From: Eric Biggers <ebiggers@xxxxxxxxxx>
Add an ARM64 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@xxxxxxxxxx>
---
arch/arm64/crypto/Kconfig | 5 ++
arch/arm64/crypto/Makefile | 3 +
arch/arm64/crypto/nh-neon-core.S | 103 +++++++++++++++++++++++
arch/arm64/crypto/nhpoly1305-neon-glue.c | 77 +++++++++++++++++
4 files changed, 188 insertions(+)
create mode 100644 arch/arm64/crypto/nh-neon-core.S
create mode 100644 arch/arm64/crypto/nhpoly1305-neon-glue.c
diff --git a/arch/arm64/crypto/Kconfig b/arch/arm64/crypto/Kconfig
index a5606823ed4da..3f5aeb786192b 100644
--- a/arch/arm64/crypto/Kconfig
+++ b/arch/arm64/crypto/Kconfig
@@ -106,6 +106,11 @@ config CRYPTO_CHACHA20_NEON
select CRYPTO_BLKCIPHER
select CRYPTO_CHACHA20
+config CRYPTO_NHPOLY1305_NEON
+ tristate "NHPoly1305 hash function using NEON instructions (for Adiantum)"
+ depends on KERNEL_MODE_NEON
+ select CRYPTO_NHPOLY1305
+
config CRYPTO_AES_ARM64_BS
tristate "AES in ECB/CBC/CTR/XTS modes using bit-sliced NEON algorithm"
depends on KERNEL_MODE_NEON
diff --git a/arch/arm64/crypto/Makefile b/arch/arm64/crypto/Makefile
index f476fede09ba4..125dbb10a93ed 100644
--- a/arch/arm64/crypto/Makefile
+++ b/arch/arm64/crypto/Makefile
@@ -53,6 +53,9 @@ sha512-arm64-y := sha512-glue.o sha512-core.o
obj-$(CONFIG_CRYPTO_CHACHA20_NEON) += chacha20-neon.o
chacha20-neon-y := chacha20-neon-core.o chacha20-neon-glue.o
+obj-$(CONFIG_CRYPTO_NHPOLY1305_NEON) += nhpoly1305-neon.o
+nhpoly1305-neon-y := nh-neon-core.o nhpoly1305-neon-glue.o
+
obj-$(CONFIG_CRYPTO_AES_ARM64) += aes-arm64.o
aes-arm64-y := aes-cipher-core.o aes-cipher-glue.o
diff --git a/arch/arm64/crypto/nh-neon-core.S b/arch/arm64/crypto/nh-neon-core.S
new file mode 100644
index 0000000000000..e08d57676127a
--- /dev/null
+++ b/arch/arm64/crypto/nh-neon-core.S
@@ -0,0 +1,103 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * NH - ε-almost-universal hash function, ARM64 NEON accelerated version
+ *
+ * Copyright 2018 Google LLC
+ *
+ * Author: Eric Biggers <ebiggers@xxxxxxxxxx>
+ */
+
+#include <linux/linkage.h>
+
+ KEY .req x0
+ MESSAGE .req x1
+ MESSAGE_LEN .req x2
+ HASH .req x3
+
+ PASS0_SUMS .req v0
+ PASS1_SUMS .req v1
+ PASS2_SUMS .req v2
+ PASS3_SUMS .req v3
+ K0 .req v4
+ K1 .req v5
+ K2 .req v6
+ K3 .req v7
+ T0 .req v8
+ T1 .req v9
+ T2 .req v10
+ T3 .req v11
+ T4 .req v12
+ T5 .req v13
+ T6 .req v14
+ T7 .req v15
+
+.macro _nh_stride k0, k1, k2, k3
+
+ // Load next message stride
+ ld1 {T3.16b}, [MESSAGE], #16
+
+ // Load next key stride
+ ld1 {\k3\().4s}, [KEY], #16
+
+ // Add message words to key words
+ add T0.4s, T3.4s, \k0\().4s
+ add T1.4s, T3.4s, \k1\().4s
+ add T2.4s, T3.4s, \k2\().4s
+ add T3.4s, T3.4s, \k3\().4s
+
+ // Multiply 32x32 => 64 and accumulate
+ mov T4.d[0], T0.d[1]
+ mov T5.d[0], T1.d[1]
+ mov T6.d[0], T2.d[1]
+ mov T7.d[0], T3.d[1]
+ umlal PASS0_SUMS.2d, T0.2s, T4.2s
+ umlal PASS1_SUMS.2d, T1.2s, T5.2s
+ umlal PASS2_SUMS.2d, T2.2s, T6.2s
+ umlal PASS3_SUMS.2d, T3.2s, T7.2s
+.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)
+
+ ld1 {K0.4s,K1.4s}, [KEY], #32
+ movi PASS0_SUMS.2d, #0
+ movi PASS1_SUMS.2d, #0
+ ld1 {K2.4s}, [KEY], #16
+ movi PASS2_SUMS.2d, #0
+ movi PASS3_SUMS.2d, #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'
+ addp T0.2d, PASS0_SUMS.2d, PASS1_SUMS.2d
+ addp T1.2d, PASS2_SUMS.2d, PASS3_SUMS.2d
+ st1 {T0.16b,T1.16b}, [HASH]
+ ret
+ENDPROC(nh_neon)
diff --git a/arch/arm64/crypto/nhpoly1305-neon-glue.c b/arch/arm64/crypto/nhpoly1305-neon-glue.c
new file mode 100644
index 0000000000000..22cc32ac9448d
--- /dev/null
+++ b/arch/arm64/crypto/nhpoly1305-neon-glue.c
@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * NHPoly1305 - ε-almost-∆-universal hash function for Adiantum
+ * (ARM64 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]);
+
+/* wrapper to avoid indirect call to assembly, which doesn't work with CFI */
+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 = {
+ .base.cra_name = "nhpoly1305",
+ .base.cra_driver_name = "nhpoly1305-neon",
+ .base.cra_priority = 200,
+ .base.cra_ctxsize = sizeof(struct nhpoly1305_key),
+ .base.cra_module = THIS_MODULE,
+ .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),
+};
+
+static int __init nhpoly1305_mod_init(void)
+{
+ if (!(elf_hwcap & HWCAP_ASIMD))
+ 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@xxxxxxxxxx>");
+MODULE_ALIAS_CRYPTO("nhpoly1305");
+MODULE_ALIAS_CRYPTO("nhpoly1305-neon");
--
2.19.2
