[v6,2/2] crypto: Multikey template for essiv

Message ID 1498106510-19793-3-git-send-email-binoy.jayan@linaro.org
State New
Headers show
Series
  • Untitled series #2551
Related show

Commit Message

Binoy Jayan June 22, 2017, 4:41 a.m.
Just for reference and to get the performance numbers.
Not for merging.

Depends on the following patches by Gilad:
 MAINTAINERS: add Gilad BY as maintainer for ccree
 staging: ccree: add devicetree bindings
 staging: ccree: add TODO list
 staging: add ccree crypto driver

A multi key template implementation which calls the underlying
iv generator 'essiv-aes-du512-dx' cum crypto algorithm. This
template sits on top of the underlying IV generator and accepts
a key length that is a multiple of the underlying key length.
This has not been tested on Juno with the CryptoCell accelerator
for which it was written for.

The underlying IV generator 'essiv-aes-du512-dx' generates IV for
every 512 byte blocks.

Signed-off-by: Binoy Jayan <binoy.jayan@linaro.org>

---
 drivers/md/dm-crypt.c            |    5 +-
 drivers/staging/ccree/Makefile   |    2 +-
 drivers/staging/ccree/essiv.c    |  777 ++++++++++++++++++++++++++++
 drivers/staging/ccree/essiv_sw.c | 1040 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 1821 insertions(+), 3 deletions(-)
 create mode 100644 drivers/staging/ccree/essiv.c
 create mode 100644 drivers/staging/ccree/essiv_sw.c

-- 
Binoy Jayan

Patch

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index bef54f5..32f75dd 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -1555,7 +1555,8 @@  static int __init geniv_register_algs(void)
 	if (err)
 		goto out_undo_plain;
 
-	err = crypto_register_template(&crypto_essiv_tmpl);
+	err = 0;
+	// err = crypto_register_template(&crypto_essiv_tmpl);
 	if (err)
 		goto out_undo_plain64;
 
@@ -1594,7 +1595,7 @@  static void __exit geniv_deregister_algs(void)
 {
 	crypto_unregister_template(&crypto_plain_tmpl);
 	crypto_unregister_template(&crypto_plain64_tmpl);
-	crypto_unregister_template(&crypto_essiv_tmpl);
+	// crypto_unregister_template(&crypto_essiv_tmpl);
 	crypto_unregister_template(&crypto_benbi_tmpl);
 	crypto_unregister_template(&crypto_null_tmpl);
 	crypto_unregister_template(&crypto_lmk_tmpl);
diff --git a/drivers/staging/ccree/Makefile b/drivers/staging/ccree/Makefile
index 44f3e3e..524e930 100644
--- a/drivers/staging/ccree/Makefile
+++ b/drivers/staging/ccree/Makefile
@@ -1,3 +1,3 @@ 
 obj-$(CONFIG_CRYPTO_DEV_CCREE) := ccree.o
-ccree-y := ssi_driver.o ssi_sysfs.o ssi_buffer_mgr.o ssi_request_mgr.o ssi_cipher.o ssi_hash.o ssi_aead.o ssi_ivgen.o ssi_sram_mgr.o ssi_pm.o ssi_pm_ext.o
+ccree-y := ssi_driver.o ssi_sysfs.o ssi_buffer_mgr.o ssi_request_mgr.o ssi_cipher.o ssi_hash.o ssi_aead.o ssi_ivgen.o ssi_sram_mgr.o ssi_pm.o ssi_pm_ext.o essiv.o
 ccree-$(CCREE_FIPS_SUPPORT) += ssi_fips.o ssi_fips_ll.o ssi_fips_ext.o ssi_fips_local.o
diff --git a/drivers/staging/ccree/essiv.c b/drivers/staging/ccree/essiv.c
new file mode 100644
index 0000000..719b8bf
--- /dev/null
+++ b/drivers/staging/ccree/essiv.c
@@ -0,0 +1,777 @@ 
+/*
+ * Copyright (C) 2003 Jana Saout <jana@saout.de>
+ * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org>
+ * Copyright (C) 2006-2015 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2013 Milan Broz <gmazyland@gmail.com>
+ *
+ * This file is released under the GPL.
+ */
+
+#include <linux/completion.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/key.h>
+#include <linux/bio.h>
+#include <linux/blkdev.h>
+#include <linux/mempool.h>
+#include <linux/slab.h>
+#include <linux/crypto.h>
+#include <linux/workqueue.h>
+#include <linux/kthread.h>
+#include <linux/backing-dev.h>
+#include <linux/atomic.h>
+#include <linux/scatterlist.h>
+#include <linux/rbtree.h>
+#include <linux/ctype.h>
+#include <asm/page.h>
+#include <asm/unaligned.h>
+#include <crypto/hash.h>
+#include <crypto/md5.h>
+#include <crypto/algapi.h>
+#include <crypto/skcipher.h>
+#include <keys/user-type.h>
+#include <linux/device-mapper.h>
+#include <crypto/internal/skcipher.h>
+#include <linux/backing-dev.h>
+#include <linux/log2.h>
+#include <crypto/geniv.h>
+
+#define DM_MSG_PREFIX		"crypt"
+#define MAX_SG_LIST		(BIO_MAX_PAGES * 8)
+#define MIN_IOS			64
+#define LMK_SEED_SIZE		64 /* hash + 0 */
+#define TCW_WHITENING_SIZE	16
+
+struct geniv_ctx;
+struct geniv_req_ctx;
+
+/* Sub request for each of the skcipher_request's for a segment */
+struct geniv_subreq {
+	struct scatterlist src;
+	struct scatterlist dst;
+	struct geniv_req_ctx *rctx;
+	struct skcipher_request req CRYPTO_MINALIGN_ATTR;
+};
+
+struct geniv_req_ctx {
+	struct geniv_subreq *subreq;
+	int is_write;
+	sector_t iv_sector;
+	unsigned int nents;
+	struct completion restart;
+	atomic_t req_pending;
+	struct skcipher_request *req;
+};
+
+struct crypt_iv_operations {
+	int (*ctr)(struct geniv_ctx *ctx);
+	void (*dtr)(struct geniv_ctx *ctx);
+	int (*init)(struct geniv_ctx *ctx);
+	int (*wipe)(struct geniv_ctx *ctx);
+	int (*generator)(struct geniv_ctx *ctx,
+			 struct geniv_req_ctx *rctx,
+			 struct geniv_subreq *subreq, u8 *iv);
+	int (*post)(struct geniv_ctx *ctx,
+		    struct geniv_req_ctx *rctx,
+		    struct geniv_subreq *subreq, u8 *iv);
+};
+
+struct geniv_ctx {
+	unsigned int tfms_count;
+	struct crypto_skcipher *child;
+	struct crypto_skcipher **tfms;
+	char *ivmode;
+	unsigned int iv_size;
+	unsigned int iv_start;
+	char *algname;
+	char *ivopts;
+	char *cipher;
+	char *ciphermode;
+	const struct crypt_iv_operations *iv_gen_ops;
+	void *iv_private;
+	struct crypto_skcipher *tfm;
+	mempool_t *subreq_pool;
+	unsigned int key_size;
+	unsigned int key_extra_size;
+	unsigned int key_parts;      /* independent parts in key buffer */
+	enum setkey_op keyop;
+	char *msg;
+	u8 *key;
+};
+
+static inline
+struct geniv_req_ctx *geniv_req_ctx(struct skcipher_request *req)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	unsigned long align = crypto_skcipher_alignmask(tfm);
+
+	return (void *) PTR_ALIGN((u8 *) skcipher_request_ctx(req), align + 1);
+}
+
+static u8 *iv_of_subreq(struct geniv_ctx *ctx, struct geniv_subreq *subreq)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(subreq->rctx->req);
+	return (u8*) ALIGN((unsigned long) ((char *) subreq + ctx->iv_start),
+			   crypto_skcipher_alignmask(tfm) + 1);
+}
+
+/*
+ * Different IV generation algorithms:
+ *
+ * essiv: "encrypted sector|salt initial vector", the sector number is
+ *        encrypted with the bulk cipher using a salt as key. The salt
+ *        should be derived from the bulk cipher's key via hashing.
