crypto: aes-ni - Add support to Intel AES-NI instructions for x86_64 platform

Intel AES-NI is a new set of Single Instruction Multiple Data (SIMD)
instructions that are going to be introduced in the next generation of
Intel processor, as of 2009. These instructions enable fast and secure
data encryption and decryption, using the Advanced Encryption Standard
(AES), defined by FIPS Publication number 197.  The architecture
introduces six instructions that offer full hardware support for
AES. Four of them support high performance data encryption and
decryption, and the other two instructions support the AES key
expansion procedure.

The white paper can be downloaded from:

http://softwarecommunity.intel.com/isn/downloads/intelavx/AES-Instructions-Set_WP.pdf

AES may be used in soft_irq context, but MMX/SSE context can not be
touched safely in soft_irq context. So in_interrupt() is checked, if
in IRQ or soft_irq context, the general x86_64 implementation are used
instead.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 461 insertions, 0 deletions

diff --git a/arch/x86/crypto/aesni-intel_glue.c b/arch/x86/crypto/aesni-intel_glue.c
new file mode 100644
index 00000000000..02af0af6549
--- /dev/null
+++ b/arch/x86/crypto/aesni-intel_glue.c
@@ -0,0 +1,461 @@
+/*
+ * Support for Intel AES-NI instructions. This file contains glue
+ * code, the real AES implementation is in intel-aes_asm.S.
+ *
+ * Copyright (C) 2008, Intel Corp.
+ *    Author: Huang Ying <ying.huang@intel.com>
+ *
+ * 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 <linux/hardirq.h>
+#include <linux/types.h>
+#include <linux/crypto.h>
+#include <linux/err.h>
+#include <crypto/algapi.h>
+#include <crypto/aes.h>
+#include <crypto/cryptd.h>
+#include <asm/i387.h>
+#include <asm/aes.h>
+
+struct async_aes_ctx {
+	struct cryptd_ablkcipher *cryptd_tfm;
+};
+
+#define AESNI_ALIGN	16
+#define AES_BLOCK_MASK	(~(AES_BLOCK_SIZE-1))
+
+asmlinkage int aesni_set_key(struct crypto_aes_ctx *ctx, const u8 *in_key,
+			     unsigned int key_len);
+asmlinkage void aesni_enc(struct crypto_aes_ctx *ctx, u8 *out,
+			  const u8 *in);
+asmlinkage void aesni_dec(struct crypto_aes_ctx *ctx, u8 *out,
+			  const u8 *in);
+asmlinkage void aesni_ecb_enc(struct crypto_aes_ctx *ctx, u8 *out,
+			      const u8 *in, unsigned int len);
+asmlinkage void aesni_ecb_dec(struct crypto_aes_ctx *ctx, u8 *out,
+			      const u8 *in, unsigned int len);
+asmlinkage void aesni_cbc_enc(struct crypto_aes_ctx *ctx, u8 *out,
+			      const u8 *in, unsigned int len, u8 *iv);
+asmlinkage void aesni_cbc_dec(struct crypto_aes_ctx *ctx, u8 *out,
+			      const u8 *in, unsigned int len, u8 *iv);
+
+static inline int kernel_fpu_using(void)
+{
+	if (in_interrupt() && !(read_cr0() & X86_CR0_TS))
+		return 1;
+	return 0;
+}
+
+static inline struct crypto_aes_ctx *aes_ctx(void *raw_ctx)
