[deliverable/linux.git] / arch / powerpc / crypto / aes-spe-glue.c

/*
 * Glue code for AES implementation for SPE instructions (PPC)
 *
 * Based on generic implementation. The assembler module takes care
 * about the SPE registers so it can run from interrupt context.
 *
 * Copyright (c) 2015 Markus Stockhausen <stockhausen@collogia.de>
 *
 * 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 <crypto/aes.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/crypto.h>
#include <asm/byteorder.h>
#include <asm/switch_to.h>
#include <crypto/algapi.h>

/*
 * MAX_BYTES defines the number of bytes that are allowed to be processed
 * between preempt_disable() and preempt_enable(). e500 cores can issue two
 * instructions per clock cycle using one 32/64 bit unit (SU1) and one 32
 * bit unit (SU2). One of these can be a memory access that is executed via
 * a single load and store unit (LSU). XTS-AES-256 takes ~780 operations per
 * 16 byte block block or 25 cycles per byte. Thus 768 bytes of input data
 * will need an estimated maximum of 20,000 cycles. Headroom for cache misses
 * included. Even with the low end model clocked at 667 MHz this equals to a
 * critical time window of less than 30us. The value has been choosen to
 * process a 512 byte disk block in one or a large 1400 bytes IPsec network
 * packet in two runs.
 *
 */
#define MAX_BYTES 768

struct ppc_aes_ctx {
	u32 key_enc[AES_MAX_KEYLENGTH_U32];
	u32 key_dec[AES_MAX_KEYLENGTH_U32];
	u32 rounds;
};

struct ppc_xts_ctx {
	u32 key_enc[AES_MAX_KEYLENGTH_U32];
	u32 key_dec[AES_MAX_KEYLENGTH_U32];
	u32 key_twk[AES_MAX_KEYLENGTH_U32];
	u32 rounds;
};

extern void ppc_encrypt_aes(u8 *out, const u8 *in, u32 *key_enc, u32 rounds);
extern void ppc_decrypt_aes(u8 *out, const u8 *in, u32 *key_dec, u32 rounds);
extern void ppc_encrypt_ecb(u8 *out, const u8 *in, u32 *key_enc, u32 rounds,
			    u32 bytes);
extern void ppc_decrypt_ecb(u8 *out, const u8 *in, u32 *key_dec, u32 rounds,
			    u32 bytes);
extern void ppc_encrypt_cbc(u8 *out, const u8 *in, u32 *key_enc, u32 rounds,
			    u32 bytes, u8 *iv);
extern void ppc_decrypt_cbc(u8 *out, const u8 *in, u32 *key_dec, u32 rounds,
			    u32 bytes, u8 *iv);
extern void ppc_crypt_ctr  (u8 *out, const u8 *in, u32 *key_enc, u32 rounds,
			    u32 bytes, u8 *iv);
extern void ppc_encrypt_xts(u8 *out, const u8 *in, u32 *key_enc, u32 rounds,
			    u32 bytes, u8 *iv, u32 *key_twk);
extern void ppc_decrypt_xts(u8 *out, const u8 *in, u32 *key_dec, u32 rounds,
			    u32 bytes, u8 *iv, u32 *key_twk);

extern void ppc_expand_key_128(u32 *key_enc, const u8 *key);
extern void ppc_expand_key_192(u32 *key_enc, const u8 *key);
extern void ppc_expand_key_256(u32 *key_enc, const u8 *key);

extern void ppc_generate_decrypt_key(u32 *key_dec,u32 *key_enc,
				     unsigned int key_len);

static void spe_begin(void)
{
	/* disable preemption and save users SPE registers if required */
	preempt_disable();
	enable_kernel_spe();
}

static void spe_end(void)
{
	disable_kernel_spe();
	/* reenable preemption */
	preempt_enable();
}

static int ppc_aes_setkey(struct crypto_tfm *tfm, const u8 *in_key,
		unsigned int key_len)
{
	struct ppc_aes_ctx *ctx = crypto_tfm_ctx(tfm);

	if (key_len != AES_KEYSIZE_128 &&
	    key_len != AES_KEYSIZE_192 &&
	    key_len != AES_KEYSIZE_256) {
		tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
		return -EINVAL;
	}

	switch (key_len) {
	case AES_KEYSIZE_128:
		ctx->rounds = 4;
		ppc_expand_key_128(ctx->key_enc, in_key);
		break;
	case AES_KEYSIZE_192:
		ctx->rounds = 5;
		ppc_expand_key_192(ctx->key_enc, in_key);
		break;
	case AES_KEYSIZE_256:
		ctx->rounds = 6;
		ppc_expand_key_256(ctx->key_enc, in_key);
		break;
	}

	ppc_generate_decrypt_key(ctx->key_dec, ctx->key_enc, key_len);

