diff mbox series

[RFC,v2,10/12] crypto: arm/nhpoly1305 - add NEON-accelerated NHPoly1305

Message ID 20181015175424.97147-11-ebiggers@kernel.org (mailing list archive)
State RFC
Delegated to: Herbert Xu
Headers show
Series crypto: Adiantum support | expand

Commit Message

Eric Biggers Oct. 15, 2018, 5:54 p.m. UTC
From: Eric Biggers <ebiggers@google.com>

Add an ARM NEON implementation of NHPoly1305, an ε-almost-∆-universal
hash function used in the Adiantum encryption mode.  For now, only the
NH portion is actually NEON-accelerated; the Poly1305 part is less
performance-critical so is just implemented in C.

Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 arch/arm/crypto/Kconfig                |   5 ++
 arch/arm/crypto/Makefile               |   2 +
 arch/arm/crypto/nh-neon-core.S         | 116 +++++++++++++++++++++++++
 arch/arm/crypto/nhpoly1305-neon-glue.c |  78 +++++++++++++++++
 4 files changed, 201 insertions(+)
 create mode 100644 arch/arm/crypto/nh-neon-core.S
 create mode 100644 arch/arm/crypto/nhpoly1305-neon-glue.c

Comments

Ard Biesheuvel Oct. 20, 2018, 4:12 a.m. UTC | #1
On 16 October 2018 at 01:54, Eric Biggers <ebiggers@kernel.org> wrote:
> From: Eric Biggers <ebiggers@google.com>
>
> Add an ARM NEON implementation of NHPoly1305, an ε-almost-∆-universal
> hash function used in the Adiantum encryption mode.  For now, only the
> NH portion is actually NEON-accelerated; the Poly1305 part is less
> performance-critical so is just implemented in C.
>
> Signed-off-by: Eric Biggers <ebiggers@google.com>
> ---
>  arch/arm/crypto/Kconfig                |   5 ++
>  arch/arm/crypto/Makefile               |   2 +
>  arch/arm/crypto/nh-neon-core.S         | 116 +++++++++++++++++++++++++
>  arch/arm/crypto/nhpoly1305-neon-glue.c |  78 +++++++++++++++++
>  4 files changed, 201 insertions(+)
>  create mode 100644 arch/arm/crypto/nh-neon-core.S
>  create mode 100644 arch/arm/crypto/nhpoly1305-neon-glue.c
>
> diff --git a/arch/arm/crypto/Kconfig b/arch/arm/crypto/Kconfig
> index cc932d9bba561..458562a34aabe 100644
> --- a/arch/arm/crypto/Kconfig
> +++ b/arch/arm/crypto/Kconfig
> @@ -122,4 +122,9 @@ config CRYPTO_CHACHA20_NEON
>         select CRYPTO_BLKCIPHER
>         select CRYPTO_CHACHA20
>
> +config CRYPTO_NHPOLY1305_NEON
> +       tristate "NEON accelerated NHPoly1305 hash function (for Adiantum)"
> +       depends on KERNEL_MODE_NEON
> +       select CRYPTO_NHPOLY1305
> +
>  endif
> diff --git a/arch/arm/crypto/Makefile b/arch/arm/crypto/Makefile
> index 005482ff95047..b65d6bfab8e6b 100644
> --- a/arch/arm/crypto/Makefile
> +++ b/arch/arm/crypto/Makefile
> @@ -10,6 +10,7 @@ obj-$(CONFIG_CRYPTO_SHA1_ARM_NEON) += sha1-arm-neon.o
>  obj-$(CONFIG_CRYPTO_SHA256_ARM) += sha256-arm.o
>  obj-$(CONFIG_CRYPTO_SHA512_ARM) += sha512-arm.o
>  obj-$(CONFIG_CRYPTO_CHACHA20_NEON) += chacha-neon.o
> +obj-$(CONFIG_CRYPTO_NHPOLY1305_NEON) += nhpoly1305-neon.o
>
>  ce-obj-$(CONFIG_CRYPTO_AES_ARM_CE) += aes-arm-ce.o
>  ce-obj-$(CONFIG_CRYPTO_SHA1_ARM_CE) += sha1-arm-ce.o
> @@ -53,6 +54,7 @@ ghash-arm-ce-y        := ghash-ce-core.o ghash-ce-glue.o
>  crct10dif-arm-ce-y     := crct10dif-ce-core.o crct10dif-ce-glue.o
>  crc32-arm-ce-y:= crc32-ce-core.o crc32-ce-glue.o
>  chacha-neon-y := chacha-neon-core.o chacha-neon-glue.o
> +nhpoly1305-neon-y := nh-neon-core.o nhpoly1305-neon-glue.o
>
>  ifdef REGENERATE_ARM_CRYPTO
>  quiet_cmd_perl = PERL    $@
> diff --git a/arch/arm/crypto/nh-neon-core.S b/arch/arm/crypto/nh-neon-core.S
> new file mode 100644
> index 0000000000000..434d80ab531c2
> --- /dev/null
> +++ b/arch/arm/crypto/nh-neon-core.S
> @@ -0,0 +1,116 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * NH - ε-almost-universal hash function, NEON accelerated version
> + *
> + * Copyright 2018 Google LLC
> + *
> + * Author: Eric Biggers <ebiggers@google.com>
> + */
> +
> +#include <linux/linkage.h>
> +
> +       .text
> +       .fpu            neon
> +
> +       KEY             .req    r0
> +       MESSAGE         .req    r1
> +       MESSAGE_LEN     .req    r2
> +       HASH            .req    r3
> +
> +       PASS0_SUMS      .req    q0
> +       PASS0_SUM_A     .req    d0
> +       PASS0_SUM_B     .req    d1
> +       PASS1_SUMS      .req    q1
> +       PASS1_SUM_A     .req    d2
> +       PASS1_SUM_B     .req    d3
> +       PASS2_SUMS      .req    q2
> +       PASS2_SUM_A     .req    d4
> +       PASS2_SUM_B     .req    d5
> +       PASS3_SUMS      .req    q3
> +       PASS3_SUM_A     .req    d6
> +       PASS3_SUM_B     .req    d7
> +       K0              .req    q4
> +       K1              .req    q5
> +       K2              .req    q6
> +       K3              .req    q7
> +       T0              .req    q8
> +       T0_L            .req    d16
> +       T0_H            .req    d17
> +       T1              .req    q9
> +       T1_L            .req    d18
> +       T1_H            .req    d19
> +       T2              .req    q10
> +       T2_L            .req    d20
> +       T2_H            .req    d21
> +       T3              .req    q11
> +       T3_L            .req    d22
> +       T3_H            .req    d23
> +
> +.macro _nh_stride      k0, k1, k2, k3
> +
> +       // Load next message stride
> +       vld1.8          {T3}, [MESSAGE]!
> +
> +       // Load next key stride
> +       vld1.32         {\k3}, [KEY]!
> +
> +       // Add message words to key words
> +       vadd.u32        T0, T3, \k0
> +       vadd.u32        T1, T3, \k1
> +       vadd.u32        T2, T3, \k2
> +       vadd.u32        T3, T3, \k3
> +
> +       // Multiply 32x32 => 64 and accumulate
> +       vmlal.u32       PASS0_SUMS, T0_L, T0_H
> +       vmlal.u32       PASS1_SUMS, T1_L, T1_H
> +       vmlal.u32       PASS2_SUMS, T2_L, T2_H
> +       vmlal.u32       PASS3_SUMS, T3_L, T3_H
> +.endm
> +