+{
+	unsigned long addr = (unsigned long)raw_ctx;
+	unsigned long align = AESNI_ALIGN;
+
+	if (align <= crypto_tfm_ctx_alignment())
+		align = 1;
+	return (struct crypto_aes_ctx *)ALIGN(addr, align);
+}
+
+static int aes_set_key_common(struct crypto_tfm *tfm, void *raw_ctx,
+			      const u8 *in_key, unsigned int key_len)
+{
+	struct crypto_aes_ctx *ctx = aes_ctx(raw_ctx);
+	u32 *flags = &tfm->crt_flags;
+	int err;
+
+	if (key_len != AES_KEYSIZE_128 && key_len != AES_KEYSIZE_192 &&
+	    key_len != AES_KEYSIZE_256) {
+		*flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
+		return -EINVAL;
+	}
+
+	if (kernel_fpu_using())
+		err = crypto_aes_expand_key(ctx, in_key, key_len);
+	else {
+		kernel_fpu_begin();
+		err = aesni_set_key(ctx, in_key, key_len);
+		kernel_fpu_end();
+	}
+
+	return err;
+}
+
+static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
+		       unsigned int key_len)
+{
+	return aes_set_key_common(tfm, crypto_tfm_ctx(tfm), in_key, key_len);
+}
+
+static void aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
+{
+	struct crypto_aes_ctx *ctx = aes_ctx(crypto_tfm_ctx(tfm));
+
+	if (kernel_fpu_using())
+		crypto_aes_encrypt_x86(ctx, dst, src);
+	else {
+		kernel_fpu_begin();
+		aesni_enc(ctx, dst, src);
+		kernel_fpu_end();
+	}
+}
+
+static void aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
+{
+	struct crypto_aes_ctx *ctx = aes_ctx(crypto_tfm_ctx(tfm));
+
+	if (kernel_fpu_using())
+		crypto_aes_decrypt_x86(ctx, dst, src);
+	else {
+		kernel_fpu_begin();
+		aesni_dec(ctx, dst, src);
+		kernel_fpu_end();
+	}
+}
+
+static struct crypto_alg aesni_alg = {
+	.cra_name		= "aes",
+	.cra_driver_name	= "aes-aesni",
+	.cra_priority		= 300,
+	.cra_flags		= CRYPTO_ALG_TYPE_CIPHER,
+	.cra_blocksize		= AES_BLOCK_SIZE,
+	.cra_ctxsize		= sizeof(struct crypto_aes_ctx)+AESNI_ALIGN-1,
+	.cra_alignmask		= 0,
+	.cra_module		= THIS_MODULE,
+	.cra_list		= LIST_HEAD_INIT(aesni_alg.cra_list),
+	.cra_u	= {
+		.cipher	= {
+			.cia_min_keysize	= AES_MIN_KEY_SIZE,
+			.cia_max_keysize	= AES_MAX_KEY_SIZE,
+			.cia_setkey		= aes_set_key,
+			.cia_encrypt		= aes_encrypt,
+			.cia_decrypt		= aes_decrypt
+		}
+	}
+};
+
+static int ecb_encrypt(struct blkcipher_desc *desc,
+		       struct scatterlist *dst, struct scatterlist *src,
+		       unsigned int nbytes)
+{
+	struct crypto_aes_ctx *ctx = aes_ctx(crypto_blkcipher_ctx(desc->tfm));
+	struct blkcipher_walk walk;
+	int err;
+
+	blkcipher_walk_init(&walk, dst, src, nbytes);
+	err = blkcipher_walk_virt(desc, &walk);
+
+	kernel_fpu_begin();
+	while ((nbytes = walk.nbytes)) {
+		aesni_ecb_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr,
+			      nbytes & AES_BLOCK_MASK);
+		nbytes &= AES_BLOCK_SIZE - 1;
+		err = blkcipher_walk_done(desc, &walk, nbytes);
+	}
+	kernel_fpu_end();
+
+	return err;
+}
+