	return 0;
}

static int ppc_xts_setkey(struct crypto_tfm *tfm, const u8 *in_key,
		   unsigned int key_len)
{
	struct ppc_xts_ctx *ctx = crypto_tfm_ctx(tfm);

	key_len >>= 1;

	if (key_len != AES_KEYSIZE_128 &&
	    key_len != AES_KEYSIZE_192 &&
	    key_len != AES_KEYSIZE_256) {
		tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
		return -EINVAL;
	}

	switch (key_len) {
	case AES_KEYSIZE_128:
		ctx->rounds = 4;
		ppc_expand_key_128(ctx->key_enc, in_key);
		ppc_expand_key_128(ctx->key_twk, in_key + AES_KEYSIZE_128);
		break;
	case AES_KEYSIZE_192:
		ctx->rounds = 5;
		ppc_expand_key_192(ctx->key_enc, in_key);
		ppc_expand_key_192(ctx->key_twk, in_key + AES_KEYSIZE_192);
		break;
	case AES_KEYSIZE_256:
		ctx->rounds = 6;
		ppc_expand_key_256(ctx->key_enc, in_key);
		ppc_expand_key_256(ctx->key_twk, in_key + AES_KEYSIZE_256);
		break;
	}

	ppc_generate_decrypt_key(ctx->key_dec, ctx->key_enc, key_len);

	return 0;
}

static void ppc_aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
{
	struct ppc_aes_ctx *ctx = crypto_tfm_ctx(tfm);

	spe_begin();
	ppc_encrypt_aes(out, in, ctx->key_enc, ctx->rounds);
	spe_end();
}

static void ppc_aes_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
{
	struct ppc_aes_ctx *ctx = crypto_tfm_ctx(tfm);

	spe_begin();
	ppc_decrypt_aes(out, in, ctx->key_dec, ctx->rounds);
	spe_end();
}

static int ppc_ecb_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
			   struct scatterlist *src, unsigned int nbytes)
{
	struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	struct blkcipher_walk walk;
	unsigned int ubytes;
	int err;

	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
	blkcipher_walk_init(&walk, dst, src, nbytes);
	err = blkcipher_walk_virt(desc, &walk);

	while ((nbytes = walk.nbytes)) {
		ubytes = nbytes > MAX_BYTES ?
			 nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
		nbytes -= ubytes;

		spe_begin();
		ppc_encrypt_ecb(walk.dst.virt.addr, walk.src.virt.addr,
				ctx->key_enc, ctx->rounds, nbytes);
		spe_end();

		err = blkcipher_walk_done(desc, &walk, ubytes);
	}

	return err;
}

static int ppc_ecb_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
			   struct scatterlist *src, unsigned int nbytes)
{
	struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	struct blkcipher_walk walk;
	unsigned int ubytes;
	int err;

	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
	blkcipher_walk_init(&walk, dst, src, nbytes);
	err = blkcipher_walk_virt(desc, &walk);

	while ((nbytes = walk.nbytes)) {
		ubytes = nbytes > MAX_BYTES ?
			 nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
		nbytes -= ubytes;

		spe_begin();
		ppc_decrypt_ecb(walk.dst.virt.addr, walk.src.virt.addr,
				ctx->key_dec, ctx->rounds, nbytes);
		spe_end();

		err = blkcipher_walk_done(desc, &walk, ubytes);
	}

	return err;
}

static int ppc_cbc_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
			   struct scatterlist *src, unsigned int nbytes)
{
	struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	struct blkcipher_walk walk;
	unsigned int ubytes;
	int err;

	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
	blkcipher_walk_init(&walk, dst, src, nbytes);
	err = blkcipher_walk_virt(desc, &walk);

	while ((nbytes = walk.nbytes)) {
		ubytes = nbytes > MAX_BYTES ?
			 nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
		nbytes -= ubytes;

		spe_begin();
		ppc_encrypt_cbc(walk.dst.virt.addr, walk.src.virt.addr,
				ctx->key_enc, ctx->rounds, nbytes, walk.iv);
		spe_end();

		err = blkcipher_walk_done(desc, &walk, ubytes);
	}

	return err;
}

static int ppc_cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
			   struct scatterlist *src, unsigned int nbytes)
{
	struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	struct blkcipher_walk walk;
	unsigned int ubytes;
	int err;

	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
	blkcipher_walk_init(&walk, dst, src, nbytes);
	err = blkcipher_walk_virt(desc, &walk);

	while ((nbytes = walk.nbytes)) {
		ubytes = nbytes > MAX_BYTES ?
			 nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
		nbytes -= ubytes;

		spe_begin();
		ppc_decrypt_cbc(walk.dst.virt.addr, walk.src.virt.addr,
				ctx->key_dec, ctx->rounds, nbytes, walk.iv);
		spe_end();

		err = blkcipher_walk_done(desc, &walk, ubytes);
	}

	return err;
}

static int ppc_ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
			 struct scatterlist *src, unsigned int nbytes)
{
	struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	struct blkcipher_walk walk;
	unsigned int pbytes, ubytes;
	int err;