+ *
+ */
+
+static int crypt_iv_essiv_gen(struct geniv_ctx *ctx,
+			      struct geniv_req_ctx *rctx,
+			      struct geniv_subreq *subreq, u8 *iv)
+{
+	memset(iv, 0, ctx->iv_size);
+	*(__le64 *)iv = cpu_to_le64(rctx->iv_sector);
+
+	return 0;
+}
+
+static const struct crypt_iv_operations crypt_iv_essiv_ops = {
+	.generator = crypt_iv_essiv_gen
+};
+
+static int geniv_setkey_set(struct geniv_ctx *ctx)
+{
+	int ret = 0;
+
+	if (ctx->iv_gen_ops && ctx->iv_gen_ops->init)
+		ret = ctx->iv_gen_ops->init(ctx);
+	return ret;
+}
+
+static int geniv_setkey_wipe(struct geniv_ctx *ctx)
+{
+	int ret = 0;
+
+	if (ctx->iv_gen_ops && ctx->iv_gen_ops->wipe) {
+		ret = ctx->iv_gen_ops->wipe(ctx);
+		if (ret)
+			return ret;
+	}
+	return ret;
+}
+
+static int geniv_init_iv(struct geniv_ctx *ctx)
+{
+	int ret = -EINVAL;
+
+	DMDEBUG("IV Generation algorithm : %s\n", ctx->ivmode);
+
+	if (ctx->ivmode == NULL)
+		ctx->iv_gen_ops = NULL;
+	else if (strcmp(ctx->ivmode, "essiv") == 0)
+		ctx->iv_gen_ops = &crypt_iv_essiv_ops;
+	else {
+		ret = -EINVAL;
+		DMERR("Invalid IV mode %s\n", ctx->ivmode);
+		goto end;
+	}
+
+	/* Allocate IV */
+	if (ctx->iv_gen_ops && ctx->iv_gen_ops->ctr) {
+		ret = ctx->iv_gen_ops->ctr(ctx);
+		if (ret < 0) {
+			DMERR("Error creating IV for %s\n", ctx->ivmode);
+			goto end;
+		}
+	}
+
+	/* Initialize IV (set keys for ESSIV etc) */
+	if (ctx->iv_gen_ops && ctx->iv_gen_ops->init) {
+		ret = ctx->iv_gen_ops->init(ctx);
+		if (ret < 0)
+			DMERR("Error creating IV for %s\n", ctx->ivmode);
+	}
+	ret = 0;
+end:
+	return ret;
+}
+
+static void geniv_free_tfms(struct geniv_ctx *ctx)
+{
+	unsigned int i;
+
+	if (!ctx->tfms)
+		return;
+
+	for (i = 0; i < ctx->tfms_count; i++)
+		if (ctx->tfms[i] && !IS_ERR(ctx->tfms[i])) {
+			crypto_free_skcipher(ctx->tfms[i]);
+			ctx->tfms[i] = NULL;
+		}
+
+	kfree(ctx->tfms);
+	ctx->tfms = NULL;
+}
+
+/* Allocate memory for the underlying cipher algorithm. Ex: cbc(aes)
+ */
+
+static int geniv_alloc_tfms(struct crypto_skcipher *parent,
+			    struct geniv_ctx *ctx)
+{
+	unsigned int i, reqsize, align;
+	int err = 0;
+
+	ctx->tfms = kcalloc(ctx->tfms_count, sizeof(struct crypto_skcipher *),
+			   GFP_KERNEL);
+	if (!ctx->tfms) {
+		err = -ENOMEM;
+		goto end;
+	}
+
+	/* First instance is already allocated in geniv_init_tfm */
+	ctx->tfms[0] = ctx->child;
+	for (i = 1; i < ctx->tfms_count; i++) {
+		ctx->tfms[i] = crypto_alloc_skcipher(ctx->ciphermode, 0, 0);
+		if (IS_ERR(ctx->tfms[i])) {
+			err = PTR_ERR(ctx->tfms[i]);
+			geniv_free_tfms(ctx);
+			goto end;
+		}
+
+		/* Setup the current cipher's request structure */
+		align = crypto_skcipher_alignmask(parent);
+		align &= ~(crypto_tfm_ctx_alignment() - 1);
+		reqsize = align + sizeof(struct geniv_req_ctx) +
+			  crypto_skcipher_reqsize(ctx->tfms[i]);
+		crypto_skcipher_set_reqsize(parent, reqsize);
+	}
+
+end:
+	return err;
+}
+
+/* Initialize the cipher's context with the key, ivmode and other parameters.
+ * Also allocate IV generation template ciphers and initialize them.
+ */
+
+static int geniv_setkey_init(struct crypto_skcipher *parent,
+			     struct geniv_key_info *info)
+{
+	struct geniv_ctx *ctx = crypto_skcipher_ctx(parent);
+	int ret = -ENOMEM;
+
+	if (info->tfms_count > 1) {
+		DMERR("Cannot use keycount > 1 for this cipher\n");
+		ret = -EINVAL;
+		goto end;
+	}
+	ctx->tfms_count = info->tfms_count;
+	ctx->key = info->key;
+	ctx->key_size = info->key_size;
+	ctx->key_parts = info->key_parts;
+	ctx->ivopts = info->ivopts;
+
+	ret = geniv_alloc_tfms(parent, ctx);
+	if (ret)
+		goto end;
+
+	ret = geniv_init_iv(ctx);
+
+end:
+	return ret;
+}
+
+static int geniv_setkey_tfms(struct crypto_skcipher *parent,
+			     struct geniv_ctx *ctx,
+			     struct geniv_key_info *info)
+{
+	unsigned int subkey_size;
+	int ret = 0, i;
+
+	/* Ignore extra keys (which are used for IV etc) */
+	subkey_size = (ctx->key_size - ctx->key_extra_size)
+		      >> ilog2(ctx->tfms_count);
+
+	for (i = 0; i < ctx->tfms_count; i++) {
+		struct crypto_skcipher *child = ctx->tfms[i];
+		char *subkey = ctx->key + (subkey_size) * i;
+
+		crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
+		crypto_skcipher_set_flags(child,
+					  crypto_skcipher_get_flags(parent) &
+					  CRYPTO_TFM_REQ_MASK);
+		ret = crypto_skcipher_setkey(child, subkey, subkey_size);
+		if (ret) {
+			DMERR("Error setting key for tfms[%d]\n", i);
+			break;
+		}
+		crypto_skcipher_set_flags(parent,
+					  crypto_skcipher_get_flags(child) &
+					  CRYPTO_TFM_RES_MASK);
+	}
+
+	return ret;
+}
+
+static int geniv_setkey(struct crypto_skcipher *parent,
+			const u8 *key, unsigned int keylen)
+{
+	int err = 0;
+	struct geniv_ctx *ctx = crypto_skcipher_ctx(parent);
+	struct geniv_key_info *info = (struct geniv_key_info *) key;
+
+	DMDEBUG("SETKEY Operation : %d\n", info->keyop);
+
+	switch (info->keyop) {
+	case SETKEY_OP_INIT:
+		err = geniv_setkey_init(parent, info);
+		break;
+	case SETKEY_OP_SET:
+		err = geniv_setkey_set(ctx);
+		break;
+	case SETKEY_OP_WIPE:
+		err = geniv_setkey_wipe(ctx);
+		break;
+	}
+
+	if (err)
+		goto end;
+
+	err = geniv_setkey_tfms(parent, ctx, info);
+
+end:
+	return err;
+}
+
+static void geniv_async_done(struct crypto_async_request *async_req, int error);
+
+static int geniv_alloc_subreq(struct skcipher_request *req,
+			      struct geniv_ctx *ctx,
+			      struct geniv_req_ctx *rctx)
+{
+	int key_index, r = 0;
+	struct skcipher_request *sreq;
+
+	if (!rctx->subreq) {
+		rctx->subreq = mempool_alloc(ctx->subreq_pool, GFP_NOIO);
+		if (!rctx->subreq)
+			r = -ENOMEM;
+	}
+
+	sreq = &rctx->subreq->req;
+	rctx->subreq->rctx = rctx;
+
+	key_index = rctx->iv_sector & (ctx->tfms_count - 1);
+
+	skcipher_request_set_tfm(sreq, ctx->tfms[key_index]);
+	skcipher_request_set_callback(sreq, req->base.flags,
+				      geniv_async_done, rctx->subreq);
+	return r;
+}
+
+/* Asynchronous IO completion callback for each sector in a segment. When all
+ * pending i/o are completed the parent cipher's async function is called.
+ */
+
+static void geniv_async_done(struct crypto_async_request *async_req, int error)
+{
+	struct geniv_subreq *subreq =
+		(struct geniv_subreq *) async_req->data;
+	struct geniv_req_ctx *rctx = subreq->rctx;
+	struct skcipher_request *req = rctx->req;
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	struct geniv_ctx *ctx = crypto_skcipher_ctx(tfm);
+	u8 *iv;
+
+	/*
+	 * A request from crypto driver backlog is going to be processed now,
+	 * finish the completion and continue in crypt_convert().