Since we seem to have some spare NEON registers: would it help to have
a double round version of this macro?

> +/*
> + * void nh_neon(const u32 *key, const u8 *message, size_t message_len,
> + *             u8 hash[NH_HASH_BYTES])
> + *
> + * It's guaranteed that message_len % 16 == 0.
> + */
> +ENTRY(nh_neon)
> +
> +       vld1.32         {K0,K1}, [KEY]!
> +         vmov.u64      PASS0_SUMS, #0
> +         vmov.u64      PASS1_SUMS, #0
> +       vld1.32         {K2}, [KEY]!
> +         vmov.u64      PASS2_SUMS, #0
> +         vmov.u64      PASS3_SUMS, #0
> +
> +       subs            MESSAGE_LEN, MESSAGE_LEN, #64
> +       blt             .Lloop4_done
> +.Lloop4:
> +       _nh_stride      K0, K1, K2, K3
> +       _nh_stride      K1, K2, K3, K0
> +       _nh_stride      K2, K3, K0, K1
> +       _nh_stride      K3, K0, K1, K2
> +       subs            MESSAGE_LEN, MESSAGE_LEN, #64
> +       bge             .Lloop4
> +
> +.Lloop4_done:
> +       ands            MESSAGE_LEN, MESSAGE_LEN, #63
> +       beq             .Ldone
> +       _nh_stride      K0, K1, K2, K3
> +
> +       subs            MESSAGE_LEN, MESSAGE_LEN, #16
> +       beq             .Ldone
> +       _nh_stride      K1, K2, K3, K0
> +
> +       subs            MESSAGE_LEN, MESSAGE_LEN, #16
> +       beq             .Ldone
> +       _nh_stride      K2, K3, K0, K1
> +
> +.Ldone:
> +       // Sum the accumulators for each pass, then store the sums to 'hash'
> +       vadd.u64        T0_L, PASS0_SUM_A, PASS0_SUM_B
> +       vadd.u64        T0_H, PASS1_SUM_A, PASS1_SUM_B
> +       vadd.u64        T1_L, PASS2_SUM_A, PASS2_SUM_B
> +       vadd.u64        T1_H, PASS3_SUM_A, PASS3_SUM_B
> +       vst1.8          {T0-T1}, [HASH]
> +       bx              lr
> +ENDPROC(nh_neon)
> diff --git a/arch/arm/crypto/nhpoly1305-neon-glue.c b/arch/arm/crypto/nhpoly1305-neon-glue.c
> new file mode 100644
> index 0000000000000..df48a00f4c50f
> --- /dev/null
> +++ b/arch/arm/crypto/nhpoly1305-neon-glue.c
> @@ -0,0 +1,78 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * NHPoly1305 - ε-almost-∆-universal hash function for Adiantum
> + * (NEON accelerated version)
> + *
> + * Copyright 2018 Google LLC
> + */
> +
> +#include <asm/neon.h>
> +#include <asm/simd.h>
> +#include <crypto/internal/hash.h>
> +#include <crypto/nhpoly1305.h>
> +#include <linux/module.h>
> +
> +asmlinkage void nh_neon(const u32 *key, const u8 *message, size_t message_len,
> +                       u8 hash[NH_HASH_BYTES]);
> +
> +static void _nh_neon(const u32 *key, const u8 *message, size_t message_len,
> +                    __le64 hash[NH_NUM_PASSES])
> +{
> +       nh_neon(key, message, message_len, (u8 *)hash);
> +}
> +

Why do we need this function?