	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
	blkcipher_walk_init(&walk, dst, src, nbytes);
	err = blkcipher_walk_virt_block(desc, &walk, AES_BLOCK_SIZE);

	while ((pbytes = walk.nbytes)) {
		pbytes = pbytes > MAX_BYTES ? MAX_BYTES : pbytes;
		pbytes = pbytes == nbytes ?
			 nbytes : pbytes & ~(AES_BLOCK_SIZE - 1);
		ubytes = walk.nbytes - pbytes;

		spe_begin();
		ppc_crypt_ctr(walk.dst.virt.addr, walk.src.virt.addr,
			      ctx->key_enc, ctx->rounds, pbytes , walk.iv);
		spe_end();

		nbytes -= pbytes;
		err = blkcipher_walk_done(desc, &walk, ubytes);
	}

	return err;
}

static int ppc_xts_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
			   struct scatterlist *src, unsigned int nbytes)
{
	struct ppc_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	struct blkcipher_walk walk;
	unsigned int ubytes;
	int err;
	u32 *twk;

	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
	blkcipher_walk_init(&walk, dst, src, nbytes);
	err = blkcipher_walk_virt(desc, &walk);
	twk = ctx->key_twk;

	while ((nbytes = walk.nbytes)) {
		ubytes = nbytes > MAX_BYTES ?
			 nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
		nbytes -= ubytes;

		spe_begin();
		ppc_encrypt_xts(walk.dst.virt.addr, walk.src.virt.addr,
				ctx->key_enc, ctx->rounds, nbytes, walk.iv, twk);
		spe_end();

		twk = NULL;
		err = blkcipher_walk_done(desc, &walk, ubytes);
	}

	return err;
}

static int ppc_xts_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
			   struct scatterlist *src, unsigned int nbytes)
{
	struct ppc_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	struct blkcipher_walk walk;
	unsigned int ubytes;
	int err;
	u32 *twk;

	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
	blkcipher_walk_init(&walk, dst, src, nbytes);
	err = blkcipher_walk_virt(desc, &walk);
	twk = ctx->key_twk;

	while ((nbytes = walk.nbytes)) {
		ubytes = nbytes > MAX_BYTES ?
			 nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
		nbytes -= ubytes;

		spe_begin();
		ppc_decrypt_xts(walk.dst.virt.addr, walk.src.virt.addr,
				ctx->key_dec, ctx->rounds, nbytes, walk.iv, twk);
		spe_end();

