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Commit e81792fb authored by Jussi Kivilinna's avatar Jussi Kivilinna Committed by Herbert Xu
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crypto: serpent-sse2 - prepare serpent-sse2 glue code into generic x86 glue...


crypto: serpent-sse2 - prepare serpent-sse2 glue code into generic x86 glue code for 128bit block ciphers

Block cipher implementations in arch/x86/crypto/ contain common glue code that
is currently duplicated in each module (camellia-x86_64, twofish-x86_64-3way,
twofish-avx, serpent-sse2 and serpent-avx). This patch prepares serpent-sse2
glue into generic glue code for all 128bit block ciphers to use in
arch/x86/crypto.

Signed-off-by: default avatarJussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent a9629d71
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+303 −163
Original line number Diff line number Diff line
@@ -48,105 +48,129 @@
#include <linux/workqueue.h>
#include <linux/spinlock.h>

static inline bool serpent_fpu_begin(bool fpu_enabled, unsigned int nbytes)
typedef void (*common_glue_func_t)(void *ctx, u8 *dst, const u8 *src);
typedef void (*common_glue_cbc_func_t)(void *ctx, u128 *dst, const u128 *src);
typedef void (*common_glue_ctr_func_t)(void *ctx, u128 *dst, const u128 *src,
				       u128 *iv);

#define GLUE_FUNC_CAST(fn) ((common_glue_func_t)(fn))
#define GLUE_CBC_FUNC_CAST(fn) ((common_glue_cbc_func_t)(fn))
#define GLUE_CTR_FUNC_CAST(fn) ((common_glue_ctr_func_t)(fn))

struct common_glue_func_entry {
	unsigned int num_blocks; /* number of blocks that @fn will process */
	union {
		common_glue_func_t ecb;
		common_glue_cbc_func_t cbc;
		common_glue_ctr_func_t ctr;
	} fn_u;
};

struct common_glue_ctx {
	unsigned int num_funcs;
	int fpu_blocks_limit; /* -1 means fpu not needed at all */

	/*
	 * First funcs entry must have largest num_blocks and last funcs entry
	 * must have num_blocks == 1!
	 */
	struct common_glue_func_entry funcs[];
};

static inline bool glue_fpu_begin(unsigned int bsize, int fpu_blocks_limit,
				  struct blkcipher_desc *desc,
				  bool fpu_enabled, unsigned int nbytes)
{
	if (likely(fpu_blocks_limit < 0))
		return false;

	if (fpu_enabled)
		return true;

	/* SSE2 is only used when chunk to be processed is large enough, so
	 * do not enable FPU until it is necessary.
	/*
	 * Vector-registers are only used when chunk to be processed is large
	 * enough, so do not enable FPU until it is necessary.
	 */
	if (nbytes < SERPENT_BLOCK_SIZE * SERPENT_PARALLEL_BLOCKS)
	if (nbytes < bsize * (unsigned int)fpu_blocks_limit)
		return false;

	if (desc) {
		/* prevent sleeping if FPU is in use */
		desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
	}

	kernel_fpu_begin();
	return true;
}

static inline void serpent_fpu_end(bool fpu_enabled)
static inline void glue_fpu_end(bool fpu_enabled)
{
	if (fpu_enabled)
		kernel_fpu_end();
}

static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk,
		     bool enc)
static int __glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx,
				   struct blkcipher_desc *desc,
				   struct blkcipher_walk *walk)
{
	void *ctx = crypto_blkcipher_ctx(desc->tfm);
	const unsigned int bsize = 128 / 8;
	unsigned int nbytes, i, func_bytes;
	bool fpu_enabled = false;
	struct serpent_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	const unsigned int bsize = SERPENT_BLOCK_SIZE;
	unsigned int nbytes;
	int err;

	err = blkcipher_walk_virt(desc, walk);
	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;

	while ((nbytes = walk->nbytes)) {
		u8 *wsrc = walk->src.virt.addr;
		u8 *wdst = walk->dst.virt.addr;

		fpu_enabled = serpent_fpu_begin(fpu_enabled, nbytes);
		fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
					     desc, fpu_enabled, nbytes);

		for (i = 0; i < gctx->num_funcs; i++) {
			func_bytes = bsize * gctx->funcs[i].num_blocks;