+	 * (Callback will be called for the second time for this request.)
+	 */
+
+	if (error == -EINPROGRESS) {
+		complete(&rctx->restart);
+		return;
+	}
+
+	iv = iv_of_subreq(ctx, subreq);
+	if (!error && ctx->iv_gen_ops && ctx->iv_gen_ops->post)
+		error = ctx->iv_gen_ops->post(ctx, rctx, subreq, iv);
+
+	mempool_free(subreq, ctx->subreq_pool);
+
+	/* req_pending needs to be checked before req->base.complete is called
+	 * as we need 'req_pending' to be equal to 1 to ensure all subrequests
+	 * are processed.
+	 */
+	if (!atomic_dec_and_test(&rctx->req_pending)) {
+		/* Call the parent cipher's completion function */
+		skcipher_request_complete(req, error);
+	}
+}
+
+
+/* Common encryt/decrypt function for geniv template cipher. Before the crypto
+ * operation, it splits the memory segments (in the scatterlist) into 512 byte
+ * sectors. The initialization vector(IV) used is based on a unique sector
+ * number which is generated here.
+ */
+static int geniv_crypt(struct skcipher_request *req, int encrypt)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	struct geniv_ctx *ctx = crypto_skcipher_ctx(tfm);
+	struct geniv_req_ctx *rctx = geniv_req_ctx(req);
+	struct geniv_req_info *rinfo = (struct geniv_req_info *) req->iv;
+	int ret = 0;
+	char *str __maybe_unused = encrypt ? "encrypt" : "decrypt";
+	u8 *iv;
+
+	/* Instance of 'struct geniv_req_info' is stored in IV ptr */
+	rctx->is_write = encrypt;
+	rctx->iv_sector = rinfo->iv_sector;
+	rctx->nents = rinfo->nents;
+	rctx->req = req;
+	rctx->subreq = NULL;
+
+	DMDEBUG("geniv:%s: starting sector=%d, #segments=%u\n", str,
+		(unsigned int) rctx->iv_sector, rctx->nents);
+
+	init_completion(&rctx->restart);
+	atomic_set(&rctx->req_pending, 1);
+
+	struct geniv_subreq *subreq;
+
+	ret = geniv_alloc_subreq(req, ctx, rctx);
+	if (ret)
+		goto end;
+
+	subreq = rctx->subreq;
+	subreq->rctx = rctx;
+	iv = iv_of_subreq(ctx, subreq);
+
+	atomic_inc(&rctx->req_pending);
+
+	if (ctx->iv_gen_ops)
+		ret = ctx->iv_gen_ops->generator(ctx, rctx, subreq, iv);
+
+	if (ret < 0) {
+		DMERR("Error in generating IV ret: %d\n", ret);
+		goto end;
+	}
+
+	skcipher_request_set_crypt(&subreq->req, req->src,
+				   req->dst, req->cryptlen, iv);
+
+	if (encrypt)
+		ret = crypto_skcipher_encrypt(&subreq->req);
+
+	else
+		ret = crypto_skcipher_decrypt(&subreq->req);
+
+	switch (ret) {
+	/*
+	 * The request was queued by a crypto driver
+	 * but the driver request queue is full, let's wait.
+	 */
+	case -EBUSY:
+		wait_for_completion(&rctx->restart);
+		reinit_completion(&rctx->restart);
+		/* fall through */
+	/*
+	 * The request is queued and processed asynchronously,
+	 * completion function geniv_async_done() is called.
+	 */
+	case -EINPROGRESS:
+		/* Marking this NULL lets the creation of a new sub-
+		 * request when 'geniv_alloc_subreq' is called.
+		 */
+		rctx->subreq = NULL;
+		rctx->iv_sector++;
+		cond_resched();
+		break;
+	/*
+	 * The request was already processed (synchronously).
+	 */
+	case 0:
+		atomic_dec(&rctx->req_pending);
+		rctx->iv_sector++;
+		cond_resched();
+		break;
+
+	/* There was an error while processing the request. */
+	default:
+		atomic_dec(&rctx->req_pending);
+		return ret;
+	}
+
+	if (rctx->subreq && atomic_read(&rctx->req_pending) == 1) {
+		DMDEBUG("geniv:%s: Freeing sub request\n", str);
+		mempool_free(rctx->subreq, ctx->subreq_pool);
+	}
+
+end:
+	return ret;
+}
+
+static int geniv_encrypt(struct skcipher_request *req)
+{
+	return geniv_crypt(req, 1);
+}
+
+static int geniv_decrypt(struct skcipher_request *req)
+{
+	return geniv_crypt(req, 0);
+}
+
+static int geniv_init_tfm(struct crypto_skcipher *tfm)
+{
+	struct geniv_ctx *ctx = crypto_skcipher_ctx(tfm);
+	unsigned int reqsize, align;
+	size_t iv_size_padding;
+	char *algname, *chainmode;
+	int psize, ret = 0;
+
+	algname = (char *) crypto_tfm_alg_name(crypto_skcipher_tfm(tfm));
+	ctx->ciphermode = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
+	if (!ctx->ciphermode) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ctx->algname = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
+	if (!ctx->algname) {
+		ret = -ENOMEM;
+		goto free_ciphermode;
+	}
+
+	strlcpy(ctx->algname, algname, CRYPTO_MAX_ALG_NAME);
+	algname = ctx->algname;
+
+	/* Parse the algorithm name 'ivmode(chainmode(cipher))' */
+	ctx->ivmode	= strsep(&algname, "(");
+	chainmode	= strsep(&algname, "(");
+	ctx->cipher	= strsep(&algname, ")");
+
+	if (strcmp(ctx->ivmode, "essiv") == 0)
+		// strlcpy(ctx->ciphermode, "essiv-aes-du512-dx", CRYPTO_MAX_ALG_NAME);
+		snprintf(ctx->ciphermode, CRYPTO_MAX_ALG_NAME, "%s(%s)",
+			chainmode, ctx->cipher);
+	else {
+		ret = -EINVAL;
+		DMERR("Invalid IV mode %s\n", ctx->ivmode);
+		goto free_algname;
+	}
+
+	DMDEBUG("ciphermode=%s, ivmode=%s\n", ctx->ciphermode, ctx->ivmode);
+
+	/*
+	 * Usually the underlying cipher instances are spawned here, but since
+	 * the value of tfms_count (which is equal to the key_count) is not
+	 * known yet, create only one instance and delay the creation of the
+	 * rest of the instances of the underlying cipher 'cbc(aes)' until
+	 * the setkey operation is invoked.
+	 * The first instance created i.e. ctx->child will later be assigned as
+	 * the 1st element in the array ctx->tfms. Creation of atleast one
+	 * instance of the cipher is necessary to be created here to uncover
+	 * any errors earlier than during the setkey operation later where the
+	 * remaining instances are created.
+	 */
+	ctx->child = crypto_alloc_skcipher(ctx->ciphermode, 0, 0);
+	if (IS_ERR(ctx->child)) {
+		ret = PTR_ERR(ctx->child);
+		DMERR("Failed to create skcipher %s. err %d\n",
+		      ctx->ciphermode, ret);
+		goto free_algname;
+	}
+
+	/* Setup the current cipher's request structure */
+	align = crypto_skcipher_alignmask(tfm);
+	align &= ~(crypto_tfm_ctx_alignment() - 1);
+	reqsize = align + sizeof(struct geniv_req_ctx)
+			+ crypto_skcipher_reqsize(ctx->child);
+	crypto_skcipher_set_reqsize(tfm, reqsize);
+
+	ctx->iv_start = sizeof(struct geniv_subreq);
+	ctx->iv_start += crypto_skcipher_reqsize(tfm);
+
+	ctx->iv_size = crypto_skcipher_ivsize(tfm);
+	/* at least a 64 bit sector number should fit in our buffer */
+	if (ctx->iv_size)
+		ctx->iv_size = max(ctx->iv_size,
+				  (unsigned int)(sizeof(u64) / sizeof(u8)));
+
+	if (crypto_skcipher_alignmask(tfm) < CRYPTO_MINALIGN) {
+		/* Allocate the padding exactly */
+		iv_size_padding = -ctx->iv_start
+				& crypto_skcipher_alignmask(tfm);
+	} else {
+		/*
+		 * If the cipher requires greater alignment than kmalloc
+		 * alignment, we don't know the exact position of the
+		 * initialization vector. We must assume worst case.