		twk = NULL;
		err = blkcipher_walk_done(desc, &walk, ubytes);
	}

	return err;
}

/*
 * Algorithm definitions. Disabling alignment (cra_alignmask=0) was chosen
 * because the e500 platform can handle unaligned reads/writes very efficently.
 * This improves IPsec thoughput by another few percent. Additionally we assume
 * that AES context is always aligned to at least 8 bytes because it is created
 * with kmalloc() in the crypto infrastructure
 *
 */
static struct crypto_alg aes_algs[] = { {
	.cra_name		=	"aes",
	.cra_driver_name	=	"aes-ppc-spe",
	.cra_priority		=	300,
	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
	.cra_blocksize		=	AES_BLOCK_SIZE,
	.cra_ctxsize		=	sizeof(struct ppc_aes_ctx),
	.cra_alignmask		=	0,
	.cra_module		=	THIS_MODULE,
	.cra_u			=	{
		.cipher = {
			.cia_min_keysize	=	AES_MIN_KEY_SIZE,
			.cia_max_keysize	=	AES_MAX_KEY_SIZE,
			.cia_setkey		=	ppc_aes_setkey,
			.cia_encrypt		=	ppc_aes_encrypt,
			.cia_decrypt		=	ppc_aes_decrypt
		}
	}
}, {
	.cra_name		=	"ecb(aes)",
	.cra_driver_name	=	"ecb-ppc-spe",
	.cra_priority		=	300,
	.cra_flags		=	CRYPTO_ALG_TYPE_BLKCIPHER,
	.cra_blocksize		=	AES_BLOCK_SIZE,
	.cra_ctxsize		=	sizeof(struct ppc_aes_ctx),
	.cra_alignmask		=	0,
	.cra_type		=	&crypto_blkcipher_type,
	.cra_module		=	THIS_MODULE,
	.cra_u = {
		.blkcipher = {
			.min_keysize		=	AES_MIN_KEY_SIZE,
			.max_keysize		=	AES_MAX_KEY_SIZE,
			.ivsize			=	AES_BLOCK_SIZE,
			.setkey			=	ppc_aes_setkey,
			.encrypt		=	ppc_ecb_encrypt,
			.decrypt		=	ppc_ecb_decrypt,
		}
	}
}, {
	.cra_name		=	"cbc(aes)",
	.cra_driver_name	=	"cbc-ppc-spe",
	.cra_priority		=	300,
	.cra_flags		=	CRYPTO_ALG_TYPE_BLKCIPHER,
	.cra_blocksize		=	AES_BLOCK_SIZE,
	.cra_ctxsize		=	sizeof(struct ppc_aes_ctx),
	.cra_alignmask		=	0,
	.cra_type		=	&crypto_blkcipher_type,
	.cra_module		=	THIS_MODULE,
	.cra_u = {
		.blkcipher = {
			.min_keysize		=	AES_MIN_KEY_SIZE,
			.max_keysize		=	AES_MAX_KEY_SIZE,
			.ivsize			=	AES_BLOCK_SIZE,
			.setkey			=	ppc_aes_setkey,
			.encrypt		=	ppc_cbc_encrypt,
			.decrypt		=	ppc_cbc_decrypt,
		}
	}
}, {
	.cra_name		=	"ctr(aes)",
	.cra_driver_name	=	"ctr-ppc-spe",
	.cra_priority		=	300,
	.cra_flags		=	CRYPTO_ALG_TYPE_BLKCIPHER,
	.cra_blocksize		=	1,
	.cra_ctxsize		=	sizeof(struct ppc_aes_ctx),
	.cra_alignmask		=	0,
	.cra_type		=	&crypto_blkcipher_type,
	.cra_module		=	THIS_MODULE,
	.cra_u = {
		.blkcipher = {
			.min_keysize		=	AES_MIN_KEY_SIZE,
			.max_keysize		=	AES_MAX_KEY_SIZE,
			.ivsize			=	AES_BLOCK_SIZE,
			.setkey			=	ppc_aes_setkey,
			.encrypt		=	ppc_ctr_crypt,
			.decrypt		=	ppc_ctr_crypt,
		}
	}
}, {
	.cra_name		=	"xts(aes)",
	.cra_driver_name	=	"xts-ppc-spe",
	.cra_priority		=	300,
	.cra_flags		=	CRYPTO_ALG_TYPE_BLKCIPHER,
	.cra_blocksize		=	AES_BLOCK_SIZE,
	.cra_ctxsize		=	sizeof(struct ppc_xts_ctx),
	.cra_alignmask		=	0,
	.cra_type		=	&crypto_blkcipher_type,
	.cra_module		=	THIS_MODULE,
	.cra_u = {
		.blkcipher = {
			.min_keysize		=	AES_MIN_KEY_SIZE * 2,
			.max_keysize		=	AES_MAX_KEY_SIZE * 2,
			.ivsize			=	AES_BLOCK_SIZE,
			.setkey			=	ppc_xts_setkey,
			.encrypt		=	ppc_xts_encrypt,
			.decrypt		=	ppc_xts_decrypt,
		}
	}
} };

static int __init ppc_aes_mod_init(void)
{
	return crypto_register_algs(aes_algs, ARRAY_SIZE(aes_algs));
}

static void __exit ppc_aes_mod_fini(void)
{
	crypto_unregister_algs(aes_algs, ARRAY_SIZE(aes_algs));
}

module_init(ppc_aes_mod_init);
module_exit(ppc_aes_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("AES-ECB/CBC/CTR/XTS, SPE optimized");

