[RFC PATCH] crypto: arm64/speck - add NEON-accelerated implementation of Speck-XTS
Eric Biggers
ebiggers at google.com
Mon Mar 5 11:17:07 PST 2018
Add a NEON-accelerated implementation of Speck128-XTS and Speck64-XTS
for ARM64. This is ported from the 32-bit version. It may be useful on
devices with 64-bit ARM CPUs that don't have the Cryptography
Extensions, so cannot do AES efficiently -- e.g. the Cortex-A53
processor on the Raspberry Pi 3.
It generally works the same way as the 32-bit version, but there are
some slight differences due to the different instructions, registers,
and syntax available in ARM64 vs. in ARM32. For example, in the 64-bit
version there are enough registers to hold the XTS tweaks for each
128-byte chunk, so they don't need to be saved on the stack.
Benchmarks on a Raspberry Pi 3 running a 64-bit kernel:
Algorithm Encryption Decryption
--------- ---------- ----------
Speck64/128-XTS (NEON) 92.2 MB/s 92.2 MB/s
Speck128/256-XTS (NEON) 75.0 MB/s 75.0 MB/s
Speck128/256-XTS (generic) 47.4 MB/s 35.6 MB/s
AES-128-XTS (NEON bit-sliced) 33.4 MB/s 29.6 MB/s
AES-256-XTS (NEON bit-sliced) 24.6 MB/s 21.7 MB/s
The code performs well on higher-end ARM64 processors as well, though
such processors tend to have the Crypto Extensions which make AES
preferred. For example, here are the same benchmarks run on a HiKey960
(with CPU affinity set for the A73 cores), with the Crypto Extensions
implementation of AES-256-XTS added:
Algorithm Encryption Decryption
--------- ----------- -----------
AES-256-XTS (Crypto Extensions) 1273.3 MB/s 1274.7 MB/s
Speck64/128-XTS (NEON) 359.8 MB/s 348.0 MB/s
Speck128/256-XTS (NEON) 292.5 MB/s 286.1 MB/s
Speck128/256-XTS (generic) 186.3 MB/s 181.8 MB/s
AES-128-XTS (NEON bit-sliced) 142.0 MB/s 124.3 MB/s
AES-256-XTS (NEON bit-sliced) 104.7 MB/s 91.1 MB/s
Signed-off-by: Eric Biggers <ebiggers at google.com>
---
arch/arm64/crypto/Kconfig | 6 +
arch/arm64/crypto/Makefile | 3 +
arch/arm64/crypto/speck-neon-core.S | 352 ++++++++++++++++++++++++++++
arch/arm64/crypto/speck-neon-glue.c | 282 ++++++++++++++++++++++
4 files changed, 643 insertions(+)
create mode 100644 arch/arm64/crypto/speck-neon-core.S
create mode 100644 arch/arm64/crypto/speck-neon-glue.c
diff --git a/arch/arm64/crypto/Kconfig b/arch/arm64/crypto/Kconfig
index 285c36c7b408..cb5a243110c4 100644
--- a/arch/arm64/crypto/Kconfig
+++ b/arch/arm64/crypto/Kconfig
@@ -113,4 +113,10 @@ config CRYPTO_AES_ARM64_BS
select CRYPTO_AES_ARM64
select CRYPTO_SIMD
+config CRYPTO_SPECK_NEON
+ tristate "NEON accelerated Speck cipher algorithms"
+ depends on KERNEL_MODE_NEON
+ select CRYPTO_BLKCIPHER
+ select CRYPTO_SPECK