> +static int nhpoly1305_neon_update(struct shash_desc *desc,
> +                                 const u8 *src, unsigned int srclen)
> +{
> +       if (srclen < 64 || !may_use_simd())
> +               return crypto_nhpoly1305_update(desc, src, srclen);
> +
> +       do {
> +               unsigned int n = min_t(unsigned int, srclen, PAGE_SIZE);
> +
> +               kernel_neon_begin();
> +               crypto_nhpoly1305_update_helper(desc, src, n, _nh_neon);
> +               kernel_neon_end();
> +               src += n;
> +               srclen -= n;
> +       } while (srclen);
> +       return 0;
> +}
> +
> +static struct shash_alg nhpoly1305_alg = {
> +       .digestsize     = POLY1305_DIGEST_SIZE,
> +       .init           = crypto_nhpoly1305_init,
> +       .update         = nhpoly1305_neon_update,
> +       .final          = crypto_nhpoly1305_final,
> +       .setkey         = crypto_nhpoly1305_setkey,
> +       .descsize       = sizeof(struct nhpoly1305_state),
> +       .base           = {
> +               .cra_name               = "nhpoly1305",
> +               .cra_driver_name        = "nhpoly1305-neon",
> +               .cra_priority           = 200,
> +               .cra_ctxsize            = sizeof(struct nhpoly1305_key),
> +               .cra_module             = THIS_MODULE,
> +       },

Can we use .base.xxx please?

> +};
> +
> +static int __init nhpoly1305_mod_init(void)
> +{
> +       if (!(elf_hwcap & HWCAP_NEON))
> +               return -ENODEV;
> +
> +       return crypto_register_shash(&nhpoly1305_alg);
> +}
> +
> +static void __exit nhpoly1305_mod_exit(void)
> +{
> +       crypto_unregister_shash(&nhpoly1305_alg);
> +}
> +
> +module_init(nhpoly1305_mod_init);
> +module_exit(nhpoly1305_mod_exit);
> +
> +MODULE_DESCRIPTION("NHPoly1305 ε-almost-∆-universal hash function (NEON-accelerated)");
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Eric Biggers <ebiggers@google.com>");
> +MODULE_ALIAS_CRYPTO("nhpoly1305");
> +MODULE_ALIAS_CRYPTO("nhpoly1305-neon");
> --
> 2.19.1.331.ge82ca0e54c-goog
>
Eric Biggers Oct. 20, 2018, 5:51 a.m. UTC | #2
On Sat, Oct 20, 2018 at 12:12:56PM +0800, Ard Biesheuvel wrote:
> On 16 October 2018 at 01:54, Eric Biggers <ebiggers@kernel.org> wrote:
> > From: Eric Biggers <ebiggers@google.com>
> >
> > Add an ARM NEON implementation of NHPoly1305, an ε-almost-∆-universal
> > hash function used in the Adiantum encryption mode.  For now, only the
> > NH portion is actually NEON-accelerated; the Poly1305 part is less
> > performance-critical so is just implemented in C.
> >
> > Signed-off-by: Eric Biggers <ebiggers@google.com>
> > ---
> >  arch/arm/crypto/Kconfig                |   5 ++
> >  arch/arm/crypto/Makefile               |   2 +
> >  arch/arm/crypto/nh-neon-core.S         | 116 +++++++++++++++++++++++++
> >  arch/arm/crypto/nhpoly1305-neon-glue.c |  78 +++++++++++++++++
> >  4 files changed, 201 insertions(+)
> >  create mode 100644 arch/arm/crypto/nh-neon-core.S
> >  create mode 100644 arch/arm/crypto/nhpoly1305-neon-glue.c
> >
> > diff --git a/arch/arm/crypto/Kconfig b/arch/arm/crypto/Kconfig
> > index cc932d9bba561..458562a34aabe 100644
> > --- a/arch/arm/crypto/Kconfig
> > +++ b/arch/arm/crypto/Kconfig
> > @@ -122,4 +122,9 @@ config CRYPTO_CHACHA20_NEON
> >         select CRYPTO_BLKCIPHER
> >         select CRYPTO_CHACHA20
> >
> > +config CRYPTO_NHPOLY1305_NEON
> > +       tristate "NEON accelerated NHPoly1305 hash function (for Adiantum)"
> > +       depends on KERNEL_MODE_NEON
> > +       select CRYPTO_NHPOLY1305
> > +
> >  endif
> > diff --git a/arch/arm/crypto/Makefile b/arch/arm/crypto/Makefile
> > index 005482ff95047..b65d6bfab8e6b 100644
> > --- a/arch/arm/crypto/Makefile
> > +++ b/arch/arm/crypto/Makefile
> > @@ -10,6 +10,7 @@ obj-$(CONFIG_CRYPTO_SHA1_ARM_NEON) += sha1-arm-neon.o
> >  obj-$(CONFIG_CRYPTO_SHA256_ARM) += sha256-arm.o
> >  obj-$(CONFIG_CRYPTO_SHA512_ARM) += sha512-arm.o
> >  obj-$(CONFIG_CRYPTO_CHACHA20_NEON) += chacha-neon.o
> > +obj-$(CONFIG_CRYPTO_NHPOLY1305_NEON) += nhpoly1305-neon.o
> >
> >  ce-obj-$(CONFIG_CRYPTO_AES_ARM_CE) += aes-arm-ce.o
> >  ce-obj-$(CONFIG_CRYPTO_SHA1_ARM_CE) += sha1-arm-ce.o
> > @@ -53,6 +54,7 @@ ghash-arm-ce-y        := ghash-ce-core.o ghash-ce-glue.o
> >  crct10dif-arm-ce-y     := crct10dif-ce-core.o crct10dif-ce-glue.o
> >  crc32-arm-ce-y:= crc32-ce-core.o crc32-ce-glue.o
> >  chacha-neon-y := chacha-neon-core.o chacha-neon-glue.o
> > +nhpoly1305-neon-y := nh-neon-core.o nhpoly1305-neon-glue.o
> >
> >  ifdef REGENERATE_ARM_CRYPTO
> >  quiet_cmd_perl = PERL    $@
> > diff --git a/arch/arm/crypto/nh-neon-core.S b/arch/arm/crypto/nh-neon-core.S
> > new file mode 100644
> > index 0000000000000..434d80ab531c2
> > --- /dev/null
> > +++ b/arch/arm/crypto/nh-neon-core.S
> > @@ -0,0 +1,116 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * NH - ε-almost-universal hash function, NEON accelerated version
> > + *
> > + * Copyright 2018 Google LLC
> > + *
> > + * Author: Eric Biggers <ebiggers@google.com>
> > + */
> > +
> > +#include <linux/linkage.h>
> > +
> > +       .text
> > +       .fpu            neon
> > +
> > +       KEY             .req    r0
> > +       MESSAGE         .req    r1
> > +       MESSAGE_LEN     .req    r2
> > +       HASH            .req    r3
> > +
> > +       PASS0_SUMS      .req    q0
> > +       PASS0_SUM_A     .req    d0
> > +       PASS0_SUM_B     .req    d1
> > +       PASS1_SUMS      .req    q1
> > +       PASS1_SUM_A     .req    d2
> > +       PASS1_SUM_B     .req    d3
> > +       PASS2_SUMS      .req    q2
> > +       PASS2_SUM_A     .req    d4
> > +       PASS2_SUM_B     .req    d5
> > +       PASS3_SUMS      .req    q3
> > +       PASS3_SUM_A     .req    d6
> > +       PASS3_SUM_B     .req    d7
> > +       K0              .req    q4
> > +       K1              .req    q5
> > +       K2              .req    q6
> > +       K3              .req    q7
> > +       T0              .req    q8
> > +       T0_L            .req    d16
> > +       T0_H            .req    d17
> > +       T1              .req    q9
> > +       T1_L            .req    d18
> > +       T1_H            .req    d19
> > +       T2              .req    q10
> > +       T2_L            .req    d20
> > +       T2_H            .req    d21
> > +       T3              .req    q11
> > +       T3_L            .req    d22
> > +       T3_H            .req    d23
> > +
> > +.macro _nh_stride      k0, k1, k2, k3
> > +
> > +       // Load next message stride
> > +       vld1.8          {T3}, [MESSAGE]!
> > +
> > +       // Load next key stride
> > +       vld1.32         {\k3}, [KEY]!
> > +
> > +       // Add message words to key words
> > +       vadd.u32        T0, T3, \k0
> > +       vadd.u32        T1, T3, \k1
> > +       vadd.u32        T2, T3, \k2
> > +       vadd.u32        T3, T3, \k3
> > +
> > +       // Multiply 32x32 => 64 and accumulate
> > +       vmlal.u32       PASS0_SUMS, T0_L, T0_H
> > +       vmlal.u32       PASS1_SUMS, T1_L, T1_H
> > +       vmlal.u32       PASS2_SUMS, T2_L, T2_H
> > +       vmlal.u32       PASS3_SUMS, T3_L, T3_H
> > +.endm
> > +
> 
> Since we seem to have some spare NEON registers: would it help to have
> a double round version of this macro?
> 

