arch/x86/crypto/chacha_glue.c - linux/torvalds/linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * x64 SIMD accelerated ChaCha and XChaCha stream ciphers,
  * including ChaCha20 (RFC7539)
  *
  * Copyright (C) 2015 Martin Willi
  */

 #include <crypto/algapi.h>
 #include <crypto/chacha.h>
 #include <crypto/internal/simd.h>
 #include <crypto/internal/skcipher.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <asm/simd.h>

 #define CHACHA_STATE_ALIGN 16

 asmlinkage void chacha_block_xor_ssse3(u32 *state, u8 *dst, const u8 *src,
 				       unsigned int len, int nrounds);
 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 unsigned int chacha_advance(unsigned int len, unsigned int maxblocks)
 {
 	len = min(len, maxblocks * CHACHA_BLOCK_SIZE);
 	return round_up(len, CHACHA_BLOCK_SIZE) / CHACHA_BLOCK_SIZE;
 }

 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) {
 		while (bytes >= CHACHA_BLOCK_SIZE * 8) {
 			chacha_8block_xor_avx512vl(state, dst, src, bytes,
 						   nrounds);
 			bytes -= CHACHA_BLOCK_SIZE * 8;
 			src += CHACHA_BLOCK_SIZE * 8;
 			dst += CHACHA_BLOCK_SIZE * 8;
 			state[12] += 8;
 		}
 		if (bytes > CHACHA_BLOCK_SIZE * 4) {
 			chacha_8block_xor_avx512vl(state, dst, src, bytes,
 						   nrounds);
 			state[12] += chacha_advance(bytes, 8);
 			return;
 		}
 		if (bytes > CHACHA_BLOCK_SIZE * 2) {
 			chacha_4block_xor_avx512vl(state, dst, src, bytes,
 						   nrounds);
 			state[12] += chacha_advance(bytes, 4);
 			return;
 		}
 		if (bytes) {
 			chacha_2block_xor_avx512vl(state, dst, src, bytes,
 						   nrounds);
 			state[12] += chacha_advance(bytes, 2);
 			return;
 		}
 	}
 #endif
 	if (chacha_use_avx2) {
 		while (bytes >= CHACHA_BLOCK_SIZE * 8) {
 			chacha_8block_xor_avx2(state, dst, src, bytes, nrounds);
 			bytes -= CHACHA_BLOCK_SIZE * 8;
 			src += CHACHA_BLOCK_SIZE * 8;
 			dst += CHACHA_BLOCK_SIZE * 8;
 			state[12] += 8;
 		}
 		if (bytes > CHACHA_BLOCK_SIZE * 4) {
 			chacha_8block_xor_avx2(state, dst, src, bytes, nrounds);
 			state[12] += chacha_advance(bytes, 8);
 			return;
 		}
 		if (bytes > CHACHA_BLOCK_SIZE * 2) {
 			chacha_4block_xor_avx2(state, dst, src, bytes, nrounds);
 			state[12] += chacha_advance(bytes, 4);
 			return;
 		}
 		if (bytes > CHACHA_BLOCK_SIZE) {
 			chacha_2block_xor_avx2(state, dst, src, bytes, nrounds);
 			state[12] += chacha_advance(bytes, 2);
 			return;
 		}
 	}
 #endif
 	while (bytes >= CHACHA_BLOCK_SIZE * 4) {
 		chacha_4block_xor_ssse3(state, dst, src, bytes, nrounds);
 		bytes -= CHACHA_BLOCK_SIZE * 4;
 		src += CHACHA_BLOCK_SIZE * 4;
 		dst += CHACHA_BLOCK_SIZE * 4;
 		state[12] += 4;
 	}
 	if (bytes > CHACHA_BLOCK_SIZE) {
 		chacha_4block_xor_ssse3(state, dst, src, bytes, nrounds);
 		state[12] += chacha_advance(bytes, 4);
 		return;
 	}
 	if (bytes) {
 		chacha_block_xor_ssse3(state, dst, src, bytes, nrounds);
 		state[12]++;
 	}
 }

 static int chacha_simd_stream_xor(struct skcipher_walk *walk,
 				  struct chacha_ctx *ctx, u8 *iv)
 {
 	u32 *state, state_buf[16 + 2] __aligned(8);
 	int next_yield = 4096; /* bytes until next FPU yield */
 	int err = 0;