+
endif
diff --git a/arch/arm64/crypto/Makefile b/arch/arm64/crypto/Makefile
index cee9b8d9830b..d94ebd15a859 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_SPECK_NEON) += speck-neon.o
+speck-neon-y := speck-neon-core.o speck-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/speck-neon-core.S b/arch/arm64/crypto/speck-neon-core.S
new file mode 100644
index 000000000000..b14463438b09
--- /dev/null
+++ b/arch/arm64/crypto/speck-neon-core.S
@@ -0,0 +1,352 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM64 NEON-accelerated implementation of Speck128-XTS and Speck64-XTS
+ *
+ * Copyright (c) 2018 Google, Inc
+ *
+ * Author: Eric Biggers <ebiggers at google.com>
+ */
+
+#include <linux/linkage.h>
+
+ .text
+
+ // arguments
+ ROUND_KEYS .req x0 // const {u64,u32} *round_keys
+ NROUNDS .req w1 // int nrounds
+ NROUNDS_X .req x1
+ DST .req x2 // void *dst
+ SRC .req x3 // const void *src
+ NBYTES .req w4 // unsigned int nbytes
+ TWEAK .req x5 // void *tweak
+
+ // registers which hold the data being encrypted/decrypted
+ // (underscores avoid a naming collision with ARM64 registers x0-x3)
+ X_0 .req v0
+ Y_0 .req v1
+ X_1 .req v2
+ Y_1 .req v3
+ X_2 .req v4
+ Y_2 .req v5
+ X_3 .req v6
+ Y_3 .req v7
+
+ // the round key, duplicated in all lanes
+ ROUND_KEY .req v8
+
+ // index vector for tbl-based 8-bit rotates
+ ROTATE_TABLE .req v9
+ ROTATE_TABLE_Q .req q9
+
+ // temporary registers
+ TMP0 .req v10
+ TMP1 .req v11
+ TMP2 .req v12
+ TMP3 .req v13
+
+ // multiplication table for updating XTS tweaks
+ GFMUL_TABLE .req v14
+ GFMUL_TABLE_Q .req q14
+
+ // next XTS tweak value(s)
+ TWEAKV_NEXT .req v15
+
+ // XTS tweaks for the blocks currently being encrypted/decrypted
+ TWEAKV0 .req v16
+ TWEAKV1 .req v17
+ TWEAKV2 .req v18
+ TWEAKV3 .req v19
+ TWEAKV4 .req v20
+ TWEAKV5 .req v21
+ TWEAKV6 .req v22
+ TWEAKV7 .req v23
+
+ .align 4
+.Lror64_8_table:
+ .octa 0x080f0e0d0c0b0a090007060504030201
+.Lror32_8_table:
+ .octa 0x0c0f0e0d080b0a090407060500030201
+.Lrol64_8_table:
+ .octa 0x0e0d0c0b0a09080f0605040302010007
+.Lrol32_8_table:
+ .octa 0x0e0d0c0f0a09080b0605040702010003
+.Lgf128mul_table:
+ .octa 0x00000000000000870000000000000001
+.Lgf64mul_table:
+ .octa 0x0000000000000000000000002d361b00
+
+/*
+ * _speck_round_128bytes() - Speck encryption round on 128 bytes at a time
+ *
+ * Do one Speck encryption round on the 128 bytes (8 blocks for Speck128, 16 for
+ * Speck64) stored in X0-X3 and Y0-Y3, using the round key stored in all lanes
+ * of ROUND_KEY. 'n' is the lane size: 64 for Speck128, or 32 for Speck64.
+ * 'lanes' is the lane specifier: "2d" for Speck128 or "4s" for Speck64.