MODULE_ALIAS_CRYPTO("aes");
MODULE_ALIAS_CRYPTO("ecb(aes)");
MODULE_ALIAS_CRYPTO("cbc(aes)");
MODULE_ALIAS_CRYPTO("ctr(aes)");
MODULE_ALIAS_CRYPTO("xts(aes)");
MODULE_ALIAS_CRYPTO("aes-ppc-spe");
Commit	Line	Data
8a28a1a8 MS	1	/*
	2	* Glue code for AES implementation for SPE instructions (PPC)
	3	*
	4	* Based on generic implementation. The assembler module takes care
	5	* about the SPE registers so it can run from interrupt context.
	6	*
	7	* Copyright (c) 2015 Markus Stockhausen <stockhausen@collogia.de>
	8	*
	9	* This program is free software; you can redistribute it and/or modify it
	10	* under the terms of the GNU General Public License as published by the Free
	11	* Software Foundation; either version 2 of the License, or (at your option)
	12	* any later version.
	13	*
	14	*/
	15
	16	#include <crypto/aes.h>
	17	#include <linux/module.h>
	18	#include <linux/init.h>
	19	#include <linux/types.h>
	20	#include <linux/errno.h>
	21	#include <linux/crypto.h>
	22	#include <asm/byteorder.h>
	23	#include <asm/switch_to.h>
	24	#include <crypto/algapi.h>
	25
	26	/*
	27	* MAX_BYTES defines the number of bytes that are allowed to be processed
	28	* between preempt_disable() and preempt_enable(). e500 cores can issue two
	29	* instructions per clock cycle using one 32/64 bit unit (SU1) and one 32
	30	* bit unit (SU2). One of these can be a memory access that is executed via
	31	* a single load and store unit (LSU). XTS-AES-256 takes ~780 operations per
	32	* 16 byte block block or 25 cycles per byte. Thus 768 bytes of input data
	33	* will need an estimated maximum of 20,000 cycles. Headroom for cache misses
	34	* included. Even with the low end model clocked at 667 MHz this equals to a
	35	* critical time window of less than 30us. The value has been choosen to
	36	* process a 512 byte disk block in one or a large 1400 bytes IPsec network
	37	* packet in two runs.
	38	*
	39	*/
	40	#define MAX_BYTES 768
	41
	42	struct ppc_aes_ctx {
	43	u32 key_enc[AES_MAX_KEYLENGTH_U32];
	44	u32 key_dec[AES_MAX_KEYLENGTH_U32];
	45	u32 rounds;
	46	};
	47
	48	struct ppc_xts_ctx {
	49	u32 key_enc[AES_MAX_KEYLENGTH_U32];
	50	u32 key_dec[AES_MAX_KEYLENGTH_U32];
	51	u32 key_twk[AES_MAX_KEYLENGTH_U32];
	52	u32 rounds;
	53	};
	54
	55	extern void ppc_encrypt_aes(u8 out, const u8 in, u32 *key_enc, u32 rounds);
	56	extern void ppc_decrypt_aes(u8 out, const u8 in, u32 *key_dec, u32 rounds);
	57	extern void ppc_encrypt_ecb(u8 out, const u8 in, u32 *key_enc, u32 rounds,
	58	u32 bytes);
	59	extern void ppc_decrypt_ecb(u8 out, const u8 in, u32 *key_dec, u32 rounds,
	60	u32 bytes);
	61	extern void ppc_encrypt_cbc(u8 out, const u8 in, u32 *key_enc, u32 rounds,
	62	u32 bytes, u8 *iv);
	63	extern void ppc_decrypt_cbc(u8 out, const u8 in, u32 *key_dec, u32 rounds,
	64	u32 bytes, u8 *iv);
65	extern void ppc_crypt_ctr (u8 out, const u8 in, u32 *key_enc, u32 rounds,
66	u32 bytes, u8 *iv);
67	extern void ppc_encrypt_xts(u8 out, const u8 in, u32 *key_enc, u32 rounds,
68	u32 bytes, u8 iv, u32 key_twk);
69	extern void ppc_decrypt_xts(u8 out, const u8 in, u32 *key_dec, u32 rounds,
70	u32 bytes, u8 iv, u32 key_twk);
71
72	extern void ppc_expand_key_128(u32 key_enc, const u8 key);
73	extern void ppc_expand_key_192(u32 key_enc, const u8 key);
74	extern void ppc_expand_key_256(u32 key_enc, const u8 key);
75
76	extern void ppc_generate_decrypt_key(u32 key_dec,u32 key_enc,
77	unsigned int key_len);
78
79	static void spe_begin(void)
80	{
81	/* disable preemption and save users SPE registers if required */
82	preempt_disable();
83	enable_kernel_spe();
84	}
85
86	static void spe_end(void)
87	{
dc4fbba1	88	disable_kernel_spe();
8a28a1a8 MS	89	/* reenable preemption */
	90	preempt_enable();
	91	}
	92
	93	static int ppc_aes_setkey(struct crypto_tfm tfm, const u8 in_key,
	94	unsigned int key_len)
	95	{
	96	struct ppc_aes_ctx *ctx = crypto_tfm_ctx(tfm);
	97
	98	if (key_len != AES_KEYSIZE_128 &&
	99	key_len != AES_KEYSIZE_192 &&
	100	key_len != AES_KEYSIZE_256) {
