From b7171ce9eb523fd90e38f2d138d1b6ed2ff3eafd Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 11 Jan 2017 16:41:49 +0000 Subject: [PATCH] crypto: arm64/chacha20 - implement NEON version based on SSE3 code This is a straight port to arm64/NEON of the x86 SSE3 implementation of the ChaCha20 stream cipher. It uses the new skcipher walksize attribute to process the input in strides of 4x the block size. Signed-off-by: Ard Biesheuvel Signed-off-by: Herbert Xu --- arch/arm64/crypto/Kconfig | 6 + arch/arm64/crypto/Makefile | 3 + arch/arm64/crypto/chacha20-neon-core.S | 450 +++++++++++++++++++++++++ arch/arm64/crypto/chacha20-neon-glue.c | 127 +++++++ 4 files changed, 586 insertions(+) create mode 100644 arch/arm64/crypto/chacha20-neon-core.S create mode 100644 arch/arm64/crypto/chacha20-neon-glue.c diff --git a/arch/arm64/crypto/Kconfig b/arch/arm64/crypto/Kconfig index 450a85df041a..0bf0f531f539 100644 --- a/arch/arm64/crypto/Kconfig +++ b/arch/arm64/crypto/Kconfig @@ -72,4 +72,10 @@ config CRYPTO_CRC32_ARM64 depends on ARM64 select CRYPTO_HASH +config CRYPTO_CHACHA20_NEON + tristate "NEON accelerated ChaCha20 symmetric cipher" + depends on KERNEL_MODE_NEON + select CRYPTO_BLKCIPHER + select CRYPTO_CHACHA20 + endif diff --git a/arch/arm64/crypto/Makefile b/arch/arm64/crypto/Makefile index aa8888d7b744..9d2826c5fccf 100644 --- a/arch/arm64/crypto/Makefile +++ b/arch/arm64/crypto/Makefile @@ -41,6 +41,9 @@ sha256-arm64-y := sha256-glue.o sha256-core.o obj-$(CONFIG_CRYPTO_SHA512_ARM64) += sha512-arm64.o sha512-arm64-y := sha512-glue.o sha512-core.o +obj-$(CONFIG_CRYPTO_CHACHA20_NEON) += chacha20-neon.o +chacha20-neon-y := chacha20-neon-core.o chacha20-neon-glue.o + AFLAGS_aes-ce.o := -DINTERLEAVE=4 AFLAGS_aes-neon.o := -DINTERLEAVE=4 diff --git a/arch/arm64/crypto/chacha20-neon-core.S b/arch/arm64/crypto/chacha20-neon-core.S new file mode 100644 index 000000000000..13c85e272c2a --- /dev/null +++ b/arch/arm64/crypto/chacha20-neon-core.S @@ -0,0 +1,450 @@ +/* + * ChaCha20 256-bit cipher algorithm, RFC7539, arm64 NEON functions + * + * Copyright (C) 2016 Linaro, Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Based on: + * 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 + + .text + .align 6 + +ENTRY(chacha20_block_xor_neon) + // x0: Input state matrix, s + // x1: 1 data block output, o + // x2: 1 data block input, i + + // + // This function encrypts one ChaCha20 block by loading the state matrix + // in four NEON registers. It performs matrix operation on four words in + // parallel, but requires shuffling to rearrange the words after each + // round. + // + + // x0..3 = s0..3 + adr x3, ROT8 + ld1 {v0.4s-v3.4s}, [x0] + ld1 {v8.4s-v11.4s}, [x0] + ld1 {v12.4s}, [x3] + + mov x3, #10 + +.Ldoubleround: + // x0 += x1, x3 = rotl32(x3 ^ x0, 16) + add v0.4s, v0.4s, v1.4s + eor v3.16b, v3.16b, v0.16b + rev32 v3.8h, v3.8h + + // x2 += x3, x1 = rotl32(x1 ^ x2, 12) + add v2.4s, v2.4s, v3.4s + eor v4.16b, v1.16b, v2.16b + shl v1.4s, v4.4s, #12 + sri v1.4s, v4.4s, #20 + + // x0 += x1, x3 = rotl32(x3 ^ x0, 8) + add v0.4s, v0.4s, v1.4s + eor v3.16b, v3.16b, v0.16b + tbl v3.16b, {v3.16b}, v12.16b + + // x2 += x3, x1 = rotl32(x1 ^ x2, 7) + add v2.4s, v2.4s, v3.4s + eor v4.16b, v1.16b, v2.16b + shl v1.4s, v4.4s, #7 + sri v1.4s, v4.4s, #25 + + // x1 = shuffle32(x1, MASK(0, 3, 2, 1)) + ext v1.16b, v1.16b, v1.16b, #4 + // x2 = shuffle32(x2, MASK(1, 0, 3, 2)) + ext v2.16b, v2.16b, v2.16b, #8 + // x3 = shuffle32(x3, MASK(2, 1, 0, 3)) + ext v3.16b, v3.16b, v3.16b, #12 + + // x0 += x1, x3 = rotl32(x3 ^ x0, 16) + add v0.4s, v0.4s, v1.4s + eor v3.16b, v3.16b, v0.16b + rev32 v3.8h, v3.8h + + // x2 += x3, x1 = rotl32(x1 ^ x2, 12) + add v2.4s, v2.4s, v3.4s + eor v4.16b, v1.16b, v2.16b + shl v1.4s, v4.4s, #12 + sri v1.4s, v4.4s, #20 + + // x0 += x1, x3 = rotl32(x3 ^ x0, 8) + add v0.4s, v0.4s, v1.4s + eor v3.16b, v3.16b, v0.16b + tbl v3.16b, {v3.16b}, v12.16b + + // x2 += x3, x1 = rotl32(x1 ^ x2, 7) + add v2.4s, v2.4s, v3.4s + eor v4.16b, v1.16b, v2.16b + shl v1.4s, v4.4s, #7 + sri v1.4s, v4.4s, #25 + + // x1 = shuffle32(x1, MASK(2, 1, 0, 3)) + ext v1.16b, v1.16b, v1.16b, #12 + // x2 = shuffle32(x2, MASK(1, 0, 3, 2)) + ext v2.16b, v2.16b, v2.16b, #8 + // x3 = shuffle32(x3, MASK(0, 3, 2, 1)) + ext v3.16b, v3.16b, v3.16b, #4 + + subs x3, x3, #1 + b.ne .Ldoubleround + + ld1 {v4.16b-v7.16b}, [x2] + + // o0 = i0 ^ (x0 + s0) + add v0.4s, v0.4s, v8.4s + eor v0.16b, v0.16b, v4.16b + + // o1 = i1 ^ (x1 + s1) + add v1.4s, v1.4s, v9.4s + eor v1.16b, v1.16b, v5.16b + + // o2 = i2 ^ (x2 + s2) + add v2.4s, v2.4s, v10.4s + eor v2.16b, v2.16b, v6.16b + + // o3 = i3 ^ (x3 + s3) + add v3.4s, v3.4s, v11.4s + eor v3.16b, v3.16b, v7.16b + + st1 {v0.16b-v3.16b}, [x1] + + ret +ENDPROC(chacha20_block_xor_neon) + + .align 6 +ENTRY(chacha20_4block_xor_neon) + // x0: Input state matrix, s + // x1: 4 data blocks output, o + // x2: 4 data blocks input, i + + // + // This function encrypts four consecutive ChaCha20 blocks by loading + // the state matrix in NEON registers four times. The algorithm performs + // each operation on the corresponding word of each state matrix, hence + // requires no word shuffling. For final XORing step we transpose the + // matrix by interleaving 32- and then 64-bit words, which allows us to + // do XOR in NEON registers. + // + adr x3, CTRINC // ... and ROT8 + ld1 {v30.4s-v31.4s}, [x3] + + // x0..15[0-3] = s0..3[0..3] + mov x4, x0 + ld4r { v0.4s- v3.4s}, [x4], #16 + ld4r { v4.4s- v7.4s}, [x4], #16 + ld4r { v8.4s-v11.4s}, [x4], #16 + ld4r {v12.4s-v15.4s}, [x4] + + // x12 += counter values 0-3 + add v12.4s, v12.4s, v30.4s + + mov x3, #10 + +.Ldoubleround4: + // x0 += x4, x12 = rotl32(x12 ^ x0, 16) + // x1 += x5, x13 = rotl32(x13 ^ x1, 16) + // x2 += x6, x14 = rotl32(x14 ^ x2, 16) + // x3 += x7, x15 = rotl32(x15 ^ x3, 16) + add v0.4s, v0.4s, v4.4s + add v1.4s, v1.4s, v5.4s + add v2.4s, v2.4s, v6.4s + add v3.4s, v3.4s, v7.4s + + eor v12.16b, v12.16b, v0.16b + eor v13.16b, v13.16b, v1.16b + eor v14.16b, v14.16b, v2.16b + eor v15.16b, v15.16b, v3.16b + + rev32 v12.8h, v12.8h + rev32 v13.8h, v13.8h + rev32 v14.8h, v14.8h + rev32 v15.8h, v15.8h + + // x8 += x12, x4 = rotl32(x4 ^ x8, 12) + // x9 += x13, x5 = rotl32(x5 ^ x9, 12) + // x10 += x14, x6 = rotl32(x6 ^ x10, 12) + // x11 += x15, x7 = rotl32(x7 ^ x11, 12) + add v8.4s, v8.4s, v12.4s + add v9.4s, v9.4s, v13.4s + add v10.4s, v10.4s, v14.4s + add v11.4s, v11.4s, v15.4s + + eor v16.16b, v4.16b, v8.16b + eor v17.16b, v5.16b, v9.16b + eor v18.16b, v6.16b, v10.16b + eor v19.16b, v7.16b, v11.16b + + shl v4.4s, v16.4s, #12 + shl v5.4s, v17.4s, #12 + shl v6.4s, v18.4s, #12 + shl v7.4s, v19.4s, #12 + + sri v4.4s, v16.4s, #20 + sri v5.4s, v17.4s, #20 + sri v6.4s, v18.4s, #20 + sri v7.4s, v19.4s, #20 + + // x0 += x4, x12 = rotl32(x12 ^ x0, 8) + // x1 += x5, x13 = rotl32(x13 ^ x1, 8) + // x2 += x6, x14 = rotl32(x14 ^ x2, 8) + // x3 += x7, x15 = rotl32(x15 ^ x3, 8) + add v0.4s, v0.4s, v4.4s + add v1.4s, v1.4s, v5.4s + add v2.4s, v2.4s, v6.4s + add v3.4s, v3.4s, v7.4s + + eor v12.16b, v12.16b, v0.16b + eor v13.16b, v13.16b, v1.16b + eor v14.16b, v14.16b, v2.16b + eor v15.16b, v15.16b, v3.16b + + tbl v12.16b, {v12.16b}, v31.16b + tbl v13.16b, {v13.16b}, v31.16b + tbl v14.16b, {v14.16b}, v31.16b + tbl v15.16b, {v15.16b}, v31.16b + + // x8 += x12, x4 = rotl32(x4 ^ x8, 7) + // x9 += x13, x5 = rotl32(x5 ^ x9, 7) + // x10 += x14, x6 = rotl32(x6 ^ x10, 7) + // x11 += x15, x7 = rotl32(x7 ^ x11, 7) + add v8.4s, v8.4s, v12.4s + add v9.4s, v9.4s, v13.4s + add v10.4s, v10.4s, v14.4s + add v11.4s, v11.4s, v15.4s + + eor v16.16b, v4.16b, v8.16b + eor v17.16b, v5.16b, v9.16b + eor v18.16b, v6.16b, v10.16b + eor v19.16b, v7.16b, v11.16b + + shl v4.4s, v16.4s, #7 + shl v5.4s, v17.4s, #7 + shl v6.4s, v18.4s, #7 + shl v7.4s, v19.4s, #7 + + sri v4.4s, v16.4s, #25 + sri v5.4s, v17.4s, #25 + sri v6.4s, v18.4s, #25 + sri v7.4s, v19.4s, #25 + + // x0 += x5, x15 = rotl32(x15 ^ x0, 16) + // x1 += x6, x12 = rotl32(x12 ^ x1, 16) + // x2 += x7, x13 = rotl32(x13 ^ x2, 16) + // x3 += x4, x14 = rotl32(x14 ^ x3, 16) + add v0.4s, v0.4s, v5.4s + add v1.4s, v1.4s, v6.4s + add v2.4s, v2.4s, v7.4s + add v3.4s, v3.4s, v4.4s + + eor v15.16b, v15.16b, v0.16b + eor v12.16b, v12.16b, v1.16b + eor v13.16b, v13.16b, v2.16b + eor v14.16b, v14.16b, v3.16b + + rev32 v15.8h, v15.8h + rev32 v12.8h, v12.8h + rev32 v13.8h, v13.8h + rev32 v14.8h, v14.8h + + // x10 += x15, x5 = rotl32(x5 ^ x10, 12) + // x11 += x12, x6 = rotl32(x6 ^ x11, 12) + // x8 += x13, x7 = rotl32(x7 ^ x8, 12) + // x9 += x14, x4 = rotl32(x4 ^ x9, 12) + add v10.4s, v10.4s, v15.4s + add v11.4s, v11.4s, v12.4s + add v8.4s, v8.4s, v13.4s + add v9.4s, v9.4s, v14.4s + + eor v16.16b, v5.16b, v10.16b + eor v17.16b, v6.16b, v11.16b + eor v18.16b, v7.16b, v8.16b + eor v19.16b, v4.16b, v9.16b + + shl v5.4s, v16.4s, #12 + shl v6.4s, v17.4s, #12 + shl v7.4s, v18.4s, #12 + shl v4.4s, v19.4s, #12 + + sri v5.4s, v16.4s, #20 + sri v6.4s, v17.4s, #20 + sri v7.4s, v18.4s, #20 + sri v4.4s, v19.4s, #20 + + // x0 += x5, x15 = rotl32(x15 ^ x0, 8) + // x1 += x6, x12 = rotl32(x12 ^ x1, 8) + // x2 += x7, x13 = rotl32(x13 ^ x2, 8) + // x3 += x4, x14 = rotl32(x14 ^ x3, 8) + add v0.4s, v0.4s, v5.4s + add v1.4s, v1.4s, v6.4s + add v2.4s, v2.4s, v7.4s + add v3.4s, v3.4s, v4.4s + + eor v15.16b, v15.16b, v0.16b + eor v12.16b, v12.16b, v1.16b + eor v13.16b, v13.16b, v2.16b + eor v14.16b, v14.16b, v3.16b + + tbl v15.16b, {v15.16b}, v31.16b + tbl v12.16b, {v12.16b}, v31.16b + tbl v13.16b, {v13.16b}, v31.16b + tbl v14.16b, {v14.16b}, v31.16b + + // x10 += x15, x5 = rotl32(x5 ^ x10, 7) + // x11 += x12, x6 = rotl32(x6 ^ x11, 7) + // x8 += x13, x7 = rotl32(x7 ^ x8, 7) + // x9 += x14, x4 = rotl32(x4 ^ x9, 7) + add v10.4s, v10.4s, v15.4s + add v11.4s, v11.4s, v12.4s + add v8.4s, v8.4s, v13.4s + add v9.4s, v9.4s, v14.4s + + eor v16.16b, v5.16b, v10.16b + eor v17.16b, v6.16b, v11.16b + eor v18.16b, v7.16b, v8.16b + eor v19.16b, v4.16b, v9.16b + + shl v5.4s, v16.4s, #7 + shl v6.4s, v17.4s, #7 + shl v7.4s, v18.4s, #7 + shl v4.4s, v19.4s, #7 + + sri v5.4s, v16.4s, #25 + sri v6.4s, v17.4s, #25 + sri v7.4s, v18.4s, #25 + sri v4.4s, v19.4s, #25 + + subs x3, x3, #1 + b.ne .Ldoubleround4 + + ld4r {v16.4s-v19.4s}, [x0], #16 + ld4r {v20.4s-v23.4s}, [x0], #16 + + // x12 += counter values 0-3 + add v12.4s, v12.4s, v30.4s + + // x0[0-3] += s0[0] + // x1[0-3] += s0[1] + // x2[0-3] += s0[2] + // x3[0-3] += s0[3] + add v0.4s, v0.4s, v16.4s + add v1.4s, v1.4s, v17.4s + add v2.4s, v2.4s, v18.4s + add v3.4s, v3.4s, v19.4s + + ld4r {v24.4s-v27.4s}, [x0], #16 + ld4r {v28.4s-v31.4s}, [x0] + + // x4[0-3] += s1[0] + // x5[0-3] += s1[1] + // x6[0-3] += s1[2] + // x7[0-3] += s1[3] + add v4.4s, v4.4s, v20.4s + add v5.4s, v5.4s, v21.4s + add v6.4s, v6.4s, v22.4s + add v7.4s, v7.4s, v23.4s + + // x8[0-3] += s2[0] + // x9[0-3] += s2[1] + // x10[0-3] += s2[2] + // x11[0-3] += s2[3] + add v8.4s, v8.4s, v24.4s + add v9.4s, v9.4s, v25.4s + add v10.4s, v10.4s, v26.4s + add v11.4s, v11.4s, v27.4s + + // x12[0-3] += s3[0] + // x13[0-3] += s3[1] + // x14[0-3] += s3[2] + // x15[0-3] += s3[3] + add v12.4s, v12.4s, v28.4s + add v13.4s, v13.4s, v29.4s + add v14.4s, v14.4s, v30.4s + add v15.4s, v15.4s, v31.4s + + // interleave 32-bit words in state n, n+1 + zip1 v16.4s, v0.4s, v1.4s + zip2 v17.4s, v0.4s, v1.4s + zip1 v18.4s, v2.4s, v3.4s + zip2 v19.4s, v2.4s, v3.4s + zip1 v20.4s, v4.4s, v5.4s + zip2 v21.4s, v4.4s, v5.4s + zip1 v22.4s, v6.4s, v7.4s + zip2 v23.4s, v6.4s, v7.4s + zip1 v24.4s, v8.4s, v9.4s + zip2 v25.4s, v8.4s, v9.4s + zip1 v26.4s, v10.4s, v11.4s + zip2 v27.4s, v10.4s, v11.4s + zip1 v28.4s, v12.4s, v13.4s + zip2 v29.4s, v12.4s, v13.4s + zip1 v30.4s, v14.4s, v15.4s + zip2 v31.4s, v14.4s, v15.4s + + // interleave 64-bit words in state n, n+2 + zip1 v0.2d, v16.2d, v18.2d + zip2 v4.2d, v16.2d, v18.2d + zip1 v8.2d, v17.2d, v19.2d + zip2 v12.2d, v17.2d, v19.2d + ld1 {v16.16b-v19.16b}, [x2], #64 + + zip1 v1.2d, v20.2d, v22.2d + zip2 v5.2d, v20.2d, v22.2d + zip1 v9.2d, v21.2d, v23.2d + zip2 v13.2d, v21.2d, v23.2d + ld1 {v20.16b-v23.16b}, [x2], #64 + + zip1 v2.2d, v24.2d, v26.2d + zip2 v6.2d, v24.2d, v26.2d + zip1 v10.2d, v25.2d, v27.2d + zip2 v14.2d, v25.2d, v27.2d + ld1 {v24.16b-v27.16b}, [x2], #64 + + zip1 v3.2d, v28.2d, v30.2d + zip2 v7.2d, v28.2d, v30.2d + zip1 v11.2d, v29.2d, v31.2d + zip2 v15.2d, v29.2d, v31.2d + ld1 {v28.16b-v31.16b}, [x2] + + // xor with corresponding input, write to output + eor v16.16b, v16.16b, v0.16b + eor v17.16b, v17.16b, v1.16b + eor v18.16b, v18.16b, v2.16b + eor v19.16b, v19.16b, v3.16b + eor v20.16b, v20.16b, v4.16b + eor v21.16b, v21.16b, v5.16b + st1 {v16.16b-v19.16b}, [x1], #64 + eor v22.16b, v22.16b, v6.16b + eor v23.16b, v23.16b, v7.16b + eor v24.16b, v24.16b, v8.16b + eor v25.16b, v25.16b, v9.16b + st1 {v20.16b-v23.16b}, [x1], #64 + eor v26.16b, v26.16b, v10.16b + eor v27.16b, v27.16b, v11.16b + eor v28.16b, v28.16b, v12.16b + st1 {v24.16b-v27.16b}, [x1], #64 + eor v29.16b, v29.16b, v13.16b + eor v30.16b, v30.16b, v14.16b + eor v31.16b, v31.16b, v15.16b + st1 {v28.16b-v31.16b}, [x1] + + ret +ENDPROC(chacha20_4block_xor_neon) + +CTRINC: .word 0, 1, 2, 3 +ROT8: .word 0x02010003, 0x06050407, 0x0a09080b, 0x0e0d0c0f diff --git a/arch/arm64/crypto/chacha20-neon-glue.c b/arch/arm64/crypto/chacha20-neon-glue.c new file mode 100644 index 000000000000..a7f2337d46cf --- /dev/null +++ b/arch/arm64/crypto/chacha20-neon-glue.c @@ -0,0 +1,127 @@ +/* + * ChaCha20 256-bit cipher algorithm, RFC7539, arm64 NEON functions + * + * Copyright (C) 2016 Linaro, Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Based on: + * 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 +#include +#include +#include +#include + +#include +#include + +asmlinkage void chacha20_block_xor_neon(u32 *state, u8 *dst, const u8 *src); +asmlinkage void chacha20_4block_xor_neon(u32 *state, u8 *dst, const u8 *src); + +static void chacha20_doneon(u32 *state, u8 *dst, const u8 *src, + unsigned int bytes) +{ + u8 buf[CHACHA20_BLOCK_SIZE]; + + while (bytes >= CHACHA20_BLOCK_SIZE * 4) { + chacha20_4block_xor_neon(state, dst, src); + bytes -= CHACHA20_BLOCK_SIZE * 4; + src += CHACHA20_BLOCK_SIZE * 4; + dst += CHACHA20_BLOCK_SIZE * 4; + state[12] += 4; + } + while (bytes >= CHACHA20_BLOCK_SIZE) { + chacha20_block_xor_neon(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_neon(state, buf, buf); + memcpy(dst, buf, bytes); + } +} + +static int chacha20_neon(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct chacha20_ctx *ctx = crypto_skcipher_ctx(tfm); + struct skcipher_walk walk; + u32 state[16]; + int err; + + if (req->cryptlen <= CHACHA20_BLOCK_SIZE) + return crypto_chacha20_crypt(req); + + err = skcipher_walk_virt(&walk, req, true); + + crypto_chacha20_init(state, ctx, walk.iv); + + kernel_neon_begin(); + while (walk.nbytes > 0) { + unsigned int nbytes = walk.nbytes; + + if (nbytes < walk.total) + nbytes = round_down(nbytes, walk.stride); + + chacha20_doneon(state, walk.dst.virt.addr, walk.src.virt.addr, + nbytes); + err = skcipher_walk_done(&walk, walk.nbytes - nbytes); + } + kernel_neon_end(); + + return err; +} + +static struct skcipher_alg alg = { + .base.cra_name = "chacha20", + .base.cra_driver_name = "chacha20-neon", + .base.cra_priority = 300, + .base.cra_blocksize = 1, + .base.cra_ctxsize = sizeof(struct chacha20_ctx), + .base.cra_alignmask = 1, + .base.cra_module = THIS_MODULE, + + .min_keysize = CHACHA20_KEY_SIZE, + .max_keysize = CHACHA20_KEY_SIZE, + .ivsize = CHACHA20_IV_SIZE, + .chunksize = CHACHA20_BLOCK_SIZE, + .walksize = 4 * CHACHA20_BLOCK_SIZE, + .setkey = crypto_chacha20_setkey, + .encrypt = chacha20_neon, + .decrypt = chacha20_neon, +}; + +static int __init chacha20_simd_mod_init(void) +{ + if (!(elf_hwcap & HWCAP_ASIMD)) + return -ENODEV; + + return crypto_register_skcipher(&alg); +} + +static void __exit chacha20_simd_mod_fini(void) +{ + crypto_unregister_skcipher(&alg); +} + +module_init(chacha20_simd_mod_init); +module_exit(chacha20_simd_mod_fini); + +MODULE_AUTHOR("Ard Biesheuvel "); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS_CRYPTO("chacha20");