 	BUILD_BUG_ON(CHACHA_STATE_ALIGN != 16);
 	state = PTR_ALIGN(state_buf + 0, CHACHA_STATE_ALIGN);

 	crypto_chacha_init(state, ctx, iv);

 	while (walk->nbytes > 0) {
 		unsigned int nbytes = walk->nbytes;

 		if (nbytes < walk->total) {
 			nbytes = round_down(nbytes, walk->stride);
 			next_yield -= nbytes;
 		}

 		chacha_dosimd(state, walk->dst.virt.addr, walk->src.virt.addr,
 			      nbytes, ctx->nrounds);

 		if (next_yield <= 0) {
 			/* temporarily allow preemption */
 			kernel_fpu_end();
 			kernel_fpu_begin();
 			next_yield = 4096;
 		}

 		err = skcipher_walk_done(walk, walk->nbytes - nbytes);
 	}

 	return err;
 }

 static int chacha_simd(struct skcipher_request *req)
 {
 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 	struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm);
 	struct skcipher_walk walk;
 	int err;

 	if (req->cryptlen <= CHACHA_BLOCK_SIZE || !crypto_simd_usable())
 		return crypto_chacha_crypt(req);

 	err = skcipher_walk_virt(&walk, req, true);
 	if (err)
 		return err;

 	kernel_fpu_begin();
 	err = chacha_simd_stream_xor(&walk, ctx, req->iv);
 	kernel_fpu_end();
 	return err;
 }

 static int xchacha_simd(struct skcipher_request *req)
 {
 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 	struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm);
 	struct skcipher_walk walk;
 	struct chacha_ctx subctx;
 	u32 *state, state_buf[16 + 2] __aligned(8);
 	u8 real_iv[16];
 	int err;

 	if (req->cryptlen <= CHACHA_BLOCK_SIZE || !crypto_simd_usable())
 		return crypto_xchacha_crypt(req);

 	err = skcipher_walk_virt(&walk, req, true);
 	if (err)
 		return err;

 	BUILD_BUG_ON(CHACHA_STATE_ALIGN != 16);
 	state = PTR_ALIGN(state_buf + 0, CHACHA_STATE_ALIGN);
 	crypto_chacha_init(state, ctx, req->iv);

 	kernel_fpu_begin();

 	hchacha_block_ssse3(state, subctx.key, ctx->nrounds);
 	subctx.nrounds = ctx->nrounds;

 	memcpy(&real_iv[0], req->iv + 24, 8);
 	memcpy(&real_iv[8], req->iv + 16, 8);
 	err = chacha_simd_stream_xor(&walk, &subctx, real_iv);

 	kernel_fpu_end();

 	return err;
 }

 static struct skcipher_alg algs[] = {
 	{
 		.base.cra_name		= "chacha20",
 		.base.cra_driver_name	= "chacha20-simd",
 		.base.cra_priority	= 300,
 		.base.cra_blocksize	= 1,
 		.base.cra_ctxsize	= sizeof(struct chacha_ctx),
 		.base.cra_module	= THIS_MODULE,

 		.min_keysize		= CHACHA_KEY_SIZE,
 		.max_keysize		= CHACHA_KEY_SIZE,
 		.ivsize			= CHACHA_IV_SIZE,
 		.chunksize		= CHACHA_BLOCK_SIZE,
 		.setkey			= crypto_chacha20_setkey,
 		.encrypt		= chacha_simd,
 		.decrypt		= chacha_simd,
 	}, {
 		.base.cra_name		= "xchacha20",
 		.base.cra_driver_name	= "xchacha20-simd",
 		.base.cra_priority	= 300,
 		.base.cra_blocksize	= 1,
 		.base.cra_ctxsize	= sizeof(struct chacha_ctx),
 		.base.cra_module	= THIS_MODULE,