+static int ecb_decrypt(struct blkcipher_desc *desc,
+		       struct scatterlist *dst, struct scatterlist *src,
+		       unsigned int nbytes)
+{
+	struct crypto_aes_ctx *ctx = aes_ctx(crypto_blkcipher_ctx(desc->tfm));
+	struct blkcipher_walk walk;
+	int err;
+
+	blkcipher_walk_init(&walk, dst, src, nbytes);
+	err = blkcipher_walk_virt(desc, &walk);
+
+	kernel_fpu_begin();
+	while ((nbytes = walk.nbytes)) {
+		aesni_ecb_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr,
+			      nbytes & AES_BLOCK_MASK);
+		nbytes &= AES_BLOCK_SIZE - 1;
+		err = blkcipher_walk_done(desc, &walk, nbytes);
+	}
+	kernel_fpu_end();
+
+	return err;
+}
+
+static struct crypto_alg blk_ecb_alg = {
+	.cra_name		= "__ecb-aes-aesni",
+	.cra_driver_name	= "__driver-ecb-aes-aesni",
+	.cra_priority		= 0,
+	.cra_flags		= CRYPTO_ALG_TYPE_BLKCIPHER,
+	.cra_blocksize		= AES_BLOCK_SIZE,
+	.cra_ctxsize		= sizeof(struct crypto_aes_ctx)+AESNI_ALIGN-1,
+	.cra_alignmask		= 0,
+	.cra_type		= &crypto_blkcipher_type,
+	.cra_module		= THIS_MODULE,
+	.cra_list		= LIST_HEAD_INIT(blk_ecb_alg.cra_list),
+	.cra_u = {
+		.blkcipher = {
+			.min_keysize	= AES_MIN_KEY_SIZE,
+			.max_keysize	= AES_MAX_KEY_SIZE,
+			.setkey		= aes_set_key,
+			.encrypt	= ecb_encrypt,
+			.decrypt	= ecb_decrypt,
+		},
+	},
+};
+
+static int cbc_encrypt(struct blkcipher_desc *desc,
+		       struct scatterlist *dst, struct scatterlist *src,
+		       unsigned int nbytes)
+{
+	struct crypto_aes_ctx *ctx = aes_ctx(crypto_blkcipher_ctx(desc->tfm));
+	struct blkcipher_walk walk;
+	int err;
+
+	blkcipher_walk_init(&walk, dst, src, nbytes);
+	err = blkcipher_walk_virt(desc, &walk);
+
+	kernel_fpu_begin();
+	while ((nbytes = walk.nbytes)) {
+		aesni_cbc_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr,
+			      nbytes & AES_BLOCK_MASK, walk.iv);
+		nbytes &= AES_BLOCK_SIZE - 1;
+		err = blkcipher_walk_done(desc, &walk, nbytes);
+	}
+	kernel_fpu_end();
+
+	return err;
+}
+
+static int cbc_decrypt(struct blkcipher_desc *desc,
+		       struct scatterlist *dst, struct scatterlist *src,
+		       unsigned int nbytes)
+{
+	struct crypto_aes_ctx *ctx = aes_ctx(crypto_blkcipher_ctx(desc->tfm));
+	struct blkcipher_walk walk;
+	int err;
+
+	blkcipher_walk_init(&walk, dst, src, nbytes);
+	err = blkcipher_walk_virt(desc, &walk);
+
+	kernel_fpu_begin();
+	while ((nbytes = walk.nbytes)) {
+		aesni_cbc_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr,
+			      nbytes & AES_BLOCK_MASK, walk.iv);
+		nbytes &= AES_BLOCK_SIZE - 1;
+		err = blkcipher_walk_done(desc, &walk, nbytes);
+	}
+	kernel_fpu_end();
+
+	return err;
+}
+
+static struct crypto_alg blk_cbc_alg = {
+	.cra_name		= "__cbc-aes-aesni",
+	.cra_driver_name	= "__driver-cbc-aes-aesni",
+	.cra_priority		= 0,
+	.cra_flags		= CRYPTO_ALG_TYPE_BLKCIPHER,
+	.cra_blocksize		= AES_BLOCK_SIZE,
+	.cra_ctxsize		= sizeof(struct crypto_aes_ctx)+AESNI_ALIGN-1,