			/* Process multi-block batch */
		if (nbytes >= bsize * SERPENT_PARALLEL_BLOCKS) {
			if (nbytes >= func_bytes) {
				do {
				if (enc)
					serpent_enc_blk_xway(ctx, wdst, wsrc);
				else
					serpent_dec_blk_xway(ctx, wdst, wsrc);
					gctx->funcs[i].fn_u.ecb(ctx, wdst,
								wsrc);

				wsrc += bsize * SERPENT_PARALLEL_BLOCKS;
				wdst += bsize * SERPENT_PARALLEL_BLOCKS;
				nbytes -= bsize * SERPENT_PARALLEL_BLOCKS;
			} while (nbytes >= bsize * SERPENT_PARALLEL_BLOCKS);
					wsrc += func_bytes;
					wdst += func_bytes;
					nbytes -= func_bytes;
				} while (nbytes >= func_bytes);

				if (nbytes < bsize)
					goto done;
			}

		/* Handle leftovers */
		do {
			if (enc)
				__serpent_encrypt(ctx, wdst, wsrc);
			else
				__serpent_decrypt(ctx, wdst, wsrc);

			wsrc += bsize;
			wdst += bsize;
			nbytes -= bsize;
		} while (nbytes >= bsize);
		}

done:
		err = blkcipher_walk_done(desc, walk, nbytes);
	}

	serpent_fpu_end(fpu_enabled);
	glue_fpu_end(fpu_enabled);
	return err;
}

static int ecb_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
int glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx,
			  struct blkcipher_desc *desc, struct scatterlist *dst,
			  struct scatterlist *src, unsigned int nbytes)
{
	struct blkcipher_walk walk;

	blkcipher_walk_init(&walk, dst, src, nbytes);
	return ecb_crypt(desc, &walk, true);
	return __glue_ecb_crypt_128bit(gctx, desc, &walk);
}

static int ecb_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
		       struct scatterlist *src, unsigned int nbytes)
{
	struct blkcipher_walk walk;

	blkcipher_walk_init(&walk, dst, src, nbytes);
	return ecb_crypt(desc, &walk, false);
}

static unsigned int __cbc_encrypt(struct blkcipher_desc *desc,
static unsigned int __glue_cbc_encrypt_128bit(const common_glue_func_t fn,
					      struct blkcipher_desc *desc,
					      struct blkcipher_walk *walk)
{
	struct serpent_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	const unsigned int bsize = SERPENT_BLOCK_SIZE;
	void *ctx = crypto_blkcipher_ctx(desc->tfm);
	const unsigned int bsize = 128 / 8;
	unsigned int nbytes = walk->nbytes;
	u128 *src = (u128 *)walk->src.virt.addr;
	u128 *dst = (u128 *)walk->dst.virt.addr;
@@ -154,7 +178,7 @@ static unsigned int __cbc_encrypt(struct blkcipher_desc *desc,

	do {
		u128_xor(dst, src, iv);
		__serpent_encrypt(ctx, (u8 *)dst, (u8 *)dst);
		fn(ctx, (u8 *)dst, (u8 *)dst);
		iv = dst;

		src += 1;
@@ -166,7 +190,9 @@ static unsigned int __cbc_encrypt(struct blkcipher_desc *desc,
	return nbytes;
}

static int cbc_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
int glue_cbc_encrypt_128bit(const common_glue_func_t fn,
			    struct blkcipher_desc *desc,
			    struct scatterlist *dst,
			    struct scatterlist *src, unsigned int nbytes)
{
	struct blkcipher_walk walk;
@@ -176,24 +202,26 @@ static int cbc_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
	err = blkcipher_walk_virt(desc, &walk);

	while ((nbytes = walk.nbytes)) {
		nbytes = __cbc_encrypt(desc, &walk);
		nbytes = __glue_cbc_encrypt_128bit(fn, desc, &walk);
		err = blkcipher_walk_done(desc, &walk, nbytes);
	}

	return err;
}

static unsigned int __cbc_decrypt(struct blkcipher_desc *desc,
static unsigned int
__glue_cbc_decrypt_128bit(const struct common_glue_ctx *gctx,
			  struct blkcipher_desc *desc,
			  struct blkcipher_walk *walk)
{
	struct serpent_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	const unsigned int bsize = SERPENT_BLOCK_SIZE;
	void *ctx = crypto_blkcipher_ctx(desc->tfm);
	const unsigned int bsize = 128 / 8;
	unsigned int nbytes = walk->nbytes;
	u128 *src = (u128 *)walk->src.virt.addr;
	u128 *dst = (u128 *)walk->dst.virt.addr;
	u128 ivs[SERPENT_PARALLEL_BLOCKS - 1];
	u128 last_iv;
	int i;
	unsigned int num_blocks, func_bytes;
	unsigned int i;