+ */
+.macro _speck_round_128bytes n, lanes
+
+ // x = ror(x, 8)
+ tbl X_0.16b, {X_0.16b}, ROTATE_TABLE.16b
+ tbl X_1.16b, {X_1.16b}, ROTATE_TABLE.16b
+ tbl X_2.16b, {X_2.16b}, ROTATE_TABLE.16b
+ tbl X_3.16b, {X_3.16b}, ROTATE_TABLE.16b
+
+ // x += y
+ add X_0.\lanes, X_0.\lanes, Y_0.\lanes
+ add X_1.\lanes, X_1.\lanes, Y_1.\lanes
+ add X_2.\lanes, X_2.\lanes, Y_2.\lanes
+ add X_3.\lanes, X_3.\lanes, Y_3.\lanes
+
+ // x ^= k
+ eor X_0.16b, X_0.16b, ROUND_KEY.16b
+ eor X_1.16b, X_1.16b, ROUND_KEY.16b
+ eor X_2.16b, X_2.16b, ROUND_KEY.16b
+ eor X_3.16b, X_3.16b, ROUND_KEY.16b
+
+ // y = rol(y, 3)
+ shl TMP0.\lanes, Y_0.\lanes, #3
+ shl TMP1.\lanes, Y_1.\lanes, #3
+ shl TMP2.\lanes, Y_2.\lanes, #3
+ shl TMP3.\lanes, Y_3.\lanes, #3
+ sri TMP0.\lanes, Y_0.\lanes, #(\n - 3)
+ sri TMP1.\lanes, Y_1.\lanes, #(\n - 3)
+ sri TMP2.\lanes, Y_2.\lanes, #(\n - 3)
+ sri TMP3.\lanes, Y_3.\lanes, #(\n - 3)
+
+ // y ^= x
+ eor Y_0.16b, TMP0.16b, X_0.16b
+ eor Y_1.16b, TMP1.16b, X_1.16b
+ eor Y_2.16b, TMP2.16b, X_2.16b
+ eor Y_3.16b, TMP3.16b, X_3.16b
+.endm
+
+/*
+ * _speck_unround_128bytes() - Speck decryption round on 128 bytes at a time
+ *
+ * This is the inverse of _speck_round_128bytes().
+ */
+.macro _speck_unround_128bytes n, lanes
+
+ // y ^= x
+ eor TMP0.16b, Y_0.16b, X_0.16b
+ eor TMP1.16b, Y_1.16b, X_1.16b
+ eor TMP2.16b, Y_2.16b, X_2.16b
+ eor TMP3.16b, Y_3.16b, X_3.16b
+
+ // y = ror(y, 3)
+ ushr Y_0.\lanes, TMP0.\lanes, #3
+ ushr Y_1.\lanes, TMP1.\lanes, #3
+ ushr Y_2.\lanes, TMP2.\lanes, #3
+ ushr Y_3.\lanes, TMP3.\lanes, #3
+ sli Y_0.\lanes, TMP0.\lanes, #(\n - 3)
+ sli Y_1.\lanes, TMP1.\lanes, #(\n - 3)
+ sli Y_2.\lanes, TMP2.\lanes, #(\n - 3)
+ sli Y_3.\lanes, TMP3.\lanes, #(\n - 3)
+
+ // x ^= k
+ eor X_0.16b, X_0.16b, ROUND_KEY.16b
+ eor X_1.16b, X_1.16b, ROUND_KEY.16b
+ eor X_2.16b, X_2.16b, ROUND_KEY.16b
+ eor X_3.16b, X_3.16b, ROUND_KEY.16b
+
+ // x -= y
+ sub X_0.\lanes, X_0.\lanes, Y_0.\lanes
+ sub X_1.\lanes, X_1.\lanes, Y_1.\lanes
+ sub X_2.\lanes, X_2.\lanes, Y_2.\lanes
+ sub X_3.\lanes, X_3.\lanes, Y_3.\lanes
+
+ // x = rol(x, 8)
+ tbl X_0.16b, {X_0.16b}, ROTATE_TABLE.16b
+ tbl X_1.16b, {X_1.16b}, ROTATE_TABLE.16b
+ tbl X_2.16b, {X_2.16b}, ROTATE_TABLE.16b
+ tbl X_3.16b, {X_3.16b}, ROTATE_TABLE.16b
+.endm
+
+.macro _next_xts_tweak next, cur, tmp, n
+.if \n == 64
+ /*
+ * Calculate the next tweak by multiplying the current one by x,
+ * modulo p(x) = x^128 + x^7 + x^2 + x + 1.
+ */
+ sshr \tmp\().2d, \cur\().2d, #63
+ and \tmp\().16b, \tmp\().16b, GFMUL_TABLE.16b
+ shl \next\().2d, \cur\().2d, #1
+ ext \tmp\().16b, \tmp\().16b, \tmp\().16b, #8
+ eor \next\().16b, \next\().16b, \tmp\().16b
+.else
+ /*
+ * Calculate the next two tweaks by multiplying the current ones by x^2,
+ * modulo p(x) = x^64 + x^4 + x^3 + x + 1.