 		.min_keysize		= CHACHA_KEY_SIZE,
 		.max_keysize		= CHACHA_KEY_SIZE,
 		.ivsize			= XCHACHA_IV_SIZE,
 		.chunksize		= CHACHA_BLOCK_SIZE,
 		.setkey			= crypto_chacha20_setkey,
 		.encrypt		= xchacha_simd,
 		.decrypt		= xchacha_simd,
 	}, {
 		.base.cra_name		= "xchacha12",
 		.base.cra_driver_name	= "xchacha12-simd",
 		.base.cra_priority	= 300,
 		.base.cra_blocksize	= 1,
 		.base.cra_ctxsize	= sizeof(struct chacha_ctx),
 		.base.cra_module	= THIS_MODULE,

 		.min_keysize		= CHACHA_KEY_SIZE,
 		.max_keysize		= CHACHA_KEY_SIZE,
 		.ivsize			= XCHACHA_IV_SIZE,
 		.chunksize		= CHACHA_BLOCK_SIZE,
 		.setkey			= crypto_chacha12_setkey,
 		.encrypt		= xchacha_simd,
 		.decrypt		= xchacha_simd,
 	},
 };

 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 crypto_register_skciphers(algs, ARRAY_SIZE(algs));
 }

 static void __exit chacha_simd_mod_fini(void)
 {
 	crypto_unregister_skciphers(algs, ARRAY_SIZE(algs));
 }

 module_init(chacha_simd_mod_init);
 module_exit(chacha_simd_mod_fini);

 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Martin Willi <martin@strongswan.org>");
 MODULE_DESCRIPTION("ChaCha and XChaCha stream ciphers (x64 SIMD accelerated)");
 MODULE_ALIAS_CRYPTO("chacha20");
 MODULE_ALIAS_CRYPTO("chacha20-simd");
 MODULE_ALIAS_CRYPTO("xchacha20");
 MODULE_ALIAS_CRYPTO("xchacha20-simd");
 MODULE_ALIAS_CRYPTO("xchacha12");
 MODULE_ALIAS_CRYPTO("xchacha12-simd");
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* x64 SIMD accelerated ChaCha and XChaCha stream ciphers,
	* including ChaCha20 (RFC7539)
	*
	* Copyright (C) 2015 Martin Willi
	*/

	#include <crypto/algapi.h>
	#include <crypto/chacha.h>
	#include <crypto/internal/simd.h>
	#include <crypto/internal/skcipher.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <asm/simd.h>

	#define CHACHA_STATE_ALIGN 16

	asmlinkage void chacha_block_xor_ssse3(u32 state, u8 dst, const u8 *src,
	unsigned int len, int nrounds);
	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 unsigned int chacha_advance(unsigned int len, unsigned int maxblocks)
	{
	len = min(len, maxblocks * CHACHA_BLOCK_SIZE);
	return round_up(len, CHACHA_BLOCK_SIZE) / CHACHA_BLOCK_SIZE;
	}