	101	tfm->crt_flags \|= CRYPTO_TFM_RES_BAD_KEY_LEN;
	102	return -EINVAL;
	103	}
	104
	105	switch (key_len) {
	106	case AES_KEYSIZE_128:
	107	ctx->rounds = 4;
	108	ppc_expand_key_128(ctx->key_enc, in_key);
	109	break;
	110	case AES_KEYSIZE_192:
	111	ctx->rounds = 5;
	112	ppc_expand_key_192(ctx->key_enc, in_key);
	113	break;
	114	case AES_KEYSIZE_256:
	115	ctx->rounds = 6;
	116	ppc_expand_key_256(ctx->key_enc, in_key);
	117	break;
	118	}
	119
	120	ppc_generate_decrypt_key(ctx->key_dec, ctx->key_enc, key_len);
	121
	122	return 0;
	123	}
	124
	125	static int ppc_xts_setkey(struct crypto_tfm tfm, const u8 in_key,
	126	unsigned int key_len)
	127	{
	128	struct ppc_xts_ctx *ctx = crypto_tfm_ctx(tfm);
	129
	130	key_len >>= 1;
	131
	132	if (key_len != AES_KEYSIZE_128 &&
	133	key_len != AES_KEYSIZE_192 &&
	134	key_len != AES_KEYSIZE_256) {
	135	tfm->crt_flags \|= CRYPTO_TFM_RES_BAD_KEY_LEN;
	136	return -EINVAL;
	137	}
	138
	139	switch (key_len) {
	140	case AES_KEYSIZE_128:
	141	ctx->rounds = 4;
	142	ppc_expand_key_128(ctx->key_enc, in_key);
	143	ppc_expand_key_128(ctx->key_twk, in_key + AES_KEYSIZE_128);
	144	break;
	145	case AES_KEYSIZE_192:
	146	ctx->rounds = 5;
	147	ppc_expand_key_192(ctx->key_enc, in_key);
	148	ppc_expand_key_192(ctx->key_twk, in_key + AES_KEYSIZE_192);
	149	break;
	150	case AES_KEYSIZE_256:
	151	ctx->rounds = 6;
	152	ppc_expand_key_256(ctx->key_enc, in_key);
153	ppc_expand_key_256(ctx->key_twk, in_key + AES_KEYSIZE_256);
154	break;
155	}
156
157	ppc_generate_decrypt_key(ctx->key_dec, ctx->key_enc, key_len);
158
159	return 0;
160	}
161
162	static void ppc_aes_encrypt(struct crypto_tfm tfm, u8 out, const u8 *in)
163	{
164	struct ppc_aes_ctx *ctx = crypto_tfm_ctx(tfm);
165
166	spe_begin();
167	ppc_encrypt_aes(out, in, ctx->key_enc, ctx->rounds);
168	spe_end();
169	}
170
171	static void ppc_aes_decrypt(struct crypto_tfm tfm, u8 out, const u8 *in)
172	{
173	struct ppc_aes_ctx *ctx = crypto_tfm_ctx(tfm);
174
175	spe_begin();
176	ppc_decrypt_aes(out, in, ctx->key_dec, ctx->rounds);
177	spe_end();
178	}
179
180	static int ppc_ecb_encrypt(struct blkcipher_desc desc, struct scatterlist dst,
181	struct scatterlist *src, unsigned int nbytes)
182	{
183	struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
184	struct blkcipher_walk walk;
185	unsigned int ubytes;
186	int err;
187
188	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
189	blkcipher_walk_init(&walk, dst, src, nbytes);
190	err = blkcipher_walk_virt(desc, &walk);
191
192	while ((nbytes = walk.nbytes)) {
193	ubytes = nbytes > MAX_BYTES ?
194	nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
195	nbytes -= ubytes;
196
197	spe_begin();
198	ppc_encrypt_ecb(walk.dst.virt.addr, walk.src.virt.addr,
199	ctx->key_enc, ctx->rounds, nbytes);
200	spe_end();
201
202	err = blkcipher_walk_done(desc, &walk, ubytes);
203	}
204
205	return err;
206	}
207
208	static int ppc_ecb_decrypt(struct blkcipher_desc desc, struct scatterlist dst,
209	struct scatterlist *src, unsigned int nbytes)
210	{
211	struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
212	struct blkcipher_walk walk;
213	unsigned int ubytes;
214	int err;
215
216	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
217	blkcipher_walk_init(&walk, dst, src, nbytes);
218	err = blkcipher_walk_virt(desc, &walk);
219
220	while ((nbytes = walk.nbytes)) {
221	ubytes = nbytes > MAX_BYTES ?
222	nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
223	nbytes -= ubytes;
224
225	spe_begin();
226	ppc_decrypt_ecb(walk.dst.virt.addr, walk.src.virt.addr,
227	ctx->key_dec, ctx->rounds, nbytes);
228	spe_end();
229
230	err = blkcipher_walk_done(desc, &walk, ubytes);
231	}
232
233	return err;
234	}
235
236	static int ppc_cbc_encrypt(struct blkcipher_desc desc, struct scatterlist dst,
237	struct scatterlist *src, unsigned int nbytes)
238	{
239	struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
240	struct blkcipher_walk walk;
241	unsigned int ubytes;
242	int err;
243