+ */
+ ushr \tmp\().2d, \cur\().2d, #62
+ shl \next\().2d, \cur\().2d, #2
+ tbl \tmp\().16b, {GFMUL_TABLE.16b}, \tmp\().16b
+ eor \next\().16b, \next\().16b, \tmp\().16b
+.endif
+.endm
+
+/*
+ * _speck_xts_crypt() - Speck-XTS encryption/decryption
+ *
+ * Encrypt or decrypt NBYTES bytes of data from the SRC buffer to the DST buffer
+ * using Speck-XTS, specifically the variant with a block size of '2n' and round
+ * count given by NROUNDS. The expanded round keys are given in ROUND_KEYS, and
+ * the current XTS tweak value is given in TWEAK. It's assumed that NBYTES is a
+ * nonzero multiple of 128.
+ */
+.macro _speck_xts_crypt n, lanes, decrypting
+
+ /*
+ * If decrypting, modify the ROUND_KEYS parameter to point to the last
+ * round key rather than the first, since for decryption the round keys
+ * are used in reverse order.
+ */
+.if \decrypting
+ mov NROUNDS, NROUNDS /* zero the high 32 bits */
+.if \n == 64
+ add ROUND_KEYS, ROUND_KEYS, NROUNDS_X, lsl #3
+ sub ROUND_KEYS, ROUND_KEYS, #8
+.else
+ add ROUND_KEYS, ROUND_KEYS, NROUNDS_X, lsl #2
+ sub ROUND_KEYS, ROUND_KEYS, #4
+.endif
+.endif
+
+ // Load the index vector for tbl-based 8-bit rotates
+.if \decrypting
+ ldr ROTATE_TABLE_Q, .Lrol\n\()_8_table
+.else
+ ldr ROTATE_TABLE_Q, .Lror\n\()_8_table
+.endif
+
+ // One-time XTS preparation
+.if \n == 64
+ // Load first tweak
+ ld1 {TWEAKV0.16b}, [TWEAK]
+
+ // Load GF(2^128) multiplication table
+ ldr GFMUL_TABLE_Q, .Lgf128mul_table
+.else
+ // Load first tweak
+ ld1 {TWEAKV0.8b}, [TWEAK]
+
+ // Load GF(2^64) multiplication table
+ ldr GFMUL_TABLE_Q, .Lgf64mul_table
+
+ // Calculate second tweak, packing it together with the first
+ ushr TMP0.2d, TWEAKV0.2d, #63
+ shl TMP1.2d, TWEAKV0.2d, #1
+ tbl TMP0.8b, {GFMUL_TABLE.16b}, TMP0.8b
+ eor TMP0.8b, TMP0.8b, TMP1.8b
+ mov TWEAKV0.d[1], TMP0.d[0]
+.endif
+
+.Lnext_128bytes_\@:
+
+ // Calculate XTS tweaks for next 128 bytes
+ _next_xts_tweak TWEAKV1, TWEAKV0, TMP0, \n
+ _next_xts_tweak TWEAKV2, TWEAKV1, TMP0, \n
+ _next_xts_tweak TWEAKV3, TWEAKV2, TMP0, \n
+ _next_xts_tweak TWEAKV4, TWEAKV3, TMP0, \n
+ _next_xts_tweak TWEAKV5, TWEAKV4, TMP0, \n
+ _next_xts_tweak TWEAKV6, TWEAKV5, TMP0, \n
+ _next_xts_tweak TWEAKV7, TWEAKV6, TMP0, \n
+ _next_xts_tweak TWEAKV_NEXT, TWEAKV7, TMP0, \n
+
+ // Load the next source blocks into {X,Y}[0-3]
+ ld1 {X_0.16b-Y_1.16b}, [SRC], #64
+ ld1 {X_2.16b-Y_3.16b}, [SRC], #64
+
+ // XOR the source blocks with their XTS tweaks
+ eor TMP0.16b, X_0.16b, TWEAKV0.16b
+ eor Y_0.16b, Y_0.16b, TWEAKV1.16b
+ eor TMP1.16b, X_1.16b, TWEAKV2.16b
+ eor Y_1.16b, Y_1.16b, TWEAKV3.16b
+ eor TMP2.16b, X_2.16b, TWEAKV4.16b
+ eor Y_2.16b, Y_2.16b, TWEAKV5.16b
+ eor TMP3.16b, X_3.16b, TWEAKV6.16b
+ eor Y_3.16b, Y_3.16b, TWEAKV7.16b
+
+ /*
+ * De-interleave the 'x' and 'y' elements of each block, i.e. make it so
+ * that the X[0-3] registers contain only the second halves of blocks,
+ * and the Y[0-3] registers contain only the first halves of blocks.