+		 */
+		iv_size_padding = crypto_skcipher_alignmask(tfm);
+	}
+
+	/* create memory pool for sub-request structure */
+	psize = ctx->iv_start + iv_size_padding + ctx->iv_size;
+
+	ctx->subreq_pool = mempool_create_kmalloc_pool(MIN_IOS, psize);
+	if (!ctx->subreq_pool) {
+		ret = -ENOMEM;
+		DMERR("Could not allocate crypt sub-request mempool\n");
+		goto free_skcipher;
+	}
+out:
+	return ret;
+
+free_skcipher:
+	crypto_free_skcipher(ctx->child);
+free_algname:
+	kfree(ctx->algname);
+free_ciphermode:
+	kfree(ctx->ciphermode);
+	goto out;
+}
+
+static void geniv_exit_tfm(struct crypto_skcipher *tfm)
+{
+	struct geniv_ctx *ctx = crypto_skcipher_ctx(tfm);
+
+	if (ctx->iv_gen_ops && ctx->iv_gen_ops->dtr)
+		ctx->iv_gen_ops->dtr(ctx);
+
+	mempool_destroy(ctx->subreq_pool);
+	geniv_free_tfms(ctx);
+	kfree(ctx->ciphermode);
+	kfree(ctx->algname);
+}
+
+static void geniv_free(struct skcipher_instance *inst)
+{
+	struct crypto_skcipher_spawn *spawn = skcipher_instance_ctx(inst);
+
+	crypto_drop_skcipher(spawn);
+	kfree(inst);
+}
+
+static int geniv_create(struct crypto_template *tmpl,
+			struct rtattr **tb, char *algname)
+{
+	struct crypto_attr_type *algt;
+	struct skcipher_instance *inst;
+	struct skcipher_alg *alg;
+	struct crypto_skcipher_spawn *spawn;
+	const char *cipher_name;
+	int err;
+
+	algt = crypto_get_attr_type(tb);
+
+	if (IS_ERR(algt))
+		return PTR_ERR(algt);
+
+	if ((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask)
+		return -EINVAL;
+
+	cipher_name = crypto_attr_alg_name(tb[1]);
+
+	if (IS_ERR(cipher_name))
+		return PTR_ERR(cipher_name);
+
+	inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
+	if (!inst)
+		return -ENOMEM;
+
+	spawn = skcipher_instance_ctx(inst);
+
+	crypto_set_skcipher_spawn(spawn, skcipher_crypto_instance(inst));
+	err = crypto_grab_skcipher(spawn, cipher_name, 0,
+				    crypto_requires_sync(algt->type,
+							 algt->mask));
+
+	if (err)
+		goto err_free_inst;
+
+	alg = crypto_spawn_skcipher_alg(spawn);
+
+	err = -EINVAL;
+
+	/* Only support blocks of size which is of a power of 2 */
+	if (!is_power_of_2(alg->base.cra_blocksize))
+		goto err_drop_spawn;
+
+	/* algname: essiv, base.cra_name: cbc(aes) */
+	err = -ENAMETOOLONG;
+	if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
+		     algname, alg->base.cra_name) >= CRYPTO_MAX_ALG_NAME)
+		goto err_drop_spawn;
+	if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
+		     "%s(%s)", algname, alg->base.cra_driver_name) >=
+	    CRYPTO_MAX_ALG_NAME)
+		goto err_drop_spawn;
+
+	inst->alg.base.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER;
+	inst->alg.base.cra_priority = alg->base.cra_priority;
+	inst->alg.base.cra_blocksize = alg->base.cra_blocksize;
+	inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
+	inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
+	inst->alg.ivsize = alg->base.cra_blocksize;
+	inst->alg.chunksize = crypto_skcipher_alg_chunksize(alg);
+	inst->alg.min_keysize = crypto_skcipher_alg_min_keysize(alg);
+	inst->alg.max_keysize = crypto_skcipher_alg_max_keysize(alg);
+
+	inst->alg.setkey = geniv_setkey;
+	inst->alg.encrypt = geniv_encrypt;
+	inst->alg.decrypt = geniv_decrypt;
+
+	inst->alg.base.cra_ctxsize = sizeof(struct geniv_ctx);
+
+	inst->alg.init = geniv_init_tfm;
+	inst->alg.exit = geniv_exit_tfm;
+
+	inst->free = geniv_free;
+
+	err = skcipher_register_instance(tmpl, inst);
+	if (err)
+		goto err_drop_spawn;
+
+out:
+	return err;
+
+err_drop_spawn:
+	crypto_drop_skcipher(spawn);
+err_free_inst:
+	kfree(inst);
+	goto out;
+}
+
+static int crypto_essiv_create(struct crypto_template *tmpl,
+			       struct rtattr **tb)
+{
+	return geniv_create(tmpl, tb, "essiv");
+}
+
+static struct crypto_template crypto_essiv_tmpl = {
+	.name   = "essiv",
+	.create = crypto_essiv_create,
+	.module = THIS_MODULE,
+};
+
+static int __init essiv_init(void)
+{
+	return crypto_register_template(&crypto_essiv_tmpl);
+}
+
+static void __exit essiv_exit(void)
+{
+	crypto_unregister_template(&crypto_essiv_tmpl);
+}
+
+module_init(essiv_init);
+module_exit(essiv_exit);
+
+MODULE_AUTHOR("Binoy Jayan <binoy.jayan@linaro.org>");
+MODULE_DESCRIPTION(DM_NAME " essiv implementation for cryptocell 712");
+MODULE_LICENSE("GPL");
diff --git a/drivers/staging/ccree/essiv_sw.c b/drivers/staging/ccree/essiv_sw.c
new file mode 100644
index 0000000..f07956f
--- /dev/null
+++ b/drivers/staging/ccree/essiv_sw.c
@@ -0,0 +1,1040 @@ 
+/*
+ * Copyright (C) 2003 Jana Saout <jana@saout.de>
+ * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org>
+ * Copyright (C) 2006-2015 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2013 Milan Broz <gmazyland@gmail.com>
+ *
+ * This file is released under the GPL.
