From 281c7a2341978ef7d20d72d1aa882bb846ac83ab Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Fri, 8 Nov 2019 13:22:10 +0100 Subject: [PATCH] crypto: x86/chacha - expose SIMD ChaCha routine as library function Wire the existing x86 SIMD ChaCha code into the new ChaCha library interface, so that users of the library interface will get the accelerated version when available. Given that calls into the library API will always go through the routines in this module if it is enabled, switch to static keys to select the optimal implementation available (which may be none at all, in which case we defer to the generic implementation for all invocations). Signed-off-by: Ard Biesheuvel Signed-off-by: Herbert Xu --- arch/x86/crypto/chacha_glue.c | 91 +++++++++++++++++++++++++---------- crypto/Kconfig | 1 + include/crypto/chacha.h | 6 +++ 3 files changed, 73 insertions(+), 25 deletions(-) diff --git a/arch/x86/crypto/chacha_glue.c b/arch/x86/crypto/chacha_glue.c index 0aabb382edce0..b391e13a9e415 100644 --- a/arch/x86/crypto/chacha_glue.c +++ b/arch/x86/crypto/chacha_glue.c @@ -21,24 +21,24 @@ asmlinkage void chacha_block_xor_ssse3(u32 *state, u8 *dst, const u8 *src, asmlinkage void chacha_4block_xor_ssse3(u32 *state, u8 *dst, const u8 *src, unsigned int len, int nrounds); asmlinkage void hchacha_block_ssse3(const u32 *state, u32 *out, int nrounds); -#ifdef CONFIG_AS_AVX2 + asmlinkage void chacha_2block_xor_avx2(u32 *state, u8 *dst, const u8 *src, unsigned int len, int nrounds); asmlinkage void chacha_4block_xor_avx2(u32 *state, u8 *dst, const u8 *src, unsigned int len, int nrounds); asmlinkage void chacha_8block_xor_avx2(u32 *state, u8 *dst, const u8 *src, unsigned int len, int nrounds); -static bool chacha_use_avx2; -#ifdef CONFIG_AS_AVX512 + asmlinkage void chacha_2block_xor_avx512vl(u32 *state, u8 *dst, const u8 *src, unsigned int len, int nrounds); asmlinkage void chacha_4block_xor_avx512vl(u32 *state, u8 *dst, const u8 *src, unsigned int len, int nrounds); asmlinkage void chacha_8block_xor_avx512vl(u32 *state, u8 *dst, const u8 *src, unsigned int len, int nrounds); -static bool chacha_use_avx512vl; -#endif -#endif + +static __ro_after_init DEFINE_STATIC_KEY_FALSE(chacha_use_simd); +static __ro_after_init DEFINE_STATIC_KEY_FALSE(chacha_use_avx2); +static __ro_after_init DEFINE_STATIC_KEY_FALSE(chacha_use_avx512vl); static unsigned int chacha_advance(unsigned int len, unsigned int maxblocks) { @@ -49,9 +49,8 @@ static unsigned int chacha_advance(unsigned int len, unsigned int maxblocks) static void chacha_dosimd(u32 *state, u8 *dst, const u8 *src, unsigned int bytes, int nrounds) { -#ifdef CONFIG_AS_AVX2 -#ifdef CONFIG_AS_AVX512 - if (chacha_use_avx512vl) { + if (IS_ENABLED(CONFIG_AS_AVX512) && + static_branch_likely(&chacha_use_avx512vl)) { while (bytes >= CHACHA_BLOCK_SIZE * 8) { chacha_8block_xor_avx512vl(state, dst, src, bytes, nrounds); @@ -79,8 +78,9 @@ static void chacha_dosimd(u32 *state, u8 *dst, const u8 *src, return; } } -#endif - if (chacha_use_avx2) { + + if (IS_ENABLED(CONFIG_AS_AVX2) && + static_branch_likely(&chacha_use_avx2)) { while (bytes >= CHACHA_BLOCK_SIZE * 8) { chacha_8block_xor_avx2(state, dst, src, bytes, nrounds); bytes -= CHACHA_BLOCK_SIZE * 8; @@ -104,7 +104,7 @@ static void chacha_dosimd(u32 *state, u8 *dst, const u8 *src, return; } } -#endif + while (bytes >= CHACHA_BLOCK_SIZE * 4) { chacha_4block_xor_ssse3(state, dst, src, bytes, nrounds); bytes -= CHACHA_BLOCK_SIZE * 4; @@ -123,6 +123,43 @@ static void