+ * (Speck uses the order (y, x) rather than the more intuitive (x, y).)
+ */
+ uzp2 X_0.\lanes, TMP0.\lanes, Y_0.\lanes
+ uzp1 Y_0.\lanes, TMP0.\lanes, Y_0.\lanes
+ uzp2 X_1.\lanes, TMP1.\lanes, Y_1.\lanes
+ uzp1 Y_1.\lanes, TMP1.\lanes, Y_1.\lanes
+ uzp2 X_2.\lanes, TMP2.\lanes, Y_2.\lanes
+ uzp1 Y_2.\lanes, TMP2.\lanes, Y_2.\lanes
+ uzp2 X_3.\lanes, TMP3.\lanes, Y_3.\lanes
+ uzp1 Y_3.\lanes, TMP3.\lanes, Y_3.\lanes
+
+ // Do the cipher rounds
+ mov x6, ROUND_KEYS
+ mov w7, NROUNDS
+.Lnext_round_\@:
+.if \decrypting
+ ld1r {ROUND_KEY.\lanes}, [x6]
+ sub x6, x6, #( \n / 8 )
+ _speck_unround_128bytes \n, \lanes
+.else
+ ld1r {ROUND_KEY.\lanes}, [x6], #( \n / 8 )
+ _speck_round_128bytes \n, \lanes
+.endif
+ subs w7, w7, #1
+ bne .Lnext_round_\@
+
+ // Re-interleave the 'x' and 'y' elements of each block
+ zip1 TMP0.\lanes, Y_0.\lanes, X_0.\lanes
+ zip2 Y_0.\lanes, Y_0.\lanes, X_0.\lanes
+ zip1 TMP1.\lanes, Y_1.\lanes, X_1.\lanes
+ zip2 Y_1.\lanes, Y_1.\lanes, X_1.\lanes
+ zip1 TMP2.\lanes, Y_2.\lanes, X_2.\lanes
+ zip2 Y_2.\lanes, Y_2.\lanes, X_2.\lanes
+ zip1 TMP3.\lanes, Y_3.\lanes, X_3.\lanes
+ zip2 Y_3.\lanes, Y_3.\lanes, X_3.\lanes
+
+ // XOR the encrypted/decrypted blocks with the tweaks calculated earlier
+ eor X_0.16b, TMP0.16b, TWEAKV0.16b
+ eor Y_0.16b, Y_0.16b, TWEAKV1.16b
+ eor X_1.16b, TMP1.16b, TWEAKV2.16b
+ eor Y_1.16b, Y_1.16b, TWEAKV3.16b
+ eor X_2.16b, TMP2.16b, TWEAKV4.16b
+ eor Y_2.16b, Y_2.16b, TWEAKV5.16b
+ eor X_3.16b, TMP3.16b, TWEAKV6.16b
+ eor Y_3.16b, Y_3.16b, TWEAKV7.16b
+ mov TWEAKV0.16b, TWEAKV_NEXT.16b
+
+ // Store the ciphertext in the destination buffer
+ st1 {X_0.16b-Y_1.16b}, [DST], #64
+ st1 {X_2.16b-Y_3.16b}, [DST], #64
+
+ // Continue if there are more 128-byte chunks remaining
+ subs NBYTES, NBYTES, #128
+ bne .Lnext_128bytes_\@
+
+ // Store the next tweak and return
+.if \n == 64
+ st1 {TWEAKV_NEXT.16b}, [TWEAK]
+.else
+ st1 {TWEAKV_NEXT.8b}, [TWEAK]
+.endif
+ ret
+.endm
+
+ENTRY(speck128_xts_encrypt_neon)
+ _speck_xts_crypt n=64, lanes=2d, decrypting=0
+ENDPROC(speck128_xts_encrypt_neon)
+
+ENTRY(speck128_xts_decrypt_neon)
+ _speck_xts_crypt n=64, lanes=2d, decrypting=1
+ENDPROC(speck128_xts_decrypt_neon)
+
+ENTRY(speck64_xts_encrypt_neon)
+ _speck_xts_crypt n=32, lanes=4s, decrypting=0
+ENDPROC(speck64_xts_encrypt_neon)
+
+ENTRY(speck64_xts_decrypt_neon)
+ _speck_xts_crypt n=32, lanes=4s, decrypting=1
+ENDPROC(speck64_xts_decrypt_neon)
diff --git a/arch/arm64/crypto/speck-neon-glue.c b/arch/arm64/crypto/speck-neon-glue.c
new file mode 100644
index 000000000000..6e233aeb4ff4
--- /dev/null
+++ b/arch/arm64/crypto/speck-neon-glue.c