+ */
+
+#include <linux/completion.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/key.h>
+#include <linux/bio.h>
+#include <linux/blkdev.h>
+#include <linux/mempool.h>
+#include <linux/slab.h>
+#include <linux/crypto.h>
+#include <linux/workqueue.h>
+#include <linux/kthread.h>
+#include <linux/backing-dev.h>
+#include <linux/atomic.h>
+#include <linux/scatterlist.h>
+#include <linux/rbtree.h>
+#include <linux/ctype.h>
+#include <asm/page.h>
+#include <asm/unaligned.h>
+#include <crypto/hash.h>
+#include <crypto/md5.h>
+#include <crypto/algapi.h>
+#include <crypto/skcipher.h>
+#include <keys/user-type.h>
+#include <linux/device-mapper.h>
+#include <crypto/internal/skcipher.h>
+#include <linux/backing-dev.h>
+#include <linux/log2.h>
+#include <crypto/geniv.h>
+
+#define DM_MSG_PREFIX		"crypt"
+#define MAX_SG_LIST		(BIO_MAX_PAGES * 8)
+#define MIN_IOS			64
+#define LMK_SEED_SIZE		64 /* hash + 0 */
+#define TCW_WHITENING_SIZE	16
+
+struct geniv_ctx;
+struct geniv_req_ctx;
+
+/* Sub request for each of the skcipher_request's for a segment */
+struct geniv_subreq {
+	struct scatterlist src;
+	struct scatterlist dst;
+	struct geniv_req_ctx *rctx;
+	struct skcipher_request req CRYPTO_MINALIGN_ATTR;
+};
+
+struct geniv_req_ctx {
+	struct geniv_subreq *subreq;
+	int is_write;
+	sector_t iv_sector;
+	unsigned int nents;
+	struct completion restart;
+	atomic_t req_pending;
+	struct skcipher_request *req;
+};
+
+struct crypt_iv_operations {
+	int (*ctr)(struct geniv_ctx *ctx);
+	void (*dtr)(struct geniv_ctx *ctx);
+	int (*init)(struct geniv_ctx *ctx);
+	int (*wipe)(struct geniv_ctx *ctx);
+	int (*generator)(struct geniv_ctx *ctx,
+			 struct geniv_req_ctx *rctx,
+			 struct geniv_subreq *subreq, u8 *iv);
+	int (*post)(struct geniv_ctx *ctx,
+		    struct geniv_req_ctx *rctx,
+		    struct geniv_subreq *subreq, u8 *iv);
+};
+
+struct geniv_essiv_private {
+	struct crypto_ahash *hash_tfm;
+	u8 *salt;
+};
+
+struct geniv_benbi_private {
+	int shift;
+};
+
+struct geniv_lmk_private {
+	struct crypto_shash *hash_tfm;
+	u8 *seed;
+};
+
+struct geniv_tcw_private {
+	struct crypto_shash *crc32_tfm;
+	u8 *iv_seed;
+	u8 *whitening;
+};
+
+struct geniv_ctx {
+	unsigned int tfms_count;
+	struct crypto_skcipher *child;
+	struct crypto_skcipher **tfms;
+	char *ivmode;
+	unsigned int iv_size;
+	unsigned int iv_start;
+	char *algname;
+	char *ivopts;
+	char *cipher;
+	char *ciphermode;
+	const struct crypt_iv_operations *iv_gen_ops;
+	union {
+		struct geniv_essiv_private essiv;
+		struct geniv_benbi_private benbi;
+		struct geniv_lmk_private lmk;
+		struct geniv_tcw_private tcw;
+	} iv_gen_private;
+	void *iv_private;
+	struct crypto_skcipher *tfm;
+	mempool_t *subreq_pool;
+	unsigned int key_size;
+	unsigned int key_extra_size;
+	unsigned int key_parts;      /* independent parts in key buffer */
+	enum setkey_op keyop;
+	char *msg;
+	u8 *key;
+};
+
+static struct crypto_skcipher *any_tfm(struct geniv_ctx *ctx)
+{
+	return ctx->tfms[0];
+}
+
+static inline
+struct geniv_req_ctx *geniv_req_ctx(struct skcipher_request *req)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	unsigned long align = crypto_skcipher_alignmask(tfm);
+
+	return (void *) PTR_ALIGN((u8 *) skcipher_request_ctx(req), align + 1);
+}
+
+static u8 *iv_of_subreq(struct geniv_ctx *ctx, struct geniv_subreq *subreq)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(subreq->rctx->req);
+	return (u8*) ALIGN((unsigned long) ((char *) subreq + ctx->iv_start),
+			   crypto_skcipher_alignmask(tfm) + 1);
+}
+
+/*
+ * Different IV generation algorithms:
+ *
+ * essiv: "encrypted sector|salt initial vector", the sector number is
+ *        encrypted with the bulk cipher using a salt as key. The salt
+ *        should be derived from the bulk cipher's key via hashing.
+ *
+ * plumb: unimplemented, see:
+ * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454
+ */
+
+/* Initialise ESSIV - compute salt but no local memory allocations */
+static int crypt_iv_essiv_init(struct geniv_ctx *ctx)
+{
+	struct geniv_essiv_private *essiv = &ctx->iv_gen_private.essiv;
+	struct scatterlist sg;
+	struct crypto_cipher *essiv_tfm;
+	int err;
+	AHASH_REQUEST_ON_STACK(req, essiv->hash_tfm);
+
+	sg_init_one(&sg, ctx->key, ctx->key_size);
+	ahash_request_set_tfm(req, essiv->hash_tfm);
+	ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
+	ahash_request_set_crypt(req, &sg, essiv->salt, ctx->key_size);
+
+	err = crypto_ahash_digest(req);
+	ahash_request_zero(req);
+	if (err)
+		return err;
+
+	essiv_tfm = ctx->iv_private;
+
+	err = crypto_cipher_setkey(essiv_tfm, essiv->salt,
+			    crypto_ahash_digestsize(essiv->hash_tfm));
+	if (err)
+		return err;
+
+	return 0;
+}
+
+/* Wipe salt and reset key derived from volume key */
+static int crypt_iv_essiv_wipe(struct geniv_ctx *ctx)
+{
+	struct geniv_essiv_private *essiv = &ctx->iv_gen_private.essiv;
+	unsigned int salt_size = crypto_ahash_digestsize(essiv->hash_tfm);
+	struct crypto_cipher *essiv_tfm;
+	int r, err = 0;
+
+	memset(essiv->salt, 0, salt_size);
+
+	essiv_tfm = ctx->iv_private;
+	r = crypto_cipher_setkey(essiv_tfm, essiv->salt, salt_size);
+	if (r)
+		err = r;
+
+	return err;
+}
+
+/* Set up per cpu cipher state */
+static struct crypto_cipher *setup_essiv_cpu(struct geniv_ctx *ctx,
+					     u8 *salt, unsigned int saltsize)
+{
+	struct crypto_cipher *essiv_tfm;
+	int err;
+
+	/* Setup the essiv_tfm with the given salt */
+	essiv_tfm = crypto_alloc_cipher(ctx->cipher, 0, CRYPTO_ALG_ASYNC);
+
+	if (IS_ERR(essiv_tfm)) {
+		DMERR("Error allocating crypto tfm for ESSIV\n");
+		return essiv_tfm;
+	}
+
+	if (crypto_cipher_blocksize(essiv_tfm) !=
+	    crypto_skcipher_ivsize(any_tfm(ctx))) {
+		DMERR("Block size of ESSIV cipher does not match IV size of block cipher\n");
+		crypto_free_cipher(essiv_tfm);
+		return ERR_PTR(-EINVAL);
+	}
+
+	err = crypto_cipher_setkey(essiv_tfm, salt, saltsize);
+	if (err) {
+		DMERR("Failed to set key for ESSIV cipher\n");
+		crypto_free_cipher(essiv_tfm);
+		return ERR_PTR(err);
+	}
+	return essiv_tfm;
+}
+
+static void crypt_iv_essiv_dtr(struct geniv_ctx *ctx)
+{
+	struct crypto_cipher *essiv_tfm;
+	struct geniv_essiv_private *essiv = &ctx->iv_gen_private.essiv;
+
+	crypto_free_ahash(essiv->hash_tfm);
+	essiv->hash_tfm = NULL;
+
+	kzfree(essiv->salt);
+	essiv->salt = NULL;
+
+	essiv_tfm = ctx->iv_private;
+
+	if (essiv_tfm)
+		crypto_free_cipher(essiv_tfm);
+
+	ctx->iv_private = NULL;
+}
+
+static int crypt_iv_essiv_ctr(struct geniv_ctx *ctx)
+{
+	struct crypto_cipher *essiv_tfm = NULL;
+	struct crypto_ahash *hash_tfm = NULL;
+	u8 *salt = NULL;
+	int err;
+
+	if (!ctx->ivopts) {
+		DMERR("Digest algorithm missing for ESSIV mode\n");
+		return -EINVAL;
+	}
+
+	/* Allocate hash algorithm */
+	hash_tfm = crypto_alloc_ahash(ctx->ivopts, 0, CRYPTO_ALG_ASYNC);
+	if (IS_ERR(hash_tfm)) {
+		err = PTR_ERR(hash_tfm);
+		DMERR("Error initializing ESSIV hash. err=%d\n", err);
+		goto bad;
+	}
+
+	salt = kzalloc(crypto_ahash_digestsize(hash_tfm), GFP_KERNEL);
+	if (!salt) {
+		err = -ENOMEM;
+		goto bad;
+	}
+