chacha_dosimd(u32 *state, u8 *dst, const u8 *src, } } +void hchacha_block_arch(const u32 *state, u32 *stream, int nrounds) +{ + state = PTR_ALIGN(state, CHACHA_STATE_ALIGN); + + if (!static_branch_likely(&chacha_use_simd) || !crypto_simd_usable()) { + hchacha_block_generic(state, stream, nrounds); + } else { + kernel_fpu_begin(); + hchacha_block_ssse3(state, stream, nrounds); + kernel_fpu_end(); + } +} +EXPORT_SYMBOL(hchacha_block_arch); + +void chacha_init_arch(u32 *state, const u32 *key, const u8 *iv) +{ + state = PTR_ALIGN(state, CHACHA_STATE_ALIGN); + + chacha_init_generic(state, key, iv); +} +EXPORT_SYMBOL(chacha_init_arch); + +void chacha_crypt_arch(u32 *state, u8 *dst, const u8 *src, unsigned int bytes, + int nrounds) +{ + state = PTR_ALIGN(state, CHACHA_STATE_ALIGN); + + if (!static_branch_likely(&chacha_use_simd) || !crypto_simd_usable() || + bytes <= CHACHA_BLOCK_SIZE) + return chacha_crypt_generic(state, dst, src, bytes, nrounds); + + kernel_fpu_begin(); + chacha_dosimd(state, dst, src, bytes, nrounds); + kernel_fpu_end(); +} +EXPORT_SYMBOL(chacha_crypt_arch); + static int chacha_simd_stream_xor(struct skcipher_request *req, const struct chacha_ctx *ctx, const u8 *iv) { @@ -143,7 +180,8 @@ static int chacha_simd_stream_xor(struct skcipher_request *req, if (nbytes < walk.total) nbytes = round_down(nbytes, walk.stride); - if (!crypto_simd_usable()) { + if (!static_branch_likely(&chacha_use_simd) || + !crypto_simd_usable()) { chacha_crypt_generic(state, walk.dst.virt.addr, walk.src.virt.addr, nbytes, ctx->nrounds); @@ -246,18 +284,21 @@ static struct skcipher_alg algs[] = { static int __init chacha_simd_mod_init(void) { if (!boot_cpu_has(X86_FEATURE_SSSE3)) - return -ENODEV; - -#ifdef CONFIG_AS_AVX2 - chacha_use_avx2 = boot_cpu_has(X86_FEATURE_AVX) && - boot_cpu_has(X86_FEATURE_AVX2) && - cpu_has_xfeatures(XFEATURE_MASK_SSE | XFEATURE_MASK_YMM, NULL); -#ifdef CONFIG_AS_AVX512 - chacha_use_avx512vl = chacha_use_avx2 && - boot_cpu_has(X86_FEATURE_AVX512VL) && - boot_cpu_has(X86_FEATURE_AVX512BW); /* kmovq */ -#endif -#endif + return 0; + + static_branch_enable(&chacha_use_simd); + + if (IS_ENABLED(CONFIG_AS_AVX2) && + boot_cpu_has(X86_FEATURE_AVX) && + boot_cpu_has(X86_FEATURE_AVX2) && + cpu_has_xfeatures(XFEATURE_MASK_SSE | XFEATURE_MASK_YMM, NULL)) { + static_branch_enable(&chacha_use_avx2); + + if (IS_ENABLED(CONFIG_AS_AVX512) && + boot_cpu_has(X86_FEATURE_AVX512VL) && + boot_cpu_has(X86_FEATURE_AVX512BW)) /* kmovq */ + static_branch_enable(&chacha_use_avx512vl); + } return crypto_register_skciphers(algs, ARRAY_SIZE(algs)); } diff --git a/crypto/Kconfig b/crypto/Kconfig index 1abca30ed6aef..07762de1237fc 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -1437,6 +1437,7 @@ config CRYPTO_CHACHA20_X86_64 depends on X86 && 64BIT select CRYPTO_SKCIPHER select CRYPTO_LIB_CHACHA_GENERIC + select CRYPTO_ARCH_HAVE_LIB_CHACHA help SSSE3, AVX2, and AVX-512VL optimized implementations of the ChaCha20, XChaCha20, and XChaCha12 stream ciphers. diff --git a/include/crypto/chacha.h b/include/crypto/chacha.h index 5c662f8fecac0..2676f4fbd4c16 100644 --- a/include/crypto/chacha.h +++ b/include/crypto/chacha.h @@ -25,6 +25,12 @@ #define CHACHA_BLOCK_SIZE 64 #define CHACHAPOLY_IV_SIZE 12 +#ifdef CONFIG_X86_64 +#define CHACHA_STATE_WORDS ((CHACHA_BLOCK_SIZE + 12) / sizeof(u32)) +#else +#define CHACHA_STATE_WORDS (CHACHA_BLOCK_SIZE / sizeof(u32)) +#endif + /* 192-bit nonce, then 64-bit stream position */ #define XCHACHA_IV_SIZE 32 -- 2.39.5