It helps a little bit, but not much.  The loads are the only part that can be
optimized further.  I think I'd rather have the shorter + simpler version,
unless the loads can be optimized significantly more on other processors.

Also, originally I had it loading the key and message for the next stride while
doing the current one, but that didn't seem worthwhile either.

> > +/*
> > + * void nh_neon(const u32 *key, const u8 *message, size_t message_len,
> > + *             u8 hash[NH_HASH_BYTES])
> > + *
> > + * It's guaranteed that message_len % 16 == 0.
> > + */
> > +ENTRY(nh_neon)
> > +
> > +       vld1.32         {K0,K1}, [KEY]!
> > +         vmov.u64      PASS0_SUMS, #0
> > +         vmov.u64      PASS1_SUMS, #0
> > +       vld1.32         {K2}, [KEY]!
> > +         vmov.u64      PASS2_SUMS, #0
> > +         vmov.u64      PASS3_SUMS, #0
> > +
> > +       subs            MESSAGE_LEN, MESSAGE_LEN, #64
> > +       blt             .Lloop4_done
> > +.Lloop4:
> > +       _nh_stride      K0, K1, K2, K3
> > +       _nh_stride      K1, K2, K3, K0
> > +       _nh_stride      K2, K3, K0, K1
> > +       _nh_stride      K3, K0, K1, K2
> > +       subs            MESSAGE_LEN, MESSAGE_LEN, #64
> > +       bge             .Lloop4
> > +
> > +.Lloop4_done:
> > +       ands            MESSAGE_LEN, MESSAGE_LEN, #63
> > +       beq             .Ldone
> > +       _nh_stride      K0, K1, K2, K3
> > +
> > +       subs            MESSAGE_LEN, MESSAGE_LEN, #16
> > +       beq             .Ldone
> > +       _nh_stride      K1, K2, K3, K0
> > +
> > +       subs            MESSAGE_LEN, MESSAGE_LEN, #16
> > +       beq             .Ldone
> > +       _nh_stride      K2, K3, K0, K1
> > +
> > +.Ldone:
> > +       // Sum the accumulators for each pass, then store the sums to 'hash'
> > +       vadd.u64        T0_L, PASS0_SUM_A, PASS0_SUM_B
> > +       vadd.u64        T0_H, PASS1_SUM_A, PASS1_SUM_B
> > +       vadd.u64        T1_L, PASS2_SUM_A, PASS2_SUM_B
> > +       vadd.u64        T1_H, PASS3_SUM_A, PASS3_SUM_B
> > +       vst1.8          {T0-T1}, [HASH]
> > +       bx              lr
> > +ENDPROC(nh_neon)
> > diff --git a/arch/arm/crypto/nhpoly1305-neon-glue.c b/arch/arm/crypto/nhpoly1305-neon-glue.c
> > new file mode 100644
> > index 0000000000000..df48a00f4c50f
> > --- /dev/null
> > +++ b/arch/arm/crypto/nhpoly1305-neon-glue.c
> > @@ -0,0 +1,78 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * NHPoly1305 - ε-almost-∆-universal hash function for Adiantum
> > + * (NEON accelerated version)
> > + *
> > + * Copyright 2018 Google LLC
> > + */
> > +
> > +#include <asm/neon.h>
> > +#include <asm/simd.h>
> > +#include <crypto/internal/hash.h>
> > +#include <crypto/nhpoly1305.h>
> > +#include <linux/module.h>
> > +
> > +asmlinkage void nh_neon(const u32 *key, const u8 *message, size_t message_len,
> > +                       u8 hash[NH_HASH_BYTES]);
> > +
> > +static void _nh_neon(const u32 *key, const u8 *message, size_t message_len,
> > +                    __le64 hash[NH_NUM_PASSES])
> > +{
> > +       nh_neon(key, message, message_len, (u8 *)hash);
> > +}
> > +
> 
> Why do we need this function?
> 