+	ctx->iv_gen_private.essiv.salt = salt;
+	ctx->iv_gen_private.essiv.hash_tfm = hash_tfm;
+
+	essiv_tfm = setup_essiv_cpu(ctx, salt,
+				crypto_ahash_digestsize(hash_tfm));
+	if (IS_ERR(essiv_tfm)) {
+		crypt_iv_essiv_dtr(ctx);
+		return PTR_ERR(essiv_tfm);
+	}
+	ctx->iv_private = essiv_tfm;
+
+	return 0;
+
+bad:
+	if (hash_tfm && !IS_ERR(hash_tfm))
+		crypto_free_ahash(hash_tfm);
+	kfree(salt);
+	return err;
+}
+
+static int crypt_iv_essiv_gen(struct geniv_ctx *ctx,
+			      struct geniv_req_ctx *rctx,
+			      struct geniv_subreq *subreq, u8 *iv)
+{
+	struct crypto_cipher *essiv_tfm = ctx->iv_private;
+
+	memset(iv, 0, ctx->iv_size);
+	*(__le64 *)iv = cpu_to_le64(rctx->iv_sector);
+	crypto_cipher_encrypt_one(essiv_tfm, iv, iv);
+
+	return 0;
+}
+
+static const struct crypt_iv_operations crypt_iv_essiv_ops = {
+	.ctr       = crypt_iv_essiv_ctr,
+	.dtr       = crypt_iv_essiv_dtr,
+	.init      = crypt_iv_essiv_init,
+	.wipe      = crypt_iv_essiv_wipe,
+	.generator = crypt_iv_essiv_gen
+};
+
+static int geniv_setkey_set(struct geniv_ctx *ctx)
+{
+	int ret = 0;
+
+	if (ctx->iv_gen_ops && ctx->iv_gen_ops->init)
+		ret = ctx->iv_gen_ops->init(ctx);
+	return ret;
+}
+
+static int geniv_setkey_wipe(struct geniv_ctx *ctx)
+{
+	int ret = 0;
+
+	if (ctx->iv_gen_ops && ctx->iv_gen_ops->wipe) {
+		ret = ctx->iv_gen_ops->wipe(ctx);
+		if (ret)
+			return ret;
+	}
+	return ret;
+}
+
+static int geniv_init_iv(struct geniv_ctx *ctx)
+{
+	int ret = -EINVAL;
+
+	DMDEBUG("IV Generation algorithm : %s\n", ctx->ivmode);
+
+	if (ctx->ivmode == NULL)
+		ctx->iv_gen_ops = NULL;
+	else if (strcmp(ctx->ivmode, "essiv") == 0)
+		ctx->iv_gen_ops = &crypt_iv_essiv_ops;
+	else {
+		ret = -EINVAL;
+		DMERR("Invalid IV mode %s\n", ctx->ivmode);
+		goto end;
+	}
+
+	/* Allocate IV */
+	if (ctx->iv_gen_ops && ctx->iv_gen_ops->ctr) {
+		ret = ctx->iv_gen_ops->ctr(ctx);
+		if (ret < 0) {
+			DMERR("Error creating IV for %s\n", ctx->ivmode);
+			goto end;
+		}
+	}
+
+	/* Initialize IV (set keys for ESSIV etc) */
+	if (ctx->iv_gen_ops && ctx->iv_gen_ops->init) {
+		ret = ctx->iv_gen_ops->init(ctx);
+		if (ret < 0)
+			DMERR("Error creating IV for %s\n", ctx->ivmode);
+	}
+	ret = 0;
+end:
+	return ret;
+}
+
+static void geniv_free_tfms(struct geniv_ctx *ctx)
+{
+	unsigned int i;
+
+	if (!ctx->tfms)
+		return;
+
+	for (i = 0; i < ctx->tfms_count; i++)
+		if (ctx->tfms[i] && !IS_ERR(ctx->tfms[i])) {
+			crypto_free_skcipher(ctx->tfms[i]);
+			ctx->tfms[i] = NULL;
+		}
+
+	kfree(ctx->tfms);
+	ctx->tfms = NULL;
+}
+
+/* Allocate memory for the underlying cipher algorithm. Ex: cbc(aes)
+ */
+
+static int geniv_alloc_tfms(struct crypto_skcipher *parent,
+			    struct geniv_ctx *ctx)
+{
+	unsigned int i, reqsize, align;
+	int err = 0;
+
+	ctx->tfms = kcalloc(ctx->tfms_count, sizeof(struct crypto_skcipher *),
+			   GFP_KERNEL);
+	if (!ctx->tfms) {
+		err = -ENOMEM;
+		goto end;
+	}
+
+	/* First instance is already allocated in geniv_init_tfm */
+	ctx->tfms[0] = ctx->child;
+	for (i = 1; i < ctx->tfms_count; i++) {
+		ctx->tfms[i] = crypto_alloc_skcipher(ctx->ciphermode, 0, 0);
+		if (IS_ERR(ctx->tfms[i])) {
+			err = PTR_ERR(ctx->tfms[i]);
+			geniv_free_tfms(ctx);
+			goto end;
+		}
+
+		/* Setup the current cipher's request structure */
+		align = crypto_skcipher_alignmask(parent);
+		align &= ~(crypto_tfm_ctx_alignment() - 1);
+		reqsize = align + sizeof(struct geniv_req_ctx) +
+			  crypto_skcipher_reqsize(ctx->tfms[i]);
+		crypto_skcipher_set_reqsize(parent, reqsize);
+	}
+
+end:
+	return err;
+}
+
+/* Initialize the cipher's context with the key, ivmode and other parameters.
+ * Also allocate IV generation template ciphers and initialize them.
+ */
+
+static int geniv_setkey_init(struct crypto_skcipher *parent,
+			     struct geniv_key_info *info)
+{
+	struct geniv_ctx *ctx = crypto_skcipher_ctx(parent);
+	int ret = -ENOMEM;
+
+	ctx->tfms_count = info->tfms_count;
+	ctx->key = info->key;
+	ctx->key_size = info->key_size;
+	ctx->key_parts = info->key_parts;
+	ctx->ivopts = info->ivopts;
+
+	ret = geniv_alloc_tfms(parent, ctx);
+	if (ret)
+		goto end;
+
+	ret = geniv_init_iv(ctx);
+
+end:
+	return ret;
+}
+
+static int geniv_setkey_tfms(struct crypto_skcipher *parent,
+			     struct geniv_ctx *ctx,
+			     struct geniv_key_info *info)
+{
+	unsigned int subkey_size;
+	int ret = 0, i;
+
+	/* Ignore extra keys (which are used for IV etc) */
+	subkey_size = (ctx->key_size - ctx->key_extra_size)
+		      >> ilog2(ctx->tfms_count);
+
+	for (i = 0; i < ctx->tfms_count; i++) {
+		struct crypto_skcipher *child = ctx->tfms[i];
+		char *subkey = ctx->key + (subkey_size) * i;
+
+		crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
+		crypto_skcipher_set_flags(child,
+					  crypto_skcipher_get_flags(parent) &
+					  CRYPTO_TFM_REQ_MASK);
+		ret = crypto_skcipher_setkey(child, subkey, subkey_size);
+		if (ret) {
+			DMERR("Error setting key for tfms[%d]\n", i);
+			break;
+		}
+		crypto_skcipher_set_flags(parent,
+					  crypto_skcipher_get_flags(child) &
+					  CRYPTO_TFM_RES_MASK);
+	}
+
+	return ret;
+}
+
+static int geniv_setkey(struct crypto_skcipher *parent,
+			const u8 *key, unsigned int keylen)
+{
+	int err = 0;
+	struct geniv_ctx *ctx = crypto_skcipher_ctx(parent);
+	struct geniv_key_info *info = (struct geniv_key_info *) key;
+
+	DMDEBUG("SETKEY Operation : %d\n", info->keyop);
+
+	switch (info->keyop) {
+	case SETKEY_OP_INIT:
+		err = geniv_setkey_init(parent, info);
+		break;
+	case SETKEY_OP_SET:
+		err = geniv_setkey_set(ctx);
+		break;
+	case SETKEY_OP_WIPE:
+		err = geniv_setkey_wipe(ctx);
+		break;
+	}
+
+	if (err)
+		goto end;
+
+	err = geniv_setkey_tfms(parent, ctx, info);
+
+end:
+	return err;
+}
+
+static void geniv_async_done(struct crypto_async_request *async_req, int error);
+
+static int geniv_alloc_subreq(struct skcipher_request *req,
+			      struct geniv_ctx *ctx,
+			      struct geniv_req_ctx *rctx)
+{
+	int key_index, r = 0;
+	struct skcipher_request *sreq;
+
+	if (!rctx->subreq) {
+		rctx->subreq = mempool_alloc(ctx->subreq_pool, GFP_NOIO);
+		if (!rctx->subreq)
+			r = -ENOMEM;
+	}
+
+	sreq = &rctx->subreq->req;
+	rctx->subreq->rctx = rctx;
+
+	key_index = rctx->iv_sector & (ctx->tfms_count - 1);
+
+	skcipher_request_set_tfm(sreq, ctx->tfms[key_index]);
+	skcipher_request_set_callback(sreq, req->base.flags,
+				      geniv_async_done, rctx->subreq);
+	return r;
+}
+
+/* Asynchronous IO completion callback for each sector in a segment. When all
+ * pending i/o are completed the parent cipher's async function is called.
+ */
+
+static void geniv_async_done(struct crypto_async_request *async_req, int error)
+{
+	struct geniv_subreq *subreq =
+		(struct geniv_subreq *) async_req->data;
+	struct geniv_req_ctx *rctx = subreq->rctx;
+	struct skcipher_request *req = rctx->req;
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	struct geniv_ctx *ctx = crypto_skcipher_ctx(tfm);
+	u8 *iv;
+
+	/*
+	 * A request from crypto driver backlog is going to be processed now,
+	 * finish the completion and continue in crypt_convert().