+	.cra_alignmask		= 0,
+	.cra_type		= &crypto_blkcipher_type,
+	.cra_module		= THIS_MODULE,
+	.cra_list		= LIST_HEAD_INIT(blk_cbc_alg.cra_list),
+	.cra_u = {
+		.blkcipher = {
+			.min_keysize	= AES_MIN_KEY_SIZE,
+			.max_keysize	= AES_MAX_KEY_SIZE,
+			.setkey		= aes_set_key,
+			.encrypt	= cbc_encrypt,
+			.decrypt	= cbc_decrypt,
+		},
+	},
+};
+
+static int ablk_set_key(struct crypto_ablkcipher *tfm, const u8 *key,
+			unsigned int key_len)
+{
+	struct async_aes_ctx *ctx = crypto_ablkcipher_ctx(tfm);
+
+	return crypto_ablkcipher_setkey(&ctx->cryptd_tfm->base, key, key_len);
+}
+
+static int ablk_encrypt(struct ablkcipher_request *req)
+{
+	struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
+	struct async_aes_ctx *ctx = crypto_ablkcipher_ctx(tfm);
+
+	if (kernel_fpu_using()) {
+		struct ablkcipher_request *cryptd_req =
+			ablkcipher_request_ctx(req);
+		memcpy(cryptd_req, req, sizeof(*req));
+		ablkcipher_request_set_tfm(cryptd_req, &ctx->cryptd_tfm->base);
+		return crypto_ablkcipher_encrypt(cryptd_req);
+	} else {
+		struct blkcipher_desc desc;
+		desc.tfm = cryptd_ablkcipher_child(ctx->cryptd_tfm);
+		desc.info = req->info;
+		desc.flags = 0;
+		return crypto_blkcipher_crt(desc.tfm)->encrypt(
+			&desc, req->dst, req->src, req->nbytes);
+	}
+}
+
+static int ablk_decrypt(struct ablkcipher_request *req)
+{
+	struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
+	struct async_aes_ctx *ctx = crypto_ablkcipher_ctx(tfm);
+
+	if (kernel_fpu_using()) {
+		struct ablkcipher_request *cryptd_req =
+			ablkcipher_request_ctx(req);
+		memcpy(cryptd_req, req, sizeof(*req));
+		ablkcipher_request_set_tfm(cryptd_req, &ctx->cryptd_tfm->base);
+		return crypto_ablkcipher_decrypt(cryptd_req);
+	} else {
+		struct blkcipher_desc desc;
+		desc.tfm = cryptd_ablkcipher_child(ctx->cryptd_tfm);
+		desc.info = req->info;
+		desc.flags = 0;
+		return crypto_blkcipher_crt(desc.tfm)->decrypt(
+			&desc, req->dst, req->src, req->nbytes);
+	}
+}
+
+static void ablk_exit(struct crypto_tfm *tfm)
+{
+	struct async_aes_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	cryptd_free_ablkcipher(ctx->cryptd_tfm);
+}
+
+static void ablk_init_common(struct crypto_tfm *tfm,
+			     struct cryptd_ablkcipher *cryptd_tfm)
+{
+	struct async_aes_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	ctx->cryptd_tfm = cryptd_tfm;
+	tfm->crt_ablkcipher.reqsize = sizeof(struct ablkcipher_request) +
+		crypto_ablkcipher_reqsize(&cryptd_tfm->base);
+}
+
+static int ablk_ecb_init(struct crypto_tfm *tfm)
+{
+	struct cryptd_ablkcipher *cryptd_tfm;
+
+	cryptd_tfm = cryptd_alloc_ablkcipher("__driver-ecb-aes-aesni", 0, 0);
+	if (IS_ERR(cryptd_tfm))
+		return PTR_ERR(cryptd_tfm);
+	ablk_init_common(tfm, cryptd_tfm);
+	return 0;
+}
+
+static struct crypto_alg ablk_ecb_alg = {
+	.cra_name		= "ecb(aes)",