For now it's not needed so I should probably just remove it, but it seems likely
that indirect calls to assembly functions in the kernel will be going away in
order to add support for CFI (control flow integrity).  The android-4.9 and
android-4.14 kernels support CFI on arm64, so you might notice that some of the
arm64 crypto code had to be patched for this reason.

- Eric
Ard Biesheuvel Oct. 20, 2018, 3 p.m. UTC | #3
On 20 October 2018 at 13:51, Eric Biggers <ebiggers@kernel.org> wrote:
> On Sat, Oct 20, 2018 at 12:12:56PM +0800, Ard Biesheuvel wrote:
>> On 16 October 2018 at 01:54, Eric Biggers <ebiggers@kernel.org> wrote:
>> > From: Eric Biggers <ebiggers@google.com>
>> >
>> > Add an ARM NEON implementation of NHPoly1305, an ε-almost-∆-universal
>> > hash function used in the Adiantum encryption mode.  For now, only the
>> > NH portion is actually NEON-accelerated; the Poly1305 part is less
>> > performance-critical so is just implemented in C.
>> >
>> > Signed-off-by: Eric Biggers <ebiggers@google.com>
>> > ---
>> >  arch/arm/crypto/Kconfig                |   5 ++
>> >  arch/arm/crypto/Makefile               |   2 +
>> >  arch/arm/crypto/nh-neon-core.S         | 116 +++++++++++++++++++++++++
>> >  arch/arm/crypto/nhpoly1305-neon-glue.c |  78 +++++++++++++++++
>> >  4 files changed, 201 insertions(+)
>> >  create mode 100644 arch/arm/crypto/nh-neon-core.S
>> >  create mode 100644 arch/arm/crypto/nhpoly1305-neon-glue.c
>> >
>> > diff --git a/arch/arm/crypto/Kconfig b/arch/arm/crypto/Kconfig
>> > index cc932d9bba561..458562a34aabe 100644
>> > --- a/arch/arm/crypto/Kconfig
>> > +++ b/arch/arm/crypto/Kconfig
>> > @@ -122,4 +122,9 @@ config CRYPTO_CHACHA20_NEON
>> >         select CRYPTO_BLKCIPHER
>> >         select CRYPTO_CHACHA20
>> >
>> > +config CRYPTO_NHPOLY1305_NEON
>> > +       tristate "NEON accelerated NHPoly1305 hash function (for Adiantum)"
>> > +       depends on KERNEL_MODE_NEON
>> > +       select CRYPTO_NHPOLY1305
>> > +
>> >  endif
>> > diff --git a/arch/arm/crypto/Makefile b/arch/arm/crypto/Makefile
>> > index 005482ff95047..b65d6bfab8e6b 100644
>> > --- a/arch/arm/crypto/Makefile
>> > +++ b/arch/arm/crypto/Makefile
>> > @@ -10,6 +10,7 @@ obj-$(CONFIG_CRYPTO_SHA1_ARM_NEON) += sha1-arm-neon.o
>> >  obj-$(CONFIG_CRYPTO_SHA256_ARM) += sha256-arm.o
>> >  obj-$(CONFIG_CRYPTO_SHA512_ARM) += sha512-arm.o
>> >  obj-$(CONFIG_CRYPTO_CHACHA20_NEON) += chacha-neon.o
>> > +obj-$(CONFIG_CRYPTO_NHPOLY1305_NEON) += nhpoly1305-neon.o
>> >
>> >  ce-obj-$(CONFIG_CRYPTO_AES_ARM_CE) += aes-arm-ce.o
>> >  ce-obj-$(CONFIG_CRYPTO_SHA1_ARM_CE) += sha1-arm-ce.o
>> > @@ -53,6 +54,7 @@ ghash-arm-ce-y        := ghash-ce-core.o ghash-ce-glue.o
>> >  crct10dif-arm-ce-y     := crct10dif-ce-core.o crct10dif-ce-glue.o
>> >  crc32-arm-ce-y:= crc32-ce-core.o crc32-ce-glue.o
>> >  chacha-neon-y := chacha-neon-core.o chacha-neon-glue.o
>> > +nhpoly1305-neon-y := nh-neon-core.o nhpoly1305-neon-glue.o
>> >
>> >  ifdef REGENERATE_ARM_CRYPTO
>> >  quiet_cmd_perl = PERL    $@
>> > diff --git a/arch/arm/crypto/nh-neon-core.S b/arch/arm/crypto/nh-neon-core.S
>> > new file mode 100644
>> > index 0000000000000..434d80ab531c2
>> > --- /dev/null
>> > +++ b/arch/arm/crypto/nh-neon-core.S
>> > @@ -0,0 +1,116 @@
>> > +/* SPDX-License-Identifier: GPL-2.0 */
>> > +/*
>> > + * NH - ε-almost-universal hash function, NEON accelerated version
>> > + *
>> > + * Copyright 2018 Google LLC
>> > + *
>> > + * Author: Eric Biggers <ebiggers@google.com>
>> > + */
>> > +
>> > +#include <linux/linkage.h>
>> > +
>> > +       .text
>> > +       .fpu            neon
>> > +
>> > +       KEY             .req    r0
>> > +       MESSAGE         .req    r1
>> > +       MESSAGE_LEN     .req    r2
>> > +       HASH            .req    r3
>> > +
>> > +       PASS0_SUMS      .req    q0
>> > +       PASS0_SUM_A     .req    d0
>> > +       PASS0_SUM_B     .req    d1
>> > +       PASS1_SUMS      .req    q1
>> > +       PASS1_SUM_A     .req    d2
>> > +       PASS1_SUM_B     .req    d3
>> > +       PASS2_SUMS      .req    q2
>> > +       PASS2_SUM_A     .req    d4
>> > +       PASS2_SUM_B     .req    d5
>> > +       PASS3_SUMS      .req    q3
>> > +       PASS3_SUM_A     .req    d6
>> > +       PASS3_SUM_B     .req    d7
>> > +       K0              .req    q4
>> > +       K1              .req    q5
>> > +       K2              .req    q6
>> > +       K3              .req    q7
>> > +       T0              .req    q8
>> > +       T0_L            .req    d16
>> > +       T0_H            .req    d17
>> > +       T1              .req    q9
>> > +       T1_L            .req    d18
>> > +       T1_H            .req    d19
>> > +       T2              .req    q10
>> > +       T2_L            .req    d20
>> > +       T2_H            .req    d21
>> > +       T3              .req    q11
>> > +       T3_L            .req    d22
>> > +       T3_H            .req    d23
>> > +
>> > +.macro _nh_stride      k0, k1, k2, k3
>> > +
>> > +       // Load next message stride
>> > +       vld1.8          {T3}, [MESSAGE]!
>> > +
>> > +       // Load next key stride
>> > +       vld1.32         {\k3}, [KEY]!
>> > +
>> > +       // Add message words to key words
>> > +       vadd.u32        T0, T3, \k0
>> > +       vadd.u32        T1, T3, \k1
>> > +       vadd.u32        T2, T3, \k2
>> > +       vadd.u32        T3, T3, \k3
>> > +
>> > +       // Multiply 32x32 => 64 and accumulate
>> > +       vmlal.u32       PASS0_SUMS, T0_L, T0_H
>> > +       vmlal.u32       PASS1_SUMS, T1_L, T1_H
>> > +       vmlal.u32       PASS2_SUMS, T2_L, T2_H
>> > +       vmlal.u32       PASS3_SUMS, T3_L, T3_H
>> > +.endm
>> > +
>>
>> Since we seem to have some spare NEON registers: would it help to have
>> a double round version of this macro?
>>
>
> It helps a little bit, but not much.  The loads are the only part that can be
> optimized further.  I think I'd rather have the shorter + simpler version,
> unless the loads can be optimized significantly more on other processors.
>
> Also, originally I had it loading the key and message for the next stride while
> doing the current one, but that didn't seem worthwhile either.
>