244	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
245	blkcipher_walk_init(&walk, dst, src, nbytes);
246	err = blkcipher_walk_virt(desc, &walk);
247
248	while ((nbytes = walk.nbytes)) {
249	ubytes = nbytes > MAX_BYTES ?
250	nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
251	nbytes -= ubytes;
252
253	spe_begin();
254	ppc_encrypt_cbc(walk.dst.virt.addr, walk.src.virt.addr,
255	ctx->key_enc, ctx->rounds, nbytes, walk.iv);
256	spe_end();
257
258	err = blkcipher_walk_done(desc, &walk, ubytes);
259	}
260
261	return err;
262	}
263
264	static int ppc_cbc_decrypt(struct blkcipher_desc desc, struct scatterlist dst,
265	struct scatterlist *src, unsigned int nbytes)
266	{
267	struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
268	struct blkcipher_walk walk;
269	unsigned int ubytes;
270	int err;
271
272	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
273	blkcipher_walk_init(&walk, dst, src, nbytes);
274	err = blkcipher_walk_virt(desc, &walk);
275
276	while ((nbytes = walk.nbytes)) {
277	ubytes = nbytes > MAX_BYTES ?
278	nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
279	nbytes -= ubytes;
280
281	spe_begin();
282	ppc_decrypt_cbc(walk.dst.virt.addr, walk.src.virt.addr,
283	ctx->key_dec, ctx->rounds, nbytes, walk.iv);
284	spe_end();
285
286	err = blkcipher_walk_done(desc, &walk, ubytes);
287	}
288
289	return err;
290	}
291
292	static int ppc_ctr_crypt(struct blkcipher_desc desc, struct scatterlist dst,
293	struct scatterlist *src, unsigned int nbytes)
294	{
295	struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
296	struct blkcipher_walk walk;
297	unsigned int pbytes, ubytes;
298	int err;
299
300	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
301	blkcipher_walk_init(&walk, dst, src, nbytes);
302	err = blkcipher_walk_virt_block(desc, &walk, AES_BLOCK_SIZE);
303
304	while ((pbytes = walk.nbytes)) {
305	pbytes = pbytes > MAX_BYTES ? MAX_BYTES : pbytes;
306	pbytes = pbytes == nbytes ?
307	nbytes : pbytes & ~(AES_BLOCK_SIZE - 1);
308	ubytes = walk.nbytes - pbytes;
309
310	spe_begin();
311	ppc_crypt_ctr(walk.dst.virt.addr, walk.src.virt.addr,
312	ctx->key_enc, ctx->rounds, pbytes , walk.iv);
313	spe_end();
314
315	nbytes -= pbytes;
316	err = blkcipher_walk_done(desc, &walk, ubytes);
317	}
318
319	return err;
320	}
321
322	static int ppc_xts_encrypt(struct blkcipher_desc desc, struct scatterlist dst,
323	struct scatterlist *src, unsigned int nbytes)
324	{
325	struct ppc_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
326	struct blkcipher_walk walk;
327	unsigned int ubytes;
328	int err;
329	u32 *twk;
330
331	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
332	blkcipher_walk_init(&walk, dst, src, nbytes);
333	err = blkcipher_walk_virt(desc, &walk);
334	twk = ctx->key_twk;
335
336	while ((nbytes = walk.nbytes)) {
337	ubytes = nbytes > MAX_BYTES ?
338	nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
339	nbytes -= ubytes;
340
341	spe_begin();
342	ppc_encrypt_xts(walk.dst.virt.addr, walk.src.virt.addr,
343	ctx->key_enc, ctx->rounds, nbytes, walk.iv, twk);
344	spe_end();
345
346	twk = NULL;
347	err = blkcipher_walk_done(desc, &walk, ubytes);
348	}
349
350	return err;
351	}
352
353	static int ppc_xts_decrypt(struct blkcipher_desc desc, struct scatterlist dst,
354	struct scatterlist *src, unsigned int nbytes)
355	{
356	struct ppc_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
357	struct blkcipher_walk walk;
358	unsigned int ubytes;
359	int err;
360	u32 *twk;
361
362	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
363	blkcipher_walk_init(&walk, dst, src, nbytes);
364	err = blkcipher_walk_virt(desc, &walk);
365	twk = ctx->key_twk;
366
367	while ((nbytes = walk.nbytes)) {
368	ubytes = nbytes > MAX_BYTES ?
369	nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
370	nbytes -= ubytes;
371
372	spe_begin();
373	ppc_decrypt_xts(walk.dst.virt.addr, walk.src.virt.addr,
374	ctx->key_dec, ctx->rounds, nbytes, walk.iv, twk);
375	spe_end();
376
377	twk = NULL;
