path: root/arch/sparc/crypto/aes_glue.c

/* Glue code for AES encryption optimized for sparc64 crypto opcodes.
 *
 * This is based largely upon arch/x86/crypto/aesni-intel_glue.c
 *
 * Copyright (C) 2008, Intel Corp.
 *    Author: Huang Ying <ying.huang@intel.com>
 *
 * Added RFC4106 AES-GCM support for 128-bit keys under the AEAD
 * interface for 64-bit kernels.
 *    Authors: Adrian Hoban <adrian.hoban@intel.com>
 *             Gabriele Paoloni <gabriele.paoloni@intel.com>
 *             Tadeusz Struk (tadeusz.struk@intel.com)
 *             Aidan O'Mahony (aidan.o.mahony@intel.com)
 *    Copyright (c) 2010, Intel Corporation.
 */

#include <linux/crypto.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/types.h>
#include <crypto/algapi.h>
#include <crypto/aes.h>

#include <asm/fpumacro.h>
#include <asm/pstate.h>
#include <asm/elf.h>

struct crypto_sparc64_aes_ctx {
	u64 key[AES_MAX_KEYLENGTH / sizeof(u64)];
	u32 key_length;
	u32 expanded_key_length;
};

extern void aes_sparc64_key_expand(const u32 *in_key, u64 *output_key,
				   unsigned int key_len);

static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
		       unsigned int key_len)
{
	struct crypto_sparc64_aes_ctx *ctx = crypto_tfm_ctx(tfm);
	u32 *flags = &tfm->crt_flags;

	switch (key_len) {
	case AES_KEYSIZE_128:
		ctx->expanded_key_length = 0xb0;
		break;

	case AES_KEYSIZE_192:
		ctx->expanded_key_length = 0xd0;
		break;

	case AES_KEYSIZE_256:
		ctx->expanded_key_length = 0xf0;
		break;

	default:
		*flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
		return -EINVAL;
	}

	aes_sparc64_key_expand((const u32 *)in_key, &ctx->key[0], key_len);
	ctx->key_length = key_len;

	return 0;
}

extern void aes_sparc64_encrypt(const u64 *key, const u32 *input,
				u32 *output, unsigned int key_len);

static void aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
	struct crypto_sparc64_aes_ctx *ctx = crypto_tfm_ctx(tfm);

	aes_sparc64_encrypt(&ctx->key[0], (const u32 *) src,
			    (u32 *) dst, ctx->key_length);
}

extern void aes_sparc64_decrypt(const u64 *key, const u32 *input,
				u32 *output, unsigned int key_len,
				unsigned int expanded_key_len);

static void aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
	struct crypto_sparc64_aes_ctx *ctx = crypto_tfm_ctx(tfm);

	aes_sparc64_decrypt(&ctx->key[0], (const u32 *) src,
			    (u32 *) dst, ctx->key_length,
			    ctx->expanded_key_length);
}

extern void aes_sparc64_load_encrypt_keys(u64 *key);
extern void aes_sparc64_load_decrypt_keys(u64 *key);

#define AES_BLOCK_MASK	(~(AES_BLOCK_SIZE-1))

extern void aes_sparc64_ecb_encrypt(u64 *key, const u32 *input, u32 *output,
				    unsigned int key_len, unsigned int len);

static int ecb_encrypt(struct blkcipher_desc *desc,
		       struct scatterlist *dst, struct scatterlist *src,
		       unsigned int nbytes)
{
	struct crypto_sparc64_aes_ctx *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);

	aes_sparc64_load_encrypt_keys(&ctx->key[0]);
	while ((nbytes = walk.nbytes)) {
		unsigned int block_len = nbytes & AES_BLOCK_MASK;

		if (likely(block_len)) {
			aes_sparc64_ecb_encrypt(&ctx->key[0],
						(const u32 *)walk.src.virt.addr,
						(u32 *) walk.dst.virt.addr,
						ctx->key_length, block_len);
		}
		nbytes &= AES_BLOCK_SIZE - 1;
		err = blkcipher_walk_done(desc, &walk, nbytes);
	}
	fprs_write(0);
	return err;
}

extern void aes_sparc64_ecb_decrypt(u64 *ekey, const u32 *input, u32 *output,
				    unsigned int key_len, unsigned int len);

static int ecb_decrypt(struct blkcipher_desc *desc,
		       struct scatterlist *dst, struct scatterlist *src,
		       unsigned int nbytes)
{
	struct crypto_sparc64_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	struct blkcipher_walk walk;
	u64 *key_end;
	int err;

	blkcipher_walk_init(&walk, dst, src, nbytes);
	err = blkcipher_walk_virt(desc, &walk);

	aes_sparc64_load_decrypt_keys(&ctx->key[0]);
	key_end = &ctx->key[ctx->expanded_key_length / sizeof(u64)];
	while ((nbytes = walk.nbytes)) {
		unsigned int block_len = nbytes & AES_BLOCK_MASK;

		aes_sparc64_ecb_decrypt(key_end, (const u32 *) walk.src.virt.addr,
					(u32 *) walk.dst.virt.addr, ctx->key_length,
					block_len);
		nbytes &= AES_BLOCK_SIZE - 1;
		err = blkcipher_walk_done(desc, &walk, nbytes);
	}
	fprs_write(0);