Fair enough.

>> > +/*
>> > + * void nh_neon(const u32 *key, const u8 *message, size_t message_len,
>> > + *             u8 hash[NH_HASH_BYTES])
>> > + *
>> > + * It's guaranteed that message_len % 16 == 0.
>> > + */
>> > +ENTRY(nh_neon)
>> > +
>> > +       vld1.32         {K0,K1}, [KEY]!
>> > +         vmov.u64      PASS0_SUMS, #0
>> > +         vmov.u64      PASS1_SUMS, #0
>> > +       vld1.32         {K2}, [KEY]!
>> > +         vmov.u64      PASS2_SUMS, #0
>> > +         vmov.u64      PASS3_SUMS, #0
>> > +
>> > +       subs            MESSAGE_LEN, MESSAGE_LEN, #64
>> > +       blt             .Lloop4_done
>> > +.Lloop4:
>> > +       _nh_stride      K0, K1, K2, K3
>> > +       _nh_stride      K1, K2, K3, K0
>> > +       _nh_stride      K2, K3, K0, K1
>> > +       _nh_stride      K3, K0, K1, K2
>> > +       subs            MESSAGE_LEN, MESSAGE_LEN, #64
>> > +       bge             .Lloop4
>> > +
>> > +.Lloop4_done:
>> > +       ands            MESSAGE_LEN, MESSAGE_LEN, #63
>> > +       beq             .Ldone
>> > +       _nh_stride      K0, K1, K2, K3
>> > +
>> > +       subs            MESSAGE_LEN, MESSAGE_LEN, #16
>> > +       beq             .Ldone
>> > +       _nh_stride      K1, K2, K3, K0
>> > +
>> > +       subs            MESSAGE_LEN, MESSAGE_LEN, #16
>> > +       beq             .Ldone
>> > +       _nh_stride      K2, K3, K0, K1
>> > +
>> > +.Ldone:
>> > +       // Sum the accumulators for each pass, then store the sums to 'hash'
>> > +       vadd.u64        T0_L, PASS0_SUM_A, PASS0_SUM_B
>> > +       vadd.u64        T0_H, PASS1_SUM_A, PASS1_SUM_B
>> > +       vadd.u64        T1_L, PASS2_SUM_A, PASS2_SUM_B
>> > +       vadd.u64        T1_H, PASS3_SUM_A, PASS3_SUM_B
>> > +       vst1.8          {T0-T1}, [HASH]
>> > +       bx              lr
>> > +ENDPROC(nh_neon)
>> > diff --git a/arch/arm/crypto/nhpoly1305-neon-glue.c b/arch/arm/crypto/nhpoly1305-neon-glue.c
>> > new file mode 100644
>> > index 0000000000000..df48a00f4c50f
>> > --- /dev/null
>> > +++ b/arch/arm/crypto/nhpoly1305-neon-glue.c
>> > @@ -0,0 +1,78 @@
>> > +// SPDX-License-Identifier: GPL-2.0
>> > +/*
>> > + * NHPoly1305 - ε-almost-∆-universal hash function for Adiantum
>> > + * (NEON accelerated version)
>> > + *
>> > + * Copyright 2018 Google LLC
>> > + */
>> > +
>> > +#include <asm/neon.h>
>> > +#include <asm/simd.h>
>> > +#include <crypto/internal/hash.h>
>> > +#include <crypto/nhpoly1305.h>
>> > +#include <linux/module.h>
>> > +
>> > +asmlinkage void nh_neon(const u32 *key, const u8 *message, size_t message_len,
>> > +                       u8 hash[NH_HASH_BYTES]);
>> > +
>> > +static void _nh_neon(const u32 *key, const u8 *message, size_t message_len,
>> > +                    __le64 hash[NH_NUM_PASSES])
>> > +{
>> > +       nh_neon(key, message, message_len, (u8 *)hash);
>> > +}
>> > +
>>
>> Why do we need this function?
>>
>
> For now it's not needed so I should probably just remove it, but it seems likely
> that indirect calls to assembly functions in the kernel will be going away in
> order to add support for CFI (control flow integrity).  The android-4.9 and
> android-4.14 kernels support CFI on arm64, so you might notice that some of the
> arm64 crypto code had to be patched for this reason.
>