+	 * (Callback will be called for the second time for this request.)
+	 */
+
+	if (error == -EINPROGRESS) {
+		complete(&rctx->restart);
+		return;
+	}
+
+	iv = iv_of_subreq(ctx, subreq);
+	if (!error && ctx->iv_gen_ops && ctx->iv_gen_ops->post)
+		error = ctx->iv_gen_ops->post(ctx, rctx, subreq, iv);
+
+	mempool_free(subreq, ctx->subreq_pool);
+
+	/* req_pending needs to be checked before req->base.complete is called
+	 * as we need 'req_pending' to be equal to 1 to ensure all subrequests
+	 * are processed.
+	 */
+	if (!atomic_dec_and_test(&rctx->req_pending)) {
+		/* Call the parent cipher's completion function */
+		skcipher_request_complete(req, error);
+	}
+}
+
+static unsigned int geniv_get_sectors(struct scatterlist *sg1,
+				      struct scatterlist *sg2,
+				      unsigned int segments)
+{
+	unsigned int i, n1, n2, nents;
+
+	n1 = n2 = 0;
+	for (i = 0; i < segments ; i++) {
+		n1 += sg1[i].length >> SECTOR_SHIFT;
+		n1 += (sg1[i].length & ~SECTOR_MASK) ? 1 : 0;
+	}
+
+	for (i = 0; i < segments ; i++) {
+		n2 += sg2[i].length >> SECTOR_SHIFT;
+		n2 += (sg2[i].length & ~SECTOR_MASK) ? 1 : 0;
+	}
+
+	nents = n1 > n2 ? n1 : n2;
+	return nents;
+}
+
+/* Iterate scatterlist of segments to retrieve the 512-byte sectors so that
+ * unique IVs could be generated for each 512-byte sector. This split may not
+ * be necessary e.g. when these ciphers are modelled in hardware, where it can
+ * make use of the hardware's IV generation capabilities.
+ */
+
+static int geniv_iter_block(struct skcipher_request *req,
+			    struct geniv_subreq *subreq,
+			    struct geniv_req_ctx *rctx,
+			    unsigned int *seg_no,
+			    unsigned int *done)
+
+{
+	unsigned int srcoff, dstoff, len, rem;
+	struct scatterlist *src1, *dst1, *src2, *dst2;
+
+	if (unlikely(*seg_no >= rctx->nents))
+		return 0; /* done */
+
+	src1 = &req->src[*seg_no];
+	dst1 = &req->dst[*seg_no];
+	src2 = &subreq->src;
+	dst2 = &subreq->dst;
+
+	if (*done >= src1->length) {
+		(*seg_no)++;
+
+		if (*seg_no >= rctx->nents)
+			return 0; /* done */
+
+		src1 = &req->src[*seg_no];
+		dst1 = &req->dst[*seg_no];
+		*done = 0;
+	}
+
+	srcoff = src1->offset + *done;
+	dstoff = dst1->offset + *done;
+	rem = src1->length - *done;
+
+	len = rem > SECTOR_SIZE ? SECTOR_SIZE : rem;
+
+	DMDEBUG("segment:(%d/%u), srcoff:%d, dstoff:%d, done:%d, rem:%d\n",
+		*seg_no + 1, rctx->nents, srcoff, dstoff, *done, rem);
+
+	sg_init_table(src2, 1);
+	sg_set_page(src2, sg_page(src1), len, srcoff);
+	sg_init_table(dst2, 1);
+	sg_set_page(dst2, sg_page(dst1), len, dstoff);
+
+	*done += len;
+
+	return len; /* bytes returned */
+}
+
+/* Common encryt/decrypt function for geniv template cipher. Before the crypto
+ * operation, it splits the memory segments (in the scatterlist) into 512 byte
+ * sectors. The initialization vector(IV) used is based on a unique sector
+ * number which is generated here.
+ */
+static int geniv_crypt(struct skcipher_request *req, int encrypt)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	struct geniv_ctx *ctx = crypto_skcipher_ctx(tfm);
+	struct geniv_req_ctx *rctx = geniv_req_ctx(req);
+	struct geniv_req_info *rinfo = (struct geniv_req_info *) req->iv;
+	int i, bytes, cryptlen, ret = 0;
+	unsigned int sectors, segno = 0, done = 0;
+	char *str __maybe_unused = encrypt ? "encrypt" : "decrypt";
+	u8 *iv;
+
+	/* Instance of 'struct geniv_req_info' is stored in IV ptr */
+	rctx->is_write = encrypt;
+	rctx->iv_sector = rinfo->iv_sector;
+	rctx->nents = rinfo->nents;
+	rctx->req = req;
+	rctx->subreq = NULL;
+	cryptlen = req->cryptlen;
+
+	DMDEBUG("geniv:%s: starting sector=%d, #segments=%u\n", str,
+		(unsigned int) rctx->iv_sector, rctx->nents);
+
+	sectors = geniv_get_sectors(req->src, req->dst, rctx->nents);
+
+	init_completion(&rctx->restart);
+	atomic_set(&rctx->req_pending, 1);
+
+	for (i = 0; i < sectors; i++) {
+		struct geniv_subreq *subreq;
+
+		ret = geniv_alloc_subreq(req, ctx, rctx);
+		if (ret)
+			goto end;
+
+		subreq = rctx->subreq;
+		subreq->rctx = rctx;
+		iv = iv_of_subreq(ctx, subreq);
+
+		atomic_inc(&rctx->req_pending);
+		bytes = geniv_iter_block(req, subreq, rctx, &segno, &done);
+
+		if (bytes == 0)
+			break;
+
+		cryptlen -= bytes;
+
+		if (ctx->iv_gen_ops)
+			ret = ctx->iv_gen_ops->generator(ctx, rctx, subreq, iv);
+
+		if (ret < 0) {
+			DMERR("Error in generating IV ret: %d\n", ret);
+			goto end;
+		}
+
+		skcipher_request_set_crypt(&subreq->req, &subreq->src,
+					   &subreq->dst, bytes, iv);
+
+		if (encrypt)
+			ret = crypto_skcipher_encrypt(&subreq->req);
+
+		else
+			ret = crypto_skcipher_decrypt(&subreq->req);
+
+		if (!ret && ctx->iv_gen_ops && ctx->iv_gen_ops->post)
+			ret = ctx->iv_gen_ops->post(ctx, rctx, subreq, iv);
+
+		switch (ret) {
+		/*
+		 * The request was queued by a crypto driver
+		 * but the driver request queue is full, let's wait.
+		 */
+		case -EBUSY:
+			wait_for_completion(&rctx->restart);
+			reinit_completion(&rctx->restart);
+			/* fall through */
+		/*
+		 * The request is queued and processed asynchronously,
+		 * completion function geniv_async_done() is called.
+		 */
+		case -EINPROGRESS:
+			/* Marking this NULL lets the creation of a new sub-
+			 * request when 'geniv_alloc_subreq' is called.
+			 */
+			rctx->subreq = NULL;
+			rctx->iv_sector++;
+			cond_resched();
+			break;
+		/*
+		 * The request was already processed (synchronously).
+		 */
+		case 0:
+			atomic_dec(&rctx->req_pending);
+			rctx->iv_sector++;
+			cond_resched();
+			continue;
+
+		/* There was an error while processing the request. */
+		default:
+			atomic_dec(&rctx->req_pending);
+			return ret;
+		}
+
+		if (ret)
+			break;
+	}
+
+	if (rctx->subreq && atomic_read(&rctx->req_pending) == 1) {
+		DMDEBUG("geniv:%s: Freeing sub request\n", str);
+		mempool_free(rctx->subreq, ctx->subreq_pool);
+	}
+
+end:
+	return ret;
+}
+
+static int geniv_encrypt(struct skcipher_request *req)
+{
+	return geniv_crypt(req, 1);
+}
+
+static int geniv_decrypt(struct skcipher_request *req)
+{
+	return geniv_crypt(req, 0);
+}
+
+static int geniv_init_tfm(struct crypto_skcipher *tfm)
+{
+	struct geniv_ctx *ctx = crypto_skcipher_ctx(tfm);
+	unsigned int reqsize, align;
+	size_t iv_size_padding;
+	char *algname, *chainmode;
+	int psize, ret = 0;
+
+	algname = (char *) crypto_tfm_alg_name(crypto_skcipher_tfm(tfm));
+	ctx->ciphermode = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
+	if (!ctx->ciphermode) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ctx->algname = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
+	if (!ctx->algname) {
+		ret = -ENOMEM;
+		goto free_ciphermode;
+	}
+
+	strlcpy(ctx->algname, algname, CRYPTO_MAX_ALG_NAME);
+	algname = ctx->algname;
+
+	/* Parse the algorithm name 'ivmode(chainmode(cipher))' */
+	ctx->ivmode	= strsep(&algname, "(");
+	chainmode	= strsep(&algname, "(");
+	ctx->cipher	= strsep(&algname, ")");
+
+	snprintf(ctx->ciphermode, CRYPTO_MAX_ALG_NAME, "%s(%s)",
+		 chainmode, ctx->cipher);
+
+	DMDEBUG("ciphermode=%s, ivmode=%s\n", ctx->ciphermode, ctx->ivmode);
+
+	/*
+	 * Usually the underlying cipher instances are spawned here, but since
+	 * the value of tfms_count (which is equal to the key_count) is not
+	 * known yet, create only one instance and delay the creation of the
+	 * rest of the instances of the underlying cipher 'cbc(aes)' until
+	 * the setkey operation is invoked.