	/* Start of the last block. */
	src += nbytes / bsize - 1;
@@ -201,20 +229,18 @@ static unsigned int __cbc_decrypt(struct blkcipher_desc *desc,

	last_iv = *src;

	for (i = 0; i < gctx->num_funcs; i++) {
		num_blocks = gctx->funcs[i].num_blocks;
		func_bytes = bsize * num_blocks;

		/* Process multi-block batch */
	if (nbytes >= bsize * SERPENT_PARALLEL_BLOCKS) {
		if (nbytes >= func_bytes) {
			do {
			nbytes -= bsize * (SERPENT_PARALLEL_BLOCKS - 1);
			src -= SERPENT_PARALLEL_BLOCKS - 1;
			dst -= SERPENT_PARALLEL_BLOCKS - 1;

			for (i = 0; i < SERPENT_PARALLEL_BLOCKS - 1; i++)
				ivs[i] = src[i];

			serpent_dec_blk_xway(ctx, (u8 *)dst, (u8 *)src);
				nbytes -= func_bytes - bsize;
				src -= num_blocks - 1;
				dst -= num_blocks - 1;

			for (i = 0; i < SERPENT_PARALLEL_BLOCKS - 1; i++)
				u128_xor(dst + (i + 1), dst + (i + 1), ivs + i);
				gctx->funcs[i].fn_u.cbc(ctx, dst, src);

				nbytes -= bsize;
				if (nbytes < bsize)
@@ -223,23 +249,11 @@ static unsigned int __cbc_decrypt(struct blkcipher_desc *desc,
				u128_xor(dst, dst, src - 1);
				src -= 1;
				dst -= 1;
		} while (nbytes >= bsize * SERPENT_PARALLEL_BLOCKS);
			} while (nbytes >= func_bytes);

			if (nbytes < bsize)
				goto done;
		}

	/* Handle leftovers */
	for (;;) {
		__serpent_decrypt(ctx, (u8 *)dst, (u8 *)src);

		nbytes -= bsize;
		if (nbytes < bsize)
			break;

		u128_xor(dst, dst, src - 1);
		src -= 1;
		dst -= 1;
	}

done:
@@ -249,24 +263,27 @@ static unsigned int __cbc_decrypt(struct blkcipher_desc *desc,
	return nbytes;
}

static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
int glue_cbc_decrypt_128bit(const struct common_glue_ctx *gctx,
			    struct blkcipher_desc *desc,
			    struct scatterlist *dst,
			    struct scatterlist *src, unsigned int nbytes)
{
	const unsigned int bsize = 128 / 8;
	bool fpu_enabled = false;
	struct blkcipher_walk walk;
	int err;

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

	while ((nbytes = walk.nbytes)) {
		fpu_enabled = serpent_fpu_begin(fpu_enabled, nbytes);
		nbytes = __cbc_decrypt(desc, &walk);
		fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
					     desc, fpu_enabled, nbytes);
		nbytes = __glue_cbc_decrypt_128bit(gctx, desc, &walk);
		err = blkcipher_walk_done(desc, &walk, nbytes);
	}

	serpent_fpu_end(fpu_enabled);
	glue_fpu_end(fpu_enabled);
	return err;
}

@@ -289,109 +306,232 @@ static inline void u128_inc(u128 *i)
		i->a++;
}

static void ctr_crypt_final(struct blkcipher_desc *desc,
static void glue_ctr_crypt_final_128bit(const common_glue_ctr_func_t fn_ctr,
					struct blkcipher_desc *desc,
					struct blkcipher_walk *walk)
{
	struct serpent_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	u8 *ctrblk = walk->iv;
	u8 keystream[SERPENT_BLOCK_SIZE];
	u8 *src = walk->src.virt.addr;
	u8 *dst = walk->dst.virt.addr;
	void *ctx = crypto_blkcipher_ctx(desc->tfm);
	u8 *src = (u8 *)walk->src.virt.addr;
	u8 *dst = (u8 *)walk->dst.virt.addr;
	unsigned int nbytes = walk->nbytes;
	u128 ctrblk;
	u128 tmp;

	be128_to_u128(&ctrblk, (be128 *)walk->iv);