+	.cra_driver_name	= "ecb-aes-aesni",
+	.cra_priority		= 400,
+	.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
+	.cra_blocksize		= AES_BLOCK_SIZE,
+	.cra_ctxsize		= sizeof(struct async_aes_ctx),
+	.cra_alignmask		= 0,
+	.cra_type		= &crypto_ablkcipher_type,
+	.cra_module		= THIS_MODULE,
+	.cra_list		= LIST_HEAD_INIT(ablk_ecb_alg.cra_list),
+	.cra_init		= ablk_ecb_init,
+	.cra_exit		= ablk_exit,
+	.cra_u = {
+		.ablkcipher = {
+			.min_keysize	= AES_MIN_KEY_SIZE,
+			.max_keysize	= AES_MAX_KEY_SIZE,
+			.setkey		= ablk_set_key,
+			.encrypt	= ablk_encrypt,
+			.decrypt	= ablk_decrypt,
+		},
+	},
+};
+
+static int ablk_cbc_init(struct crypto_tfm *tfm)
+{
+	struct cryptd_ablkcipher *cryptd_tfm;
+
+	cryptd_tfm = cryptd_alloc_ablkcipher("__driver-cbc-aes-aesni", 0, 0);
+	if (IS_ERR(cryptd_tfm))
+		return PTR_ERR(cryptd_tfm);
+	ablk_init_common(tfm, cryptd_tfm);
+	return 0;
+}
+
+static struct crypto_alg ablk_cbc_alg = {
+	.cra_name		= "cbc(aes)",
+	.cra_driver_name	= "cbc-aes-aesni",
+	.cra_priority		= 400,
+	.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
+	.cra_blocksize		= AES_BLOCK_SIZE,
+	.cra_ctxsize		= sizeof(struct async_aes_ctx),
+	.cra_alignmask		= 0,
+	.cra_type		= &crypto_ablkcipher_type,
+	.cra_module		= THIS_MODULE,
+	.cra_list		= LIST_HEAD_INIT(ablk_cbc_alg.cra_list),
+	.cra_init		= ablk_cbc_init,
+	.cra_exit		= ablk_exit,
+	.cra_u = {
+		.ablkcipher = {
+			.min_keysize	= AES_MIN_KEY_SIZE,
+			.max_keysize	= AES_MAX_KEY_SIZE,
+			.ivsize		= AES_BLOCK_SIZE,
+			.setkey		= ablk_set_key,
+			.encrypt	= ablk_encrypt,
+			.decrypt	= ablk_decrypt,
+		},
+	},
+};
+
+static int __init aesni_init(void)
+{
+	int err;
+
+	if (!cpu_has_aes) {
+		printk(KERN_ERR "Intel AES-NI instructions are not detected.\n");
+		return -ENODEV;
+	}
+	if ((err = crypto_register_alg(&aesni_alg)))
+		goto aes_err;
+	if ((err = crypto_register_alg(&blk_ecb_alg)))
+		goto blk_ecb_err;
+	if ((err = crypto_register_alg(&blk_cbc_alg)))
+		goto blk_cbc_err;
+	if ((err = crypto_register_alg(&ablk_ecb_alg)))
+		goto ablk_ecb_err;
+	if ((err = crypto_register_alg(&ablk_cbc_alg)))
+		goto ablk_cbc_err;
+
+	return err;
+
+ablk_cbc_err:
+	crypto_unregister_alg(&ablk_ecb_alg);
+ablk_ecb_err:
+	crypto_unregister_alg(&blk_cbc_alg);
+blk_cbc_err:
+	crypto_unregister_alg(&blk_ecb_alg);
+blk_ecb_err:
+	crypto_unregister_alg(&aesni_alg);
+aes_err:
+	return err;
+}
+
+static void __exit aesni_exit(void)
+{
+	crypto_unregister_alg(&ablk_cbc_alg);
+	crypto_unregister_alg(&ablk_ecb_alg);
+	crypto_unregister_alg(&blk_cbc_alg);
+	crypto_unregister_alg(&blk_ecb_alg);
+	crypto_unregister_alg(&aesni_alg);
+}
+
+module_init(aesni_init);
+module_exit(aesni_exit);
+
+MODULE_DESCRIPTION("Rijndael (AES) Cipher Algorithm, Intel AES-NI instructions optimized");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("aes");