	return err;
}

extern void aes_sparc64_cbc_encrypt(u64 *key, const u32 *input, u32 *output,
				    unsigned int key_len, unsigned int len,
				    u64 *iv);

static int cbc_encrypt(struct blkcipher_desc *desc,
		       struct scatterlist *dst, struct scatterlist *src,
		       unsigned int nbytes)
{
	struct crypto_sparc64_aes_ctx *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);

	aes_sparc64_load_encrypt_keys(&ctx->key[0]);
	while ((nbytes = walk.nbytes)) {
		unsigned int block_len = nbytes & AES_BLOCK_MASK;

		if (likely(block_len)) {
			aes_sparc64_cbc_encrypt(&ctx->key[0],
						(const u32 *)walk.src.virt.addr,
						(u32 *) walk.dst.virt.addr,
						ctx->key_length, block_len,
						(u64 *) walk.iv);
		}
		nbytes &= AES_BLOCK_SIZE - 1;
		err = blkcipher_walk_done(desc, &walk, nbytes);
	}
	fprs_write(0);
	return err;
}

extern void aes_sparc64_cbc_decrypt(u64 *ekey, unsigned int key_len,
				    const u32 *input, u32 *output,
				    unsigned int len, u64 *iv);

static int cbc_decrypt(struct blkcipher_desc *desc,
		       struct scatterlist *dst, struct scatterlist *src,
		       unsigned int nbytes)
{
	struct crypto_sparc64_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	struct blkcipher_walk walk;
	u64 *key_end;
	int err;

	blkcipher_walk_init(&walk, dst, src, nbytes);
	err = blkcipher_walk_virt(desc, &walk);

	aes_sparc64_load_decrypt_keys(&ctx->key[0]);
	key_end = &ctx->key[ctx->expanded_key_length / sizeof(u64)];
	while ((nbytes = walk.nbytes)) {
		unsigned int block_len = nbytes & AES_BLOCK_MASK;

		aes_sparc64_cbc_decrypt(key_end, ctx->key_length,
					(const u32 *) walk.src.virt.addr,
					(u32 *) walk.dst.virt.addr,
					block_len, (u64 *) walk.iv);
		nbytes &= AES_BLOCK_SIZE - 1;
		err = blkcipher_walk_done(desc, &walk, nbytes);
	}
	fprs_write(0);

	return err;
}

static struct crypto_alg algs[] = { {
	.cra_name		= "aes",
	.cra_driver_name	= "aes-sparc64",
	.cra_priority		= 150,
	.cra_flags		= CRYPTO_ALG_TYPE_CIPHER,
	.cra_blocksize		= AES_BLOCK_SIZE,
	.cra_ctxsize		= sizeof(struct crypto_sparc64_aes_ctx),
	.cra_alignmask		= 3,
	.cra_module		= THIS_MODULE,
	.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
		}
	}
}, {
	.cra_name		= "ecb(aes)",
	.cra_driver_name	= "ecb-aes-sparc64",
	.cra_priority		= 150,
	.cra_flags		= CRYPTO_ALG_TYPE_BLKCIPHER,
	.cra_blocksize		= AES_BLOCK_SIZE,
	.cra_ctxsize		= sizeof(struct crypto_sparc64_aes_ctx),
	.cra_alignmask		= 7,
	.cra_type		= &crypto_blkcipher_type,
	.cra_module		= THIS_MODULE,
	.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,
		},
	},
}, {
	.cra_name		= "cbc(aes)",
	.cra_driver_name	= "cbc-aes-sparc64",
	.cra_priority		= 150,
	.cra_flags		= CRYPTO_ALG_TYPE_BLKCIPHER,
	.cra_blocksize		= AES_BLOCK_SIZE,
	.cra_ctxsize		= sizeof(struct crypto_sparc64_aes_ctx),
	.cra_alignmask		= 7,
	.cra_type		= &crypto_blkcipher_type,
	.cra_module		= THIS_MODULE,
	.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 bool __init sparc64_has_aes_opcode(void)
{
	unsigned long cfr;

	if (!(sparc64_elf_hwcap & HWCAP_SPARC_CRYPTO))
		return false;

	__asm__ __volatile__("rd %%asr26, %0" : "=r" (cfr));
	if (!(cfr & CFR_AES))
		return false;

	return true;
}

static int __init aes_sparc64_mod_init(void)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(algs); i++)
		INIT_LIST_HEAD(&algs[i].cra_list);

	if (sparc64_has_aes_opcode()) {
		pr_info("Using sparc64 aes opcodes optimized AES implementation\n");
		return crypto_register_algs(algs, ARRAY_SIZE(algs));
	}
	pr_info("sparc64 aes opcodes not available.\n");
	return -ENODEV;
}

static void __exit aes_sparc64_mod_fini(void)
{
	crypto_unregister_algs(algs, ARRAY_SIZE(algs));
}

module_init(aes_sparc64_mod_init);
module_exit(aes_sparc64_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("AES Secure Hash Algorithm, sparc64 aes opcode accelerated");

MODULE_ALIAS("aes");