	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) {
	while (bytes >= CHACHA_BLOCK_SIZE * 8) {
	chacha_8block_xor_avx512vl(state, dst, src, bytes,
	nrounds);
	bytes -= CHACHA_BLOCK_SIZE * 8;
	src += CHACHA_BLOCK_SIZE * 8;
	dst += CHACHA_BLOCK_SIZE * 8;
	state[12] += 8;
	}
	if (bytes > CHACHA_BLOCK_SIZE * 4) {
	chacha_8block_xor_avx512vl(state, dst, src, bytes,
	nrounds);
	state[12] += chacha_advance(bytes, 8);
	return;
	}
	if (bytes > CHACHA_BLOCK_SIZE * 2) {
	chacha_4block_xor_avx512vl(state, dst, src, bytes,
	nrounds);
	state[12] += chacha_advance(bytes, 4);
	return;
	}
	if (bytes) {
	chacha_2block_xor_avx512vl(state, dst, src, bytes,
	nrounds);
	state[12] += chacha_advance(bytes, 2);
	return;
	}
	}
	#endif
	if (chacha_use_avx2) {
	while (bytes >= CHACHA_BLOCK_SIZE * 8) {
	chacha_8block_xor_avx2(state, dst, src, bytes, nrounds);
	bytes -= CHACHA_BLOCK_SIZE * 8;
	src += CHACHA_BLOCK_SIZE * 8;
	dst += CHACHA_BLOCK_SIZE * 8;
	state[12] += 8;
	}
	if (bytes > CHACHA_BLOCK_SIZE * 4) {
	chacha_8block_xor_avx2(state, dst, src, bytes, nrounds);
	state[12] += chacha_advance(bytes, 8);
	return;
	}
	if (bytes > CHACHA_BLOCK_SIZE * 2) {
	chacha_4block_xor_avx2(state, dst, src, bytes, nrounds);
	state[12] += chacha_advance(bytes, 4);
	return;
	}
	if (bytes > CHACHA_BLOCK_SIZE) {
	chacha_2block_xor_avx2(state, dst, src, bytes, nrounds);
	state[12] += chacha_advance(bytes, 2);
	return;
	}
	}
	#endif
	while (bytes >= CHACHA_BLOCK_SIZE * 4) {
	chacha_4block_xor_ssse3(state, dst, src, bytes, nrounds);
	bytes -= CHACHA_BLOCK_SIZE * 4;
	src += CHACHA_BLOCK_SIZE * 4;
	dst += CHACHA_BLOCK_SIZE * 4;
	state[12] += 4;
	}
	if (bytes > CHACHA_BLOCK_SIZE) {
	chacha_4block_xor_ssse3(state, dst, src, bytes, nrounds);
	state[12] += chacha_advance(bytes, 4);
	return;
	}
	if (bytes) {
	chacha_block_xor_ssse3(state, dst, src, bytes, nrounds);
	state[12]++;
	}
	}

	static int chacha_simd_stream_xor(struct skcipher_walk *walk,
	struct chacha_ctx ctx, u8 iv)
	{
	u32 *state, state_buf[16 + 2] __aligned(8);
	int next_yield = 4096; /* bytes until next FPU yield */
	int err = 0;

	BUILD_BUG_ON(CHACHA_STATE_ALIGN != 16);
	state = PTR_ALIGN(state_buf + 0, CHACHA_STATE_ALIGN);

	crypto_chacha_init(state, ctx, iv);

	while (walk->nbytes > 0) {
	unsigned int nbytes = walk->nbytes;

	if (nbytes < walk->total) {
	nbytes = round_down(nbytes, walk->stride);
	next_yield -= nbytes;
	}

	chacha_dosimd(state, walk->dst.virt.addr, walk->src.virt.addr,
	nbytes, ctx->nrounds);

	if (next_yield <= 0) {
	/* temporarily allow preemption */
	kernel_fpu_end();
	kernel_fpu_begin();
	next_yield = 4096;
	}

	err = skcipher_walk_done(walk, walk->nbytes - nbytes);
	}

	return err;
	}

	static int chacha_simd(struct skcipher_request *req)
	{
	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
	struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm);
	struct skcipher_walk walk;
	int err;

	if (req->cryptlen <= CHACHA_BLOCK_SIZE \|\| !crypto_simd_usable())
	return crypto_chacha_crypt(req);

	err = skcipher_walk_virt(&walk, req, true);
	if (err)
	return err;

	kernel_fpu_begin();
	err = chacha_simd_stream_xor(&walk, ctx, req->iv);
	kernel_fpu_end();
	return err;
	}

	static int xchacha_simd(struct skcipher_request *req)
	{
	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
	struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm);
	struct skcipher_walk walk;
	struct chacha_ctx subctx;
	u32 *state, state_buf[16 + 2] __aligned(8);
	u8 real_iv[16];
	int err;

	if (req->cryptlen <= CHACHA_BLOCK_SIZE \|\| !crypto_simd_usable())
	return crypto_xchacha_crypt(req);

	err = skcipher_walk_virt(&walk, req, true);
	if (err)
	return err;