@@ -0,0 +1,282 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * NEON-accelerated implementation of Speck128-XTS and Speck64-XTS
+ * (64-bit version; based on the 32-bit version)
+ *
+ * Copyright (c) 2018 Google, Inc
+ */
+
+#include <asm/hwcap.h>
+#include <asm/neon.h>
+#include <asm/simd.h>
+#include <crypto/algapi.h>
+#include <crypto/gf128mul.h>
+#include <crypto/internal/skcipher.h>
+#include <crypto/speck.h>
+#include <crypto/xts.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+/* The assembly functions only handle multiples of 128 bytes */
+#define SPECK_NEON_CHUNK_SIZE 128
+
+/* Speck128 */
+
+struct speck128_xts_tfm_ctx {
+ struct speck128_tfm_ctx main_key;
+ struct speck128_tfm_ctx tweak_key;
+};
+
+asmlinkage void speck128_xts_encrypt_neon(const u64 *round_keys, int nrounds,
+ void *dst, const void *src,
+ unsigned int nbytes, void *tweak);
+
+asmlinkage void speck128_xts_decrypt_neon(const u64 *round_keys, int nrounds,
+ void *dst, const void *src,
+ unsigned int nbytes, void *tweak);
+
+typedef void (*speck128_crypt_one_t)(const struct speck128_tfm_ctx *,
+ u8 *, const u8 *);
+typedef void (*speck128_xts_crypt_many_t)(const u64 *, int, void *,
+ const void *, unsigned int, void *);
+
+static __always_inline int
+__speck128_xts_crypt(struct skcipher_request *req,
+ speck128_crypt_one_t crypt_one,
+ speck128_xts_crypt_many_t crypt_many)
+{
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+ const struct speck128_xts_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);
+ struct skcipher_walk walk;
+ le128 tweak;
+ int err;
+
+ err = skcipher_walk_virt(&walk, req, true);
+
+ crypto_speck128_encrypt(&ctx->tweak_key, (u8 *)&tweak, walk.iv);
+
+ while (walk.nbytes > 0) {
+ unsigned int nbytes = walk.nbytes;
+ u8 *dst = walk.dst.virt.addr;
+ const u8 *src = walk.src.virt.addr;
+
+ if (nbytes >= SPECK_NEON_CHUNK_SIZE && may_use_simd()) {
+ unsigned int count;
+
+ count = round_down(nbytes, SPECK_NEON_CHUNK_SIZE);
+ kernel_neon_begin();
+ (*crypt_many)(ctx->main_key.round_keys,
+ ctx->main_key.nrounds,
+ dst, src, count, &tweak);
+ kernel_neon_end();
+ dst += count;
+ src += count;
+ nbytes -= count;
+ }
+
+ /* Handle any remainder with generic code */
+ while (nbytes >= sizeof(tweak)) {
+ le128_xor((le128 *)dst, (const le128 *)src, &tweak);
+ (*crypt_one)(&ctx->main_key, dst, dst);
+ le128_xor((le128 *)dst, (const le128 *)dst, &tweak);
+ gf128mul_x_ble(&tweak, &tweak);
+
+ dst += sizeof(tweak);
+ src += sizeof(tweak);
+ nbytes -= sizeof(tweak);
+ }
+ err = skcipher_walk_done(&walk, nbytes);
+ }
+
+ return err;
+}
+