	__serpent_encrypt(ctx, keystream, ctrblk);
	crypto_xor(keystream, src, nbytes);
	memcpy(dst, keystream, nbytes);
	memcpy(&tmp, src, nbytes);
	fn_ctr(ctx, &tmp, &tmp, &ctrblk);
	memcpy(dst, &tmp, nbytes);

	crypto_inc(ctrblk, SERPENT_BLOCK_SIZE);
	u128_to_be128((be128 *)walk->iv, &ctrblk);
}

static unsigned int __ctr_crypt(struct blkcipher_desc *desc,
static unsigned int __glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx,
					    struct blkcipher_desc *desc,
					    struct blkcipher_walk *walk)
{
	struct serpent_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	const unsigned int bsize = SERPENT_BLOCK_SIZE;
	const unsigned int bsize = 128 / 8;
	void *ctx = crypto_blkcipher_ctx(desc->tfm);
	unsigned int nbytes = walk->nbytes;
	u128 *src = (u128 *)walk->src.virt.addr;
	u128 *dst = (u128 *)walk->dst.virt.addr;
	u128 ctrblk;
	be128 ctrblocks[SERPENT_PARALLEL_BLOCKS];
	int i;
	unsigned int num_blocks, func_bytes;
	unsigned int i;

	be128_to_u128(&ctrblk, (be128 *)walk->iv);

	/* Process multi-block batch */
	if (nbytes >= bsize * SERPENT_PARALLEL_BLOCKS) {
		do {
			/* create ctrblks for parallel encrypt */
			for (i = 0; i < SERPENT_PARALLEL_BLOCKS; i++) {
				if (dst != src)
					dst[i] = src[i];

				u128_to_be128(&ctrblocks[i], &ctrblk);
				u128_inc(&ctrblk);
			}
	for (i = 0; i < gctx->num_funcs; i++) {
		num_blocks = gctx->funcs[i].num_blocks;
		func_bytes = bsize * num_blocks;

			serpent_enc_blk_xway_xor(ctx, (u8 *)dst,
						 (u8 *)ctrblocks);
		if (nbytes >= func_bytes) {
			do {
				gctx->funcs[i].fn_u.ctr(ctx, dst, src, &ctrblk);

			src += SERPENT_PARALLEL_BLOCKS;
			dst += SERPENT_PARALLEL_BLOCKS;
			nbytes -= bsize * SERPENT_PARALLEL_BLOCKS;
		} while (nbytes >= bsize * SERPENT_PARALLEL_BLOCKS);
				src += num_blocks;
				dst += num_blocks;
				nbytes -= func_bytes;
			} while (nbytes >= func_bytes);

			if (nbytes < bsize)
				goto done;
		}

	/* Handle leftovers */
	do {
		if (dst != src)
			*dst = *src;

		u128_to_be128(&ctrblocks[0], &ctrblk);
		u128_inc(&ctrblk);

		__serpent_encrypt(ctx, (u8 *)ctrblocks, (u8 *)ctrblocks);
		u128_xor(dst, dst, (u128 *)ctrblocks);

		src += 1;
		dst += 1;
		nbytes -= bsize;
	} while (nbytes >= bsize);
	}

done:
	u128_to_be128((be128 *)walk->iv, &ctrblk);
	return nbytes;
}

static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
int glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx,
			  struct blkcipher_desc *desc, struct scatterlist *dst,
			  struct scatterlist *src, unsigned int nbytes)
{
	const unsigned int bsize = 128 / 8;
	bool fpu_enabled = false;
	struct blkcipher_walk walk;
	int err;

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

	while ((nbytes = walk.nbytes) >= SERPENT_BLOCK_SIZE) {
		fpu_enabled = serpent_fpu_begin(fpu_enabled, nbytes);
		nbytes = __ctr_crypt(desc, &walk);
	while ((nbytes = walk.nbytes) >= bsize) {
		fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
					     desc, fpu_enabled, nbytes);
		nbytes = __glue_ctr_crypt_128bit(gctx, desc, &walk);
		err = blkcipher_walk_done(desc, &walk, nbytes);
	}

	serpent_fpu_end(fpu_enabled);
	glue_fpu_end(fpu_enabled);

	if (walk.nbytes) {
		ctr_crypt_final(desc, &walk);
		glue_ctr_crypt_final_128bit(
			gctx->funcs[gctx->num_funcs - 1].fn_u.ctr, desc, &walk);
		err = blkcipher_walk_done(desc, &walk, 0);
	}

	return err;
}

static void serpent_decrypt_cbc_xway(void *ctx, u128 *dst, const u128 *src)
{
	u128 ivs[SERPENT_PARALLEL_BLOCKS - 1];
	unsigned int j;

	for (j = 0; j < SERPENT_PARALLEL_BLOCKS - 1; j++)
		ivs[j] = src[j];

	serpent_dec_blk_xway(ctx, (u8 *)dst, (u8 *)src);

	for (j = 0; j < SERPENT_PARALLEL_BLOCKS - 1; j++)
		u128_xor(dst + (j + 1), dst + (j + 1), ivs + j);
}

static void serpent_crypt_ctr(void *ctx, u128 *dst, const u128 *src, u128 *iv)
{
	be128 ctrblk;

	u128_to_be128(&ctrblk, iv);
	u128_inc(iv);