+	 * The first instance created i.e. ctx->child will later be assigned as
+	 * the 1st element in the array ctx->tfms. Creation of atleast one
+	 * instance of the cipher is necessary to be created here to uncover
+	 * any errors earlier than during the setkey operation later where the
+	 * remaining instances are created.
+	 */
+	ctx->child = crypto_alloc_skcipher(ctx->ciphermode, 0, 0);
+	if (IS_ERR(ctx->child)) {
+		ret = PTR_ERR(ctx->child);
+		DMERR("Failed to create skcipher %s. err %d\n",
+		      ctx->ciphermode, ret);
+		goto free_algname;
+	}
+
+	/* Setup the current cipher's request structure */
+	align = crypto_skcipher_alignmask(tfm);
+	align &= ~(crypto_tfm_ctx_alignment() - 1);
+	reqsize = align + sizeof(struct geniv_req_ctx)
+			+ crypto_skcipher_reqsize(ctx->child);
+	crypto_skcipher_set_reqsize(tfm, reqsize);
+
+	ctx->iv_start = sizeof(struct geniv_subreq);
+	ctx->iv_start += crypto_skcipher_reqsize(tfm);
+
+	ctx->iv_size = crypto_skcipher_ivsize(tfm);
+	/* at least a 64 bit sector number should fit in our buffer */
+	if (ctx->iv_size)
+		ctx->iv_size = max(ctx->iv_size,
+				  (unsigned int)(sizeof(u64) / sizeof(u8)));
+
+	if (crypto_skcipher_alignmask(tfm) < CRYPTO_MINALIGN) {
+		/* Allocate the padding exactly */
+		iv_size_padding = -ctx->iv_start
+				& crypto_skcipher_alignmask(tfm);
+	} else {
+		/*
+		 * If the cipher requires greater alignment than kmalloc
+		 * alignment, we don't know the exact position of the
+		 * initialization vector. We must assume worst case.
+		 */
+		iv_size_padding = crypto_skcipher_alignmask(tfm);
+	}
+
+	/* create memory pool for sub-request structure */
+	psize = ctx->iv_start + iv_size_padding + ctx->iv_size;
+
+	ctx->subreq_pool = mempool_create_kmalloc_pool(MIN_IOS, psize);
+	if (!ctx->subreq_pool) {
+		ret = -ENOMEM;
+		DMERR("Could not allocate crypt sub-request mempool\n");
+		goto free_skcipher;
+	}
+out:
+	return ret;
+
+free_skcipher:
+	crypto_free_skcipher(ctx->child);
+free_algname:
+	kfree(ctx->algname);
+free_ciphermode:
+	kfree(ctx->ciphermode);
+	goto out;
+}
+
+static void geniv_exit_tfm(struct crypto_skcipher *tfm)
+{
+	struct geniv_ctx *ctx = crypto_skcipher_ctx(tfm);
+
+	if (ctx->iv_gen_ops && ctx->iv_gen_ops->dtr)
+		ctx->iv_gen_ops->dtr(ctx);
+
+	mempool_destroy(ctx->subreq_pool);
+	geniv_free_tfms(ctx);
+	kfree(ctx->ciphermode);
+	kfree(ctx->algname);
+}
+
+static void geniv_free(struct skcipher_instance *inst)
+{
+	struct crypto_skcipher_spawn *spawn = skcipher_instance_ctx(inst);
+
+	crypto_drop_skcipher(spawn);
+	kfree(inst);
+}
+
+static int geniv_create(struct crypto_template *tmpl,
+			struct rtattr **tb, char *algname)
+{
+	struct crypto_attr_type *algt;
+	struct skcipher_instance *inst;
+	struct skcipher_alg *alg;
+	struct crypto_skcipher_spawn *spawn;
+	const char *cipher_name;
+	int err;
+
+	algt = crypto_get_attr_type(tb);
+
+	if (IS_ERR(algt))
+		return PTR_ERR(algt);
+
+	if ((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask)
+		return -EINVAL;
+
+	cipher_name = crypto_attr_alg_name(tb[1]);
+
+	if (IS_ERR(cipher_name))
+		return PTR_ERR(cipher_name);
+
+	inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
+	if (!inst)
+		return -ENOMEM;
+
+	spawn = skcipher_instance_ctx(inst);
+
+	crypto_set_skcipher_spawn(spawn, skcipher_crypto_instance(inst));
+	err = crypto_grab_skcipher(spawn, cipher_name, 0,
+				    crypto_requires_sync(algt->type,
+							 algt->mask));
+
+	if (err)
+		goto err_free_inst;
+
+	alg = crypto_spawn_skcipher_alg(spawn);
+
+	err = -EINVAL;
+
+	/* Only support blocks of size which is of a power of 2 */
+	if (!is_power_of_2(alg->base.cra_blocksize))
+		goto err_drop_spawn;
+
+	/* algname: essiv, base.cra_name: cbc(aes) */
+	err = -ENAMETOOLONG;
+	if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
+		     algname, alg->base.cra_name) >= CRYPTO_MAX_ALG_NAME)
+		goto err_drop_spawn;
+	if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
+		     "%s(%s)", algname, alg->base.cra_driver_name) >=
+	    CRYPTO_MAX_ALG_NAME)
+		goto err_drop_spawn;
+
+	inst->alg.base.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER;
+	inst->alg.base.cra_priority = alg->base.cra_priority;
+	inst->alg.base.cra_blocksize = alg->base.cra_blocksize;
+	inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
+	inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
+	inst->alg.ivsize = alg->base.cra_blocksize;
+	inst->alg.chunksize = crypto_skcipher_alg_chunksize(alg);
+	inst->alg.min_keysize = crypto_skcipher_alg_min_keysize(alg);
+	inst->alg.max_keysize = crypto_skcipher_alg_max_keysize(alg);
+
+	inst->alg.setkey = geniv_setkey;
+	inst->alg.encrypt = geniv_encrypt;
+	inst->alg.decrypt = geniv_decrypt;
+
+	inst->alg.base.cra_ctxsize = sizeof(struct geniv_ctx);
+
+	inst->alg.init = geniv_init_tfm;
+	inst->alg.exit = geniv_exit_tfm;
+
+	inst->free = geniv_free;
+
+	err = skcipher_register_instance(tmpl, inst);
+	if (err)
+		goto err_drop_spawn;
+
+out:
+	return err;
+
+err_drop_spawn:
+	crypto_drop_skcipher(spawn);
+err_free_inst:
+	kfree(inst);
+	goto out;
+}
+
+static int crypto_essiv_create(struct crypto_template *tmpl,
+			       struct rtattr **tb)
+{
+	return geniv_create(tmpl, tb, "essiv");
+}
+
+static struct crypto_template crypto_essiv_tmpl = {
+	.name   = "essiv",
+	.create = crypto_essiv_create,
+	.module = THIS_MODULE,
+};
+
+static int __init essiv_init(void)
+{
+	return crypto_register_template(&crypto_essiv_tmpl);
+}
+
+static void __exit essiv_exit(void)
+{
+	crypto_unregister_template(&crypto_essiv_tmpl);
+}
+
+module_init(essiv_init);
+module_exit(essiv_exit);
+
+MODULE_AUTHOR("Binoy Jayan <binoy.jayan@linaro.org>");
+MODULE_DESCRIPTION(DM_NAME " essiv implementation for cryptocell 712");
+MODULE_LICENSE("GPL");