+static int speck128_xts_encrypt(struct skcipher_request *req)
+{
+ return __speck128_xts_crypt(req, crypto_speck128_encrypt,
+ speck128_xts_encrypt_neon);
+}
+
+static int speck128_xts_decrypt(struct skcipher_request *req)
+{
+ return __speck128_xts_crypt(req, crypto_speck128_decrypt,
+ speck128_xts_decrypt_neon);
+}
+
+static int speck128_xts_setkey(struct crypto_skcipher *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ struct speck128_xts_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);
+ int err;
+
+ err = xts_verify_key(tfm, key, keylen);
+ if (err)
+ return err;
+
+ keylen /= 2;
+
+ err = crypto_speck128_setkey(&ctx->main_key, key, keylen);
+ if (err)
+ return err;
+
+ return crypto_speck128_setkey(&ctx->tweak_key, key + keylen, keylen);
+}
+
+/* Speck64 */
+
+struct speck64_xts_tfm_ctx {
+ struct speck64_tfm_ctx main_key;
+ struct speck64_tfm_ctx tweak_key;
+};
+
+asmlinkage void speck64_xts_encrypt_neon(const u32 *round_keys, int nrounds,
+ void *dst, const void *src,
+ unsigned int nbytes, void *tweak);
+
+asmlinkage void speck64_xts_decrypt_neon(const u32 *round_keys, int nrounds,
+ void *dst, const void *src,
+ unsigned int nbytes, void *tweak);
+
+typedef void (*speck64_crypt_one_t)(const struct speck64_tfm_ctx *,
+ u8 *, const u8 *);
+typedef void (*speck64_xts_crypt_many_t)(const u32 *, int, void *,
+ const void *, unsigned int, void *);
+
+static __always_inline int
+__speck64_xts_crypt(struct skcipher_request *req, speck64_crypt_one_t crypt_one,
+ speck64_xts_crypt_many_t crypt_many)
+{
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+ const struct speck64_xts_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);
+ struct skcipher_walk walk;
+ __le64 tweak;
+ int err;
+
+ err = skcipher_walk_virt(&walk, req, true);
+
+ crypto_speck64_encrypt(&ctx->tweak_key, (u8 *)&tweak, walk.iv);
+
+ while (walk.nbytes > 0) {
+ unsigned int nbytes = walk.nbytes;
+ u8 *dst = walk.dst.virt.addr;
+ const u8 *src = walk.src.virt.addr;
+
+ if (nbytes >= SPECK_NEON_CHUNK_SIZE && may_use_simd()) {
+ unsigned int count;
+
+ count = round_down(nbytes, SPECK_NEON_CHUNK_SIZE);
+ kernel_neon_begin();
+ (*crypt_many)(ctx->main_key.round_keys,
+ ctx->main_key.nrounds,
+ dst, src, count, &tweak);
+ kernel_neon_end();
+ dst += count;
+ src += count;
+ nbytes -= count;
+ }
+
+ /* Handle any remainder with generic code */
+ while (nbytes >= sizeof(tweak)) {
+ *(__le64 *)dst = *(__le64 *)src ^ tweak;
+ (*crypt_one)(&ctx->main_key, dst, dst);
+ *(__le64 *)dst ^= tweak;
+ tweak = cpu_to_le64((le64_to_cpu(tweak) << 1) ^
+ ((tweak & cpu_to_le64(1ULL << 63)) ?