	__serpent_encrypt(ctx, (u8 *)&ctrblk, (u8 *)&ctrblk);
	u128_xor(dst, src, (u128 *)&ctrblk);
}

static void serpent_crypt_ctr_xway(void *ctx, u128 *dst, const u128 *src,
				   u128 *iv)
{
	be128 ctrblks[SERPENT_PARALLEL_BLOCKS];
	unsigned int i;

	for (i = 0; i < SERPENT_PARALLEL_BLOCKS; i++) {
		if (dst != src)
			dst[i] = src[i];

		u128_to_be128(&ctrblks[i], iv);
		u128_inc(iv);
	}

	serpent_enc_blk_xway_xor(ctx, (u8 *)dst, (u8 *)ctrblks);
}

static const struct common_glue_ctx serpent_enc = {
	.num_funcs = 2,
	.fpu_blocks_limit = SERPENT_PARALLEL_BLOCKS,

	.funcs = { {
		.num_blocks = SERPENT_PARALLEL_BLOCKS,
		.fn_u = { .ecb = GLUE_FUNC_CAST(serpent_enc_blk_xway) }
	}, {
		.num_blocks = 1,
		.fn_u = { .ecb = GLUE_FUNC_CAST(__serpent_encrypt) }
	} }
};

static const struct common_glue_ctx serpent_ctr = {
	.num_funcs = 2,
	.fpu_blocks_limit = SERPENT_PARALLEL_BLOCKS,

	.funcs = { {
		.num_blocks = SERPENT_PARALLEL_BLOCKS,
		.fn_u = { .ctr = GLUE_CTR_FUNC_CAST(serpent_crypt_ctr_xway) }
	}, {
		.num_blocks = 1,
		.fn_u = { .ctr = GLUE_CTR_FUNC_CAST(serpent_crypt_ctr) }
	} }
};

static const struct common_glue_ctx serpent_dec = {
	.num_funcs = 2,
	.fpu_blocks_limit = SERPENT_PARALLEL_BLOCKS,

	.funcs = { {
		.num_blocks = SERPENT_PARALLEL_BLOCKS,
		.fn_u = { .ecb = GLUE_FUNC_CAST(serpent_dec_blk_xway) }
	}, {
		.num_blocks = 1,
		.fn_u = { .ecb = GLUE_FUNC_CAST(__serpent_decrypt) }
	} }
};

static const struct common_glue_ctx serpent_dec_cbc = {
	.num_funcs = 2,
	.fpu_blocks_limit = SERPENT_PARALLEL_BLOCKS,

	.funcs = { {
		.num_blocks = SERPENT_PARALLEL_BLOCKS,
		.fn_u = { .cbc = GLUE_CBC_FUNC_CAST(serpent_decrypt_cbc_xway) }
	}, {
		.num_blocks = 1,
		.fn_u = { .cbc = GLUE_CBC_FUNC_CAST(__serpent_decrypt) }
	} }
};

static int ecb_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
		       struct scatterlist *src, unsigned int nbytes)
{
	return glue_ecb_crypt_128bit(&serpent_enc, desc, dst, src, nbytes);
}

static int ecb_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
		       struct scatterlist *src, unsigned int nbytes)
{
	return glue_ecb_crypt_128bit(&serpent_dec, desc, dst, src, nbytes);
}

static int cbc_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
		       struct scatterlist *src, unsigned int nbytes)
{
	return glue_cbc_encrypt_128bit(GLUE_FUNC_CAST(__serpent_encrypt), desc,
				     dst, src, nbytes);
}

static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
		       struct scatterlist *src, unsigned int nbytes)
{
	return glue_cbc_decrypt_128bit(&serpent_dec_cbc, desc, dst, src,
				       nbytes);
}

static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
		     struct scatterlist *src, unsigned int nbytes)
{
	return glue_ctr_crypt_128bit(&serpent_ctr, desc, dst, src, nbytes);
}

static inline bool serpent_fpu_begin(bool fpu_enabled, unsigned int nbytes)
{
	return glue_fpu_begin(SERPENT_BLOCK_SIZE, SERPENT_PARALLEL_BLOCKS,
			      NULL, fpu_enabled, nbytes);
}

static inline void serpent_fpu_end(bool fpu_enabled)
{
	glue_fpu_end(fpu_enabled);
}

struct crypt_priv {
	struct serpent_ctx *ctx;
	bool fpu_enabled;