I didn't actually look at those kernel trees so I hadn't noticed yet.
In any case, I'd suggest that we just keep this wrapper then, but
please add a comment describing why it's there.
diff mbox series

Patch

diff --git a/arch/arm/crypto/Kconfig b/arch/arm/crypto/Kconfig
index cc932d9bba561..458562a34aabe 100644
--- a/arch/arm/crypto/Kconfig
+++ b/arch/arm/crypto/Kconfig
@@ -122,4 +122,9 @@  config CRYPTO_CHACHA20_NEON
 	select CRYPTO_BLKCIPHER
 	select CRYPTO_CHACHA20
 
+config CRYPTO_NHPOLY1305_NEON
+	tristate "NEON accelerated NHPoly1305 hash function (for Adiantum)"
+	depends on KERNEL_MODE_NEON
+	select CRYPTO_NHPOLY1305
+
 endif
diff --git a/arch/arm/crypto/Makefile b/arch/arm/crypto/Makefile
index 005482ff95047..b65d6bfab8e6b 100644
--- a/arch/arm/crypto/Makefile
+++ b/arch/arm/crypto/Makefile
@@ -10,6 +10,7 @@  obj-$(CONFIG_CRYPTO_SHA1_ARM_NEON) += sha1-arm-neon.o
 obj-$(CONFIG_CRYPTO_SHA256_ARM) += sha256-arm.o
 obj-$(CONFIG_CRYPTO_SHA512_ARM) += sha512-arm.o
 obj-$(CONFIG_CRYPTO_CHACHA20_NEON) += chacha-neon.o
+obj-$(CONFIG_CRYPTO_NHPOLY1305_NEON) += nhpoly1305-neon.o
 
 ce-obj-$(CONFIG_CRYPTO_AES_ARM_CE) += aes-arm-ce.o
 ce-obj-$(CONFIG_CRYPTO_SHA1_ARM_CE) += sha1-arm-ce.o
@@ -53,6 +54,7 @@  ghash-arm-ce-y	:= ghash-ce-core.o ghash-ce-glue.o
 crct10dif-arm-ce-y	:= crct10dif-ce-core.o crct10dif-ce-glue.o
 crc32-arm-ce-y:= crc32-ce-core.o crc32-ce-glue.o
 chacha-neon-y := chacha-neon-core.o chacha-neon-glue.o
+nhpoly1305-neon-y := nh-neon-core.o nhpoly1305-neon-glue.o
 