+ 0x1B : 0));
+ dst += sizeof(tweak);
+ src += sizeof(tweak);
+ nbytes -= sizeof(tweak);
+ }
+ err = skcipher_walk_done(&walk, nbytes);
+ }
+
+ return err;
+}
+
+static int speck64_xts_encrypt(struct skcipher_request *req)
+{
+ return __speck64_xts_crypt(req, crypto_speck64_encrypt,
+ speck64_xts_encrypt_neon);
+}
+
+static int speck64_xts_decrypt(struct skcipher_request *req)
+{
+ return __speck64_xts_crypt(req, crypto_speck64_decrypt,
+ speck64_xts_decrypt_neon);
+}
+
+static int speck64_xts_setkey(struct crypto_skcipher *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ struct speck64_xts_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);
+ int err;
+
+ err = xts_verify_key(tfm, key, keylen);
+ if (err)
+ return err;
+
+ keylen /= 2;
+
+ err = crypto_speck64_setkey(&ctx->main_key, key, keylen);
+ if (err)
+ return err;
+
+ return crypto_speck64_setkey(&ctx->tweak_key, key + keylen, keylen);
+}
+
+static struct skcipher_alg speck_algs[] = {
+ {
+ .base.cra_name = "xts(speck128)",
+ .base.cra_driver_name = "xts-speck128-neon",
+ .base.cra_priority = 300,
+ .base.cra_blocksize = SPECK128_BLOCK_SIZE,
+ .base.cra_ctxsize = sizeof(struct speck128_xts_tfm_ctx),
+ .base.cra_alignmask = 7,
+ .base.cra_module = THIS_MODULE,
+ .min_keysize = 2 * SPECK128_128_KEY_SIZE,
+ .max_keysize = 2 * SPECK128_256_KEY_SIZE,
+ .ivsize = SPECK128_BLOCK_SIZE,
+ .walksize = SPECK_NEON_CHUNK_SIZE,
+ .setkey = speck128_xts_setkey,
+ .encrypt = speck128_xts_encrypt,
+ .decrypt = speck128_xts_decrypt,
+ }, {
+ .base.cra_name = "xts(speck64)",
+ .base.cra_driver_name = "xts-speck64-neon",
+ .base.cra_priority = 300,
+ .base.cra_blocksize = SPECK64_BLOCK_SIZE,
+ .base.cra_ctxsize = sizeof(struct speck64_xts_tfm_ctx),
+ .base.cra_alignmask = 7,
+ .base.cra_module = THIS_MODULE,
+ .min_keysize = 2 * SPECK64_96_KEY_SIZE,
+ .max_keysize = 2 * SPECK64_128_KEY_SIZE,
+ .ivsize = SPECK64_BLOCK_SIZE,
+ .walksize = SPECK_NEON_CHUNK_SIZE,
+ .setkey = speck64_xts_setkey,
+ .encrypt = speck64_xts_encrypt,
+ .decrypt = speck64_xts_decrypt,
+ }
+};
+
+static int __init speck_neon_module_init(void)
+{
+ if (!(elf_hwcap & HWCAP_ASIMD))
+ return -ENODEV;
+ return crypto_register_skciphers(speck_algs, ARRAY_SIZE(speck_algs));
+}
+
+static void __exit speck_neon_module_exit(void)
+{
+ crypto_unregister_skciphers(speck_algs, ARRAY_SIZE(speck_algs));
+}
+
+module_init(speck_neon_module_init);
+module_exit(speck_neon_module_exit);
+
+MODULE_DESCRIPTION("Speck block cipher (NEON-accelerated)");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Eric Biggers <ebiggers at google.com>");
+MODULE_ALIAS_CRYPTO("xts(speck128)");
+MODULE_ALIAS_CRYPTO("xts-speck128-neon");
+MODULE_ALIAS_CRYPTO("xts(speck64)");
+MODULE_ALIAS_CRYPTO("xts-speck64-neon");
--
2.16.2.395.g2e18187dfd-goog
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