diff options
author | Eric Biggers <ebiggers@google.com> | 2018-11-17 04:26:25 +0300 |
---|---|---|
committer | Herbert Xu <herbert@gondor.apana.org.au> | 2018-11-20 09:26:56 +0300 |
commit | 3cc215198eac75cc4130729ddd94a5cdbdb4d300 (patch) | |
tree | 1c1f1c2e8e355f421154ca364853665891fa89a8 | |
parent | d97a94309d764ed907d4281da6246f5d935166f8 (diff) | |
download | linux-3cc215198eac75cc4130729ddd94a5cdbdb4d300.tar.xz |
crypto: arm/chacha20 - refactor to allow varying number of rounds
In preparation for adding XChaCha12 support, rename/refactor the NEON
implementation of ChaCha20 to support different numbers of rounds.
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
-rw-r--r-- | arch/arm/crypto/Makefile | 4 | ||||
-rw-r--r-- | arch/arm/crypto/chacha-neon-core.S (renamed from arch/arm/crypto/chacha20-neon-core.S) | 44 | ||||
-rw-r--r-- | arch/arm/crypto/chacha-neon-glue.c (renamed from arch/arm/crypto/chacha20-neon-glue.c) | 56 |
3 files changed, 56 insertions, 48 deletions
diff --git a/arch/arm/crypto/Makefile b/arch/arm/crypto/Makefile index bd5bceef0605..005482ff9504 100644 --- a/arch/arm/crypto/Makefile +++ b/arch/arm/crypto/Makefile @@ -9,7 +9,7 @@ obj-$(CONFIG_CRYPTO_SHA1_ARM) += sha1-arm.o obj-$(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-$(CONFIG_CRYPTO_CHACHA20_NEON) += chacha20-neon.o +obj-$(CONFIG_CRYPTO_CHACHA20_NEON) += chacha-neon.o ce-obj-$(CONFIG_CRYPTO_AES_ARM_CE) += aes-arm-ce.o ce-obj-$(CONFIG_CRYPTO_SHA1_ARM_CE) += sha1-arm-ce.o @@ -52,7 +52,7 @@ aes-arm-ce-y := aes-ce-core.o aes-ce-glue.o 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 -chacha20-neon-y := chacha20-neon-core.o chacha20-neon-glue.o +chacha-neon-y := chacha-neon-core.o chacha-neon-glue.o ifdef REGENERATE_ARM_CRYPTO quiet_cmd_perl = PERL $@ diff --git a/arch/arm/crypto/chacha20-neon-core.S b/arch/arm/crypto/chacha-neon-core.S index 2335e5055d2b..eb22926d4912 100644 --- a/arch/arm/crypto/chacha20-neon-core.S +++ b/arch/arm/crypto/chacha-neon-core.S @@ -1,5 +1,5 @@ /* - * ChaCha20 256-bit cipher algorithm, RFC7539, ARM NEON functions + * ChaCha/XChaCha NEON helper functions * * Copyright (C) 2016 Linaro, Ltd. <ard.biesheuvel@linaro.org> * @@ -27,9 +27,9 @@ * (d) vtbl.8 + vtbl.8 (multiple of 8 bits rotations only, * needs index vector) * - * ChaCha20 has 16, 12, 8, and 7-bit rotations. For the 12 and 7-bit - * rotations, the only choices are (a) and (b). We use (a) since it takes - * two-thirds the cycles of (b) on both Cortex-A7 and Cortex-A53. + * ChaCha has 16, 12, 8, and 7-bit rotations. For the 12 and 7-bit rotations, + * the only choices are (a) and (b). We use (a) since it takes two-thirds the + * cycles of (b) on both Cortex-A7 and Cortex-A53. * * For the 16-bit rotation, we use vrev32.16 since it's consistently fastest * and doesn't need a temporary register. @@ -53,18 +53,19 @@ .align 5 /* - * chacha20_permute - permute one block + * chacha_permute - permute one block * * Permute one 64-byte block where the state matrix is stored in the four NEON * registers q0-q3. It performs matrix operations on four words in parallel, * but requires shuffling to rearrange the words after each round. * + * The round count is given in r3. + * * Clobbers: r3, ip, q4-q5 */ -chacha20_permute: +chacha_permute: adr ip, .Lrol8_table - mov r3, #10 vld1.8 {d10}, [ip, :64] .Ldoubleround: @@ -128,16 +129,17 @@ chacha20_permute: // x3 = shuffle32(x3, MASK(0, 3, 2, 1)) vext.8 q3, q3, q3, #4 - subs r3, r3, #1 + subs r3, r3, #2 bne .Ldoubleround bx lr -ENDPROC(chacha20_permute) +ENDPROC(chacha_permute) -ENTRY(chacha20_block_xor_neon) +ENTRY(chacha_block_xor_neon) // r0: Input state matrix, s // r1: 1 data block output, o // r2: 1 data block input, i + // r3: nrounds push {lr} // x0..3 = s0..3 @@ -150,7 +152,7 @@ ENTRY(chacha20_block_xor_neon) vmov q10, q2 vmov q11, q3 - bl chacha20_permute + bl chacha_permute add ip, r2, #0x20 vld1.8 {q4-q5}, [r2] @@ -177,30 +179,32 @@ ENTRY(chacha20_block_xor_neon) vst1.8 {q2-q3}, [ip] pop {pc} -ENDPROC(chacha20_block_xor_neon) +ENDPROC(chacha_block_xor_neon) -ENTRY(hchacha20_block_neon) +ENTRY(hchacha_block_neon) // r0: Input state matrix, s // r1: output (8 32-bit words) + // r2: nrounds push {lr} vld1.32 {q0-q1}, [r0]! vld1.32 {q2-q3}, [r0] - bl chacha20_permute + mov r3, r2 + bl chacha_permute vst1.32 {q0}, [r1]! vst1.32 {q3}, [r1] pop {pc} -ENDPROC(hchacha20_block_neon) +ENDPROC(hchacha_block_neon) .align 4 .Lctrinc: .word 0, 1, 2, 3 .Lrol8_table: .byte 3, 0, 1, 2, 7, 4, 5, 6 .align 5 -ENTRY(chacha20_4block_xor_neon) +ENTRY(chacha_4block_xor_neon) push {r4-r5} mov r4, sp // preserve the stack pointer sub ip, sp, #0x20 // allocate a 32 byte buffer @@ -210,9 +214,10 @@ ENTRY(chacha20_4block_xor_neon) // r0: Input state matrix, s // r1: 4 data blocks output, o // r2: 4 data blocks input, i + // r3: nrounds // - // This function encrypts four consecutive ChaCha20 blocks by loading + // This function encrypts four consecutive ChaCha 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. The words are re-interleaved before the @@ -245,7 +250,6 @@ ENTRY(chacha20_4block_xor_neon) vdup.32 q0, d0[0] adr ip, .Lrol8_table - mov r3, #10 b 1f .Ldoubleround4: @@ -443,7 +447,7 @@ ENTRY(chacha20_4block_xor_neon) vsri.u32 q5, q8, #25 vsri.u32 q6, q9, #25 - subs r3, r3, #1 + subs r3, r3, #2 bne .Ldoubleround4 // x0..7[0-3] are in q0-q7, x10..15[0-3] are in q10-q15. @@ -553,4 +557,4 @@ ENTRY(chacha20_4block_xor_neon) pop {r4-r5} bx lr -ENDPROC(chacha20_4block_xor_neon) +ENDPROC(chacha_4block_xor_neon) diff --git a/arch/arm/crypto/chacha20-neon-glue.c b/arch/arm/crypto/chacha-neon-glue.c index f2d3b0f70a8d..385557d38634 100644 --- a/arch/arm/crypto/chacha20-neon-glue.c +++ b/arch/arm/crypto/chacha-neon-glue.c @@ -28,24 +28,26 @@ #include <asm/neon.h> #include <asm/simd.h> -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); -asmlinkage void hchacha20_block_neon(const u32 *state, u32 *out); - -static void chacha20_doneon(u32 *state, u8 *dst, const u8 *src, - unsigned int bytes) +asmlinkage void chacha_block_xor_neon(const u32 *state, u8 *dst, const u8 *src, + int nrounds); +asmlinkage void chacha_4block_xor_neon(const u32 *state, u8 *dst, const u8 *src, + int nrounds); +asmlinkage void hchacha_block_neon(const u32 *state, u32 *out, int nrounds); + +static void chacha_doneon(u32 *state, u8 *dst, const u8 *src, + unsigned int bytes, int nrounds) { u8 buf[CHACHA_BLOCK_SIZE]; while (bytes >= CHACHA_BLOCK_SIZE * 4) { - chacha20_4block_xor_neon(state, dst, src); + chacha_4block_xor_neon(state, dst, src, nrounds); bytes -= CHACHA_BLOCK_SIZE * 4; src += CHACHA_BLOCK_SIZE * 4; dst += CHACHA_BLOCK_SIZE * 4; state[12] += 4; } while (bytes >= CHACHA_BLOCK_SIZE) { - chacha20_block_xor_neon(state, dst, src); + chacha_block_xor_neon(state, dst, src, nrounds); bytes -= CHACHA_BLOCK_SIZE; src += CHACHA_BLOCK_SIZE; dst += CHACHA_BLOCK_SIZE; @@ -53,13 +55,13 @@ static void chacha20_doneon(u32 *state, u8 *dst, const u8 *src, } if (bytes) { memcpy(buf, src, bytes); - chacha20_block_xor_neon(state, buf, buf); + chacha_block_xor_neon(state, buf, buf, nrounds); memcpy(dst, buf, bytes); } } -static int chacha20_neon_stream_xor(struct skcipher_request *req, - struct chacha_ctx *ctx, u8 *iv) +static int chacha_neon_stream_xor(struct skcipher_request *req, + struct chacha_ctx *ctx, u8 *iv) { struct skcipher_walk walk; u32 state[16]; @@ -76,8 +78,8 @@ static int chacha20_neon_stream_xor(struct skcipher_request *req, nbytes = round_down(nbytes, walk.stride); kernel_neon_begin(); - chacha20_doneon(state, walk.dst.virt.addr, walk.src.virt.addr, - nbytes); + chacha_doneon(state, walk.dst.virt.addr, walk.src.virt.addr, + nbytes, ctx->nrounds); kernel_neon_end(); err = skcipher_walk_done(&walk, walk.nbytes - nbytes); } @@ -85,7 +87,7 @@ static int chacha20_neon_stream_xor(struct skcipher_request *req, return err; } -static int chacha20_neon(struct skcipher_request *req) +static int chacha_neon(struct skcipher_request *req) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm); @@ -93,10 +95,10 @@ static int chacha20_neon(struct skcipher_request *req) if (req->cryptlen <= CHACHA_BLOCK_SIZE || !may_use_simd()) return crypto_chacha_crypt(req); - return chacha20_neon_stream_xor(req, ctx, req->iv); + return chacha_neon_stream_xor(req, ctx, req->iv); } -static int xchacha20_neon(struct skcipher_request *req) +static int xchacha_neon(struct skcipher_request *req) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm); @@ -110,12 +112,13 @@ static int xchacha20_neon(struct skcipher_request *req) crypto_chacha_init(state, ctx, req->iv); kernel_neon_begin(); - hchacha20_block_neon(state, subctx.key); + hchacha_block_neon(state, subctx.key, ctx->nrounds); kernel_neon_end(); + subctx.nrounds = ctx->nrounds; memcpy(&real_iv[0], req->iv + 24, 8); memcpy(&real_iv[8], req->iv + 16, 8); - return chacha20_neon_stream_xor(req, &subctx, real_iv); + return chacha_neon_stream_xor(req, &subctx, real_iv); } static struct skcipher_alg algs[] = { @@ -133,8 +136,8 @@ static struct skcipher_alg algs[] = { .chunksize = CHACHA_BLOCK_SIZE, .walksize = 4 * CHACHA_BLOCK_SIZE, .setkey = crypto_chacha20_setkey, - .encrypt = chacha20_neon, - .decrypt = chacha20_neon, + .encrypt = chacha_neon, + .decrypt = chacha_neon, }, { .base.cra_name = "xchacha20", .base.cra_driver_name = "xchacha20-neon", @@ -149,12 +152,12 @@ static struct skcipher_alg algs[] = { .chunksize = CHACHA_BLOCK_SIZE, .walksize = 4 * CHACHA_BLOCK_SIZE, .setkey = crypto_chacha20_setkey, - .encrypt = xchacha20_neon, - .decrypt = xchacha20_neon, + .encrypt = xchacha_neon, + .decrypt = xchacha_neon, } }; -static int __init chacha20_simd_mod_init(void) +static int __init chacha_simd_mod_init(void) { if (!(elf_hwcap & HWCAP_NEON)) return -ENODEV; @@ -162,14 +165,15 @@ static int __init chacha20_simd_mod_init(void) return crypto_register_skciphers(algs, ARRAY_SIZE(algs)); } -static void __exit chacha20_simd_mod_fini(void) +static void __exit chacha_simd_mod_fini(void) { crypto_unregister_skciphers(algs, ARRAY_SIZE(algs)); } -module_init(chacha20_simd_mod_init); -module_exit(chacha20_simd_mod_fini); +module_init(chacha_simd_mod_init); +module_exit(chacha_simd_mod_fini); +MODULE_DESCRIPTION("ChaCha and XChaCha stream ciphers (NEON accelerated)"); MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>"); MODULE_LICENSE("GPL v2"); MODULE_ALIAS_CRYPTO("chacha20"); |