378	err = blkcipher_walk_done(desc, &walk, ubytes);
379	}
380
381	return err;
382	}
383
384	/*
385	* Algorithm definitions. Disabling alignment (cra_alignmask=0) was chosen
386	* because the e500 platform can handle unaligned reads/writes very efficently.
387	* This improves IPsec thoughput by another few percent. Additionally we assume
388	* that AES context is always aligned to at least 8 bytes because it is created
389	* with kmalloc() in the crypto infrastructure
390	*
391	*/
392	static struct crypto_alg aes_algs[] = { {
393	.cra_name = "aes",
394	.cra_driver_name = "aes-ppc-spe",
395	.cra_priority = 300,
396	.cra_flags = CRYPTO_ALG_TYPE_CIPHER,
397	.cra_blocksize = AES_BLOCK_SIZE,
398	.cra_ctxsize = sizeof(struct ppc_aes_ctx),
399	.cra_alignmask = 0,
400	.cra_module = THIS_MODULE,
401	.cra_u = {
402	.cipher = {
403	.cia_min_keysize = AES_MIN_KEY_SIZE,
404	.cia_max_keysize = AES_MAX_KEY_SIZE,
405	.cia_setkey = ppc_aes_setkey,
406	.cia_encrypt = ppc_aes_encrypt,
407	.cia_decrypt = ppc_aes_decrypt
408	}
409	}
410	}, {
411	.cra_name = "ecb(aes)",
412	.cra_driver_name = "ecb-ppc-spe",
413	.cra_priority = 300,
414	.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
415	.cra_blocksize = AES_BLOCK_SIZE,
416	.cra_ctxsize = sizeof(struct ppc_aes_ctx),
417	.cra_alignmask = 0,
418	.cra_type = &crypto_blkcipher_type,
419	.cra_module = THIS_MODULE,
420	.cra_u = {
421	.blkcipher = {
422	.min_keysize = AES_MIN_KEY_SIZE,
423	.max_keysize = AES_MAX_KEY_SIZE,
424	.ivsize = AES_BLOCK_SIZE,
425	.setkey = ppc_aes_setkey,
426	.encrypt = ppc_ecb_encrypt,
427	.decrypt = ppc_ecb_decrypt,
428	}
429	}
430	}, {
431	.cra_name = "cbc(aes)",
432	.cra_driver_name = "cbc-ppc-spe",
433	.cra_priority = 300,
434	.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
435	.cra_blocksize = AES_BLOCK_SIZE,
436	.cra_ctxsize = sizeof(struct ppc_aes_ctx),
437	.cra_alignmask = 0,
438	.cra_type = &crypto_blkcipher_type,
439	.cra_module = THIS_MODULE,
440	.cra_u = {
441	.blkcipher = {
442	.min_keysize = AES_MIN_KEY_SIZE,
443	.max_keysize = AES_MAX_KEY_SIZE,
444	.ivsize = AES_BLOCK_SIZE,
445	.setkey = ppc_aes_setkey,
446	.encrypt = ppc_cbc_encrypt,
447	.decrypt = ppc_cbc_decrypt,
448	}
449	}
450	}, {
451	.cra_name = "ctr(aes)",
452	.cra_driver_name = "ctr-ppc-spe",
453	.cra_priority = 300,
454	.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
455	.cra_blocksize = 1,
456	.cra_ctxsize = sizeof(struct ppc_aes_ctx),
457	.cra_alignmask = 0,
458	.cra_type = &crypto_blkcipher_type,
459	.cra_module = THIS_MODULE,
460	.cra_u = {
461	.blkcipher = {
462	.min_keysize = AES_MIN_KEY_SIZE,
463	.max_keysize = AES_MAX_KEY_SIZE,
464	.ivsize = AES_BLOCK_SIZE,
465	.setkey = ppc_aes_setkey,
466	.encrypt = ppc_ctr_crypt,
467	.decrypt = ppc_ctr_crypt,
468	}
469	}
470	}, {
471	.cra_name = "xts(aes)",
472	.cra_driver_name = "xts-ppc-spe",
473	.cra_priority = 300,
474	.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
475	.cra_blocksize = AES_BLOCK_SIZE,
476	.cra_ctxsize = sizeof(struct ppc_xts_ctx),
477	.cra_alignmask = 0,
478	.cra_type = &crypto_blkcipher_type,
479	.cra_module = THIS_MODULE,
480	.cra_u = {
481	.blkcipher = {
482	.min_keysize = AES_MIN_KEY_SIZE * 2,
483	.max_keysize = AES_MAX_KEY_SIZE * 2,
484	.ivsize = AES_BLOCK_SIZE,
485	.setkey = ppc_xts_setkey,
486	.encrypt = ppc_xts_encrypt,
487	.decrypt = ppc_xts_decrypt,
488	}
489	}
490	} };
491
492	static int __init ppc_aes_mod_init(void)
493	{
494	return crypto_register_algs(aes_algs, ARRAY_SIZE(aes_algs));
495	}
496
497	static void __exit ppc_aes_mod_fini(void)
498	{
499	crypto_unregister_algs(aes_algs, ARRAY_SIZE(aes_algs));
500	}
501
502	module_init(ppc_aes_mod_init);
503	module_exit(ppc_aes_mod_fini);
504
505	MODULE_LICENSE("GPL");
506	MODULE_DESCRIPTION("AES-ECB/CBC/CTR/XTS, SPE optimized");
507
508	MODULE_ALIAS_CRYPTO("aes");
509	MODULE_ALIAS_CRYPTO("ecb(aes)");
510	MODULE_ALIAS_CRYPTO("cbc(aes)");
511	MODULE_ALIAS_CRYPTO("ctr(aes)");
512	MODULE_ALIAS_CRYPTO("xts(aes)");
513	MODULE_ALIAS_CRYPTO("aes-ppc-spe");