	BUILD_BUG_ON(CHACHA_STATE_ALIGN != 16);
	state = PTR_ALIGN(state_buf + 0, CHACHA_STATE_ALIGN);
	crypto_chacha_init(state, ctx, req->iv);

	kernel_fpu_begin();

	hchacha_block_ssse3(state, subctx.key, ctx->nrounds);
	subctx.nrounds = ctx->nrounds;

	memcpy(&real_iv[0], req->iv + 24, 8);
	memcpy(&real_iv[8], req->iv + 16, 8);
	err = chacha_simd_stream_xor(&walk, &subctx, real_iv);

	kernel_fpu_end();

	return err;
	}

	static struct skcipher_alg algs[] = {
	{
	.base.cra_name = "chacha20",
	.base.cra_driver_name = "chacha20-simd",
	.base.cra_priority = 300,
	.base.cra_blocksize = 1,
	.base.cra_ctxsize = sizeof(struct chacha_ctx),
	.base.cra_module = THIS_MODULE,

	.min_keysize = CHACHA_KEY_SIZE,
	.max_keysize = CHACHA_KEY_SIZE,
	.ivsize = CHACHA_IV_SIZE,
	.chunksize = CHACHA_BLOCK_SIZE,
	.setkey = crypto_chacha20_setkey,
	.encrypt = chacha_simd,
	.decrypt = chacha_simd,
	}, {
	.base.cra_name = "xchacha20",
	.base.cra_driver_name = "xchacha20-simd",
	.base.cra_priority = 300,
	.base.cra_blocksize = 1,
	.base.cra_ctxsize = sizeof(struct chacha_ctx),
	.base.cra_module = THIS_MODULE,

	.min_keysize = CHACHA_KEY_SIZE,
	.max_keysize = CHACHA_KEY_SIZE,
	.ivsize = XCHACHA_IV_SIZE,
	.chunksize = CHACHA_BLOCK_SIZE,
	.setkey = crypto_chacha20_setkey,
	.encrypt = xchacha_simd,
	.decrypt = xchacha_simd,
	}, {
	.base.cra_name = "xchacha12",
	.base.cra_driver_name = "xchacha12-simd",
	.base.cra_priority = 300,
	.base.cra_blocksize = 1,
	.base.cra_ctxsize = sizeof(struct chacha_ctx),
	.base.cra_module = THIS_MODULE,

	.min_keysize = CHACHA_KEY_SIZE,
	.max_keysize = CHACHA_KEY_SIZE,
	.ivsize = XCHACHA_IV_SIZE,
	.chunksize = CHACHA_BLOCK_SIZE,
	.setkey = crypto_chacha12_setkey,
	.encrypt = xchacha_simd,
	.decrypt = xchacha_simd,
	},
	};

	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 crypto_register_skciphers(algs, ARRAY_SIZE(algs));
	}

	static void __exit chacha_simd_mod_fini(void)
	{
	crypto_unregister_skciphers(algs, ARRAY_SIZE(algs));
	}

	module_init(chacha_simd_mod_init);
	module_exit(chacha_simd_mod_fini);

	MODULE_LICENSE("GPL");
	MODULE_AUTHOR("Martin Willi <martin@strongswan.org>");
	MODULE_DESCRIPTION("ChaCha and XChaCha stream ciphers (x64 SIMD accelerated)");
	MODULE_ALIAS_CRYPTO("chacha20");
	MODULE_ALIAS_CRYPTO("chacha20-simd");
	MODULE_ALIAS_CRYPTO("xchacha20");
	MODULE_ALIAS_CRYPTO("xchacha20-simd");
	MODULE_ALIAS_CRYPTO("xchacha12");
	MODULE_ALIAS_CRYPTO("xchacha12-simd");