buf + 0, CHACHA20_STATE_ALIGN);
|
||||
|
||||
if (req->cryptlen <= CHACHA_BLOCK_SIZE || !may_use_simd())
|
||||
return crypto_chacha_crypt(req);
|
||||
|
||||
err = skcipher_walk_virt(&walk, req, true);
|
||||
|
||||
crypto_chacha_init(state, ctx, walk.iv);
|
||||
|
||||
kernel_fpu_begin();
|
||||
crypto_chacha_init(state, ctx, iv);
|
||||
|
||||
while (walk.nbytes > 0) {
|
||||
unsigned int nbytes = walk.nbytes;
|
||||
|
|
@ -153,26 +148,85 @@ static int chacha20_simd(struct skcipher_request *req)
|
|||
err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
|
||||
}
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
static int chacha20_simd(struct skcipher_request *req)
|
||||
{
|
||||
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
|
||||
struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm);
|
||||
int err;
|
||||
|
||||
if (req->cryptlen <= CHACHA_BLOCK_SIZE || !irq_fpu_usable())
|
||||
return crypto_chacha_crypt(req);
|
||||
|
||||
kernel_fpu_begin();
|
||||
err = chacha20_simd_stream_xor(req, ctx, req->iv);
|
||||
kernel_fpu_end();
|
||||
return err;
|
||||
}
|
||||
|
||||
static int xchacha20_simd(struct skcipher_request *req)
|
||||
{
|
||||
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
|
||||
struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm);
|
||||
struct chacha_ctx subctx;
|
||||
u32 *state, state_buf[16 + 2] __aligned(8);
|
||||
u8 real_iv[16];
|
||||
int err;
|
||||
|
||||
if (req->cryptlen <= CHACHA_BLOCK_SIZE || !irq_fpu_usable())
|
||||
return crypto_xchacha_crypt(req);
|
||||
|
||||
BUILD_BUG_ON(CHACHA20_STATE_ALIGN != 16);
|
||||
state = PTR_ALIGN(state_buf + 0, CHACHA20_STATE_ALIGN);
|
||||
crypto_chacha_init(state, ctx, req->iv);
|
||||
|
||||
kernel_fpu_begin();
|
||||
|
||||
hchacha20_block_ssse3(state, subctx.key);
|
||||
|
||||
memcpy(&real_iv[0], req->iv + 24, 8);
|
||||
memcpy(&real_iv[8], req->iv + 16, 8);
|
||||
err = chacha20_simd_stream_xor(req, &subctx, real_iv);
|
||||
|
||||
kernel_fpu_end();
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
static struct skcipher_alg alg = {
|
||||
.base.cra_name = "chacha20",
|
||||
.base.cra_driver_name = "chacha20-simd",
|
||||
.base.cra_priority = 300,
|
||||
.base.cra_blocksize = 1,
|
||||
.base.cra_ctxsize = sizeof(struct chacha_ctx),
|
||||
.base.cra_module = THIS_MODULE,
|
||||
static struct skcipher_alg algs[] = {
|
||||
{
|
||||
.base.cra_name = "chacha20",
|
||||
.base.cra_driver_name = "chacha20-simd",
|
||||
.base.cra_priority = 300,
|
||||
.base.cra_blocksize = 1,
|
||||
.base.cra_ctxsize = sizeof(struct chacha_ctx),
|
||||
.base.cra_module = THIS_MODULE,
|
||||
|
||||
.min_keysize = CHACHA_KEY_SIZE,
|
||||
.max_keysize = CHACHA_KEY_SIZE,
|
||||
.ivsize = CHACHA_IV_SIZE,
|
||||
.chunksize = CHACHA_BLOCK_SIZE,
|
||||
.setkey = crypto_chacha20_setkey,
|
||||
.encrypt = chacha20_simd,
|
||||
.decrypt = chacha20_simd,
|
||||
.min_keysize = CHACHA_KEY_SIZE,
|
||||
.max_keysize = CHACHA_KEY_SIZE,
|
||||
.ivsize = CHACHA_IV_SIZE,
|
||||
.chunksize = CHACHA_BLOCK_SIZE,
|
||||
.setkey = crypto_chacha20_setkey,
|
||||
.encrypt = chacha20_simd,
|
||||
.decrypt = chacha20_simd,
|
||||
}, {
|
||||
.base.cra_name = "xchacha20",
|
||||
.base.cra_driver_name = "xchacha20-simd",
|
||||
.base.cra_priority = 300,
|
||||
.base.cra_blocksize = 1,
|
||||
.base.cra_ctxsize = sizeof(struct chacha_ctx),
|
||||
.base.cra_module = THIS_MODULE,
|
||||
|
||||
.min_keysize = CHACHA_KEY_SIZE,
|
||||
.max_keysize = CHACHA_KEY_SIZE,
|
||||
.ivsize = XCHACHA_IV_SIZE,
|
||||
.chunksize = CHACHA_BLOCK_SIZE,
|
||||
.setkey = crypto_chacha20_setkey,
|
||||
.encrypt = xchacha20_simd,
|
||||
.decrypt = xchacha20_simd,
|
||||
},
|
||||
};
|
||||
|
||||
static int __init chacha20_simd_mod_init(void)
|
||||
|
|
@ -190,12 +244,12 @@ static int __init chacha20_simd_mod_init(void)
|
|||
boot_cpu_has(X86_FEATURE_AVX512BW); /* kmovq */
|
||||
#endif
|
||||
#endif
|
||||
return crypto_register_skcipher(&alg);
|
||||
return crypto_register_skciphers(algs, ARRAY_SIZE(algs));
|
||||
}
|
||||
|
||||
static void __exit chacha20_simd_mod_fini(void)
|
||||
{
|
||||
crypto_unregister_skcipher(&alg);
|
||||
crypto_unregister_skciphers(algs, ARRAY_SIZE(algs));
|
||||
}
|
||||
|
||||
module_init(chacha20_simd_mod_init);
|
||||
|
|
@ -206,3 +260,5 @@ MODULE_AUTHOR("Martin Willi <martin@strongswan.org>");
|
|||
MODULE_DESCRIPTION("chacha20 cipher algorithm, SIMD accelerated");
|
||||
MODULE_ALIAS_CRYPTO("chacha20");
|
||||
MODULE_ALIAS_CRYPTO("chacha20-simd");
|
||||
MODULE_ALIAS_CRYPTO("xchacha20");
|
||||
MODULE_ALIAS_CRYPTO("xchacha20-simd");
|
||||
|
|
|
|||
|
|
@ -1468,19 +1468,13 @@ config CRYPTO_CHACHA20
|
|||
in some performance-sensitive scenarios.
|
||||
|
||||
config CRYPTO_CHACHA20_X86_64
|
||||
tristate "ChaCha20 cipher algorithm (x86_64/SSSE3/AVX2)"
|
||||
tristate "ChaCha stream cipher algorithms (x86_64/SSSE3/AVX2/AVX-512VL)"
|
||||
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>
|
||||
SSSE3, AVX2, and AVX-512VL optimized implementations of the ChaCha20
|
||||
and XChaCha20 stream ciphers.
|
||||
|
||||
config CRYPTO_SEED
|
||||
tristate "SEED cipher algorithm"
|
||||
|
|
|
|||
Loading…
Reference in New Issue