 ifdef REGENERATE_ARM_CRYPTO
 quiet_cmd_perl = PERL    $@
diff --git a/arch/arm/crypto/nh-neon-core.S b/arch/arm/crypto/nh-neon-core.S
new file mode 100644
index 0000000000000..434d80ab531c2
--- /dev/null
+++ b/arch/arm/crypto/nh-neon-core.S
@@ -0,0 +1,116 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * NH - ε-almost-universal hash function, NEON accelerated version
+ *
+ * Copyright 2018 Google LLC
+ *
+ * Author: Eric Biggers <ebiggers@google.com>
+ */
+
+#include <linux/linkage.h>
+
+	.text
+	.fpu		neon
+
+	KEY		.req	r0
+	MESSAGE		.req	r1
+	MESSAGE_LEN	.req	r2
+	HASH		.req	r3
+
+	PASS0_SUMS	.req	q0
+	PASS0_SUM_A	.req	d0
+	PASS0_SUM_B	.req	d1
+	PASS1_SUMS	.req	q1
+	PASS1_SUM_A	.req	d2
+	PASS1_SUM_B	.req	d3
+	PASS2_SUMS	.req	q2
+	PASS2_SUM_A	.req	d4
+	PASS2_SUM_B	.req	d5
+	PASS3_SUMS	.req	q3
+	PASS3_SUM_A	.req	d6
+	PASS3_SUM_B	.req	d7
+	K0		.req	q4
+	K1		.req	q5
+	K2		.req	q6
+	K3		.req	q7
+	T0		.req	q8
+	T0_L		.req	d16
+	T0_H		.req	d17
+	T1		.req	q9
+	T1_L		.req	d18
+	T1_H		.req	d19
+	T2		.req	q10
+	T2_L		.req	d20
+	T2_H		.req	d21
+	T3		.req	q11
+	T3_L		.req	d22
+	T3_H		.req	d23
+
+.macro _nh_stride	k0, k1, k2, k3
+
+	// Load next message stride
+	vld1.8		{T3}, [MESSAGE]!
+
+	// Load next key stride
+	vld1.32		{\k3}, [KEY]!
+
+	// Add message words to key words
+	vadd.u32	T0, T3, \k0
+	vadd.u32	T1, T3, \k1
+	vadd.u32	T2, T3, \k2
+	vadd.u32	T3, T3, \k3
+
+	// Multiply 32x32 => 64 and accumulate
+	vmlal.u32	PASS0_SUMS, T0_L, T0_H
+	vmlal.u32	PASS1_SUMS, T1_L, T1_H
+	vmlal.u32	PASS2_SUMS, T2_L, T2_H
+	vmlal.u32	PASS3_SUMS, T3_L, T3_H
+.endm
+
+/*
+ * void nh_neon(const u32 *key, const u8 *message, size_t message_len,
+ *		u8 hash[NH_HASH_BYTES])
+ *
+ * It's guaranteed that message_len % 16 == 0.
+ */
+ENTRY(nh_neon)
+
+	vld1.32		{K0,K1}, [KEY]!
+	  vmov.u64	PASS0_SUMS, #0
+	  vmov.u64	PASS1_SUMS, #0
+	vld1.32		{K2}, [KEY]!
+	  vmov.u64	PASS2_SUMS, #0
+	  vmov.u64	PASS3_SUMS, #0
+
+	subs		MESSAGE_LEN, MESSAGE_LEN, #64
+	blt		.Lloop4_done
+.Lloop4:
+	_nh_stride	K0, K1, K2, K3
+	_nh_stride	K1, K2, K3, K0
+	_nh_stride	K2, K3, K0, K1
+	_nh_stride	K3, K0, K1, K2
+	subs		MESSAGE_LEN, MESSAGE_LEN, #64
+	bge		.Lloop4
+
+.Lloop4_done:
+	ands		MESSAGE_LEN, MESSAGE_LEN, #63
+	beq		.Ldone
+	_nh_stride	K0, K1, K2, K3
+
+	subs		MESSAGE_LEN, MESSAGE_LEN, #16
+	beq		.Ldone
+	_nh_stride	K1, K2, K3, K0
+
+	subs		MESSAGE_LEN, MESSAGE_LEN, #16
+	beq		.Ldone
+	_nh_stride	K2, K3, K0, K1
+
+.Ldone:
+	// Sum the accumulators for each pass, then store the sums to 'hash'
+	vadd.u64	T0_L, PASS0_SUM_A, PASS0_SUM_B
+	vadd.u64	T0_H, PASS1_SUM_A, PASS1_SUM_B
+	vadd.u64	T1_L, PASS2_SUM_A, PASS2_SUM_B
+	vadd.u64	T1_H, PASS3_SUM_A, PASS3_SUM_B
+	vst1.8		{T0-T1}, [HASH]
+	bx		lr
+ENDPROC(nh_neon)
diff --git a/arch/arm/crypto/nhpoly1305-neon-glue.c b/arch/arm/crypto/nhpoly1305-neon-glue.c
new file mode 100644
index 0000000000000..df48a00f4c50f
--- /dev/null
+++ b/arch/arm/crypto/nhpoly1305-neon-glue.c
@@ -0,0 +1,78 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * NHPoly1305 - ε-almost-∆-universal hash function for Adiantum
+ * (NEON accelerated version)
+ *
+ * Copyright 2018 Google LLC
+ */
+
+#include <asm/neon.h>
+#include <asm/simd.h>
+#include <crypto/internal/hash.h>
+#include <crypto/nhpoly1305.h>
+#include <linux/module.h>
+
+asmlinkage void nh_neon(const u32 *key, const u8 *message, size_t message_len,
+			u8 hash[NH_HASH_BYTES]);
+
+static void _nh_neon(const u32 *key, const u8 *message, size_t message_len,
+		     __le64 hash[NH_NUM_PASSES])
+{
+	nh_neon(key, message, message_len, (u8 *)hash);
+}
+
+static int nhpoly1305_neon_update(struct shash_desc *desc,
+				  const u8 *src, unsigned int srclen)
+{
+	if (srclen < 64 || !may_use_simd())
+		return crypto_nhpoly1305_update(desc, src, srclen);
+
+	do {
+		unsigned int n = min_t(unsigned int, srclen, PAGE_SIZE);
+
+		kernel_neon_begin();
+		crypto_nhpoly1305_update_helper(desc, src, n, _nh_neon);
+		kernel_neon_end();
+		src += n;
+		srclen -= n;
+	} while (srclen);
+	return 0;
+}
+
+static struct shash_alg nhpoly1305_alg = {
+	.digestsize	= POLY1305_DIGEST_SIZE,
+	.init		= crypto_nhpoly1305_init,
+	.update		= nhpoly1305_neon_update,
+	.final		= crypto_nhpoly1305_final,
+	.setkey		= crypto_nhpoly1305_setkey,
+	.descsize	= sizeof(struct nhpoly1305_state),
+	.base		= {
+		.cra_name		= "nhpoly1305",
+		.cra_driver_name	= "nhpoly1305-neon",
+		.cra_priority		= 200,
+		.cra_ctxsize		= sizeof(struct nhpoly1305_key),
+		.cra_module		= THIS_MODULE,
+	},
+};
+
+static int __init nhpoly1305_mod_init(void)
+{
+	if (!(elf_hwcap & HWCAP_NEON))
+		return -ENODEV;
+
+	return crypto_register_shash(&nhpoly1305_alg);
+}
+
+static void __exit nhpoly1305_mod_exit(void)
+{
+	crypto_unregister_shash(&nhpoly1305_alg);
+}
+
+module_init(nhpoly1305_mod_init);
+module_exit(nhpoly1305_mod_exit);
+
+MODULE_DESCRIPTION("NHPoly1305 ε-almost-∆-universal hash function (NEON-accelerated)");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Eric Biggers <ebiggers@google.com>");
+MODULE_ALIAS_CRYPTO("nhpoly1305");
+MODULE_ALIAS_CRYPTO("nhpoly1305-neon");