drivers/crypto/nx/nx-aes-ccm.c - maze/linux - Git at Google

 /**
  * AES CCM routines supporting the Power 7+ Nest Accelerators driver
  *
  * Copyright (C) 2012 International Business Machines Inc.
  *
  * 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; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  *
  * Author: Kent Yoder <yoder1@us.ibm.com>
  */

 #include <crypto/internal/aead.h>
 #include <crypto/aes.h>
 #include <crypto/algapi.h>
 #include <crypto/scatterwalk.h>
 #include <linux/module.h>
 #include <linux/types.h>
 #include <linux/crypto.h>
 #include <asm/vio.h>

 #include "nx_csbcpb.h"
 #include "nx.h"


 static int ccm_aes_nx_set_key(struct crypto_aead *tfm,
 			      const u8           *in_key,
 			      unsigned int        key_len)
 {
 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&tfm->base);
 	struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
 	struct nx_csbcpb *csbcpb_aead = nx_ctx->csbcpb_aead;

 	nx_ctx_init(nx_ctx, HCOP_FC_AES);

 	switch (key_len) {
 	case AES_KEYSIZE_128:
 		NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128);
 		NX_CPB_SET_KEY_SIZE(csbcpb_aead, NX_KS_AES_128);
 		nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128];
 		break;
 	default:
 		return -EINVAL;
 	}

 	csbcpb->cpb.hdr.mode = NX_MODE_AES_CCM;
 	memcpy(csbcpb->cpb.aes_ccm.key, in_key, key_len);

 	csbcpb_aead->cpb.hdr.mode = NX_MODE_AES_CCA;
 	memcpy(csbcpb_aead->cpb.aes_cca.key, in_key, key_len);

 	return 0;

 }

 static int ccm4309_aes_nx_set_key(struct crypto_aead *tfm,
 				  const u8           *in_key,
 				  unsigned int        key_len)
 {
 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&tfm->base);

 	if (key_len < 3)
 		return -EINVAL;

 	key_len -= 3;

 	memcpy(nx_ctx->priv.ccm.nonce, in_key + key_len, 3);

 	return ccm_aes_nx_set_key(tfm, in_key, key_len);
 }

 static int ccm_aes_nx_setauthsize(struct crypto_aead *tfm,
 				  unsigned int authsize)
 {
 	switch (authsize) {
 	case 4:
 	case 6:
 	case 8:
 	case 10:
 	case 12:
 	case 14:
 	case 16:
 		break;
 	default:
 		return -EINVAL;
 	}

 	crypto_aead_crt(tfm)->authsize = authsize;

 	return 0;
 }

 static int ccm4309_aes_nx_setauthsize(struct crypto_aead *tfm,
 				      unsigned int authsize)
 {
 	switch (authsize) {
 	case 8:
 	case 12:
 	case 16:
 		break;
 	default:
 		return -EINVAL;
 	}

 	crypto_aead_crt(tfm)->authsize = authsize;

 	return 0;
 }

 /* taken from crypto/ccm.c */
 static int set_msg_len(u8 *block, unsigned int msglen, int csize)
 {
 	__be32 data;

 	memset(block, 0, csize);
 	block += csize;

 	if (csize >= 4)
 		csize = 4;
 	else if (msglen > (unsigned int)(1 << (8 * csize)))
 		return -EOVERFLOW;

 	data = cpu_to_be32(msglen);
 	memcpy(block - csize, (u8 *)&data + 4 - csize, csize);

 	return 0;
 }

 /* taken from crypto/ccm.c */
 static inline int crypto_ccm_check_iv(const u8 *iv)
 {
 	/* 2 <= L <= 8, so 1 <= L' <= 7. */
 	if (1 > iv[0] || iv[0] > 7)
 		return -EINVAL;

 	return 0;
 }

 /* based on code from crypto/ccm.c */
 static int generate_b0(u8 *iv, unsigned int assoclen, unsigned int authsize,
 		       unsigned int cryptlen, u8 *b0)
 {
 	unsigned int l, lp, m = authsize;
 	int rc;

 	memcpy(b0, iv, 16);

 	lp = b0[0];
 	l = lp + 1;

 	/* set m, bits 3-5 */
 	*b0 |= (8 * ((m - 2) / 2));

 	/* set adata, bit 6, if associated data is used */
 	if (assoclen)
 		*b0 |= 64;

 	rc = set_msg_len(b0 + 16 - l, cryptlen, l);

 	return rc;
 }

 static int generate_pat(u8                   *iv,
 			struct aead_request  *req,
 			struct nx_crypto_ctx *nx_ctx,
 			unsigned int          authsize,
 			unsigned int          nbytes,
 			u8                   *out)
 {
 	struct nx_sg *nx_insg = nx_ctx->in_sg;
 	struct nx_sg *nx_outsg = nx_ctx->out_sg;
 	unsigned int iauth_len = 0;
 	struct vio_pfo_op *op = NULL;
 	u8 tmp[16], *b1 = NULL, *b0 = NULL, *result = NULL;
 	int rc;

 	/* zero the ctr value */
 	memset(iv + 15 - iv[0], 0, iv[0] + 1);

 	if (!req->assoclen) {
 		b0 = nx_ctx->csbcpb->cpb.aes_ccm.in_pat_or_b0;
 	} else if (req->assoclen <= 14) {
 		/* if associated data is 14 bytes or less, we do 1 GCM
 		 * operation on 2 AES blocks, B0 (stored in the csbcpb) and B1,
 		 * which is fed in through the source buffers here */
 		b0 = nx_ctx->csbcpb->cpb.aes_ccm.in_pat_or_b0;
 		b1 = nx_ctx->priv.ccm.iauth_tag;
 		iauth_len = req->assoclen;

 		nx_insg = nx_build_sg_list(nx_insg, b1, 16, nx_ctx->ap->sglen);
 		nx_outsg = nx_build_sg_list(nx_outsg, tmp, 16,
 					    nx_ctx->ap->sglen);

 		/* inlen should be negative, indicating to phyp that its a
 		 * pointer to an sg list */
 		nx_ctx->op.inlen = (nx_ctx->in_sg - nx_insg) *
 					sizeof(struct nx_sg);
 		nx_ctx->op.outlen = (nx_ctx->out_sg - nx_outsg) *
 					sizeof(struct nx_sg);

 		NX_CPB_FDM(nx_ctx->csbcpb) |= NX_FDM_ENDE_ENCRYPT;
 		NX_CPB_FDM(nx_ctx->csbcpb) |= NX_FDM_INTERMEDIATE;

 		op = &nx_ctx->op;
 		result = nx_ctx->csbcpb->cpb.aes_ccm.out_pat_or_mac;
 	} else if (req->assoclen <= 65280) {
 		/* if associated data is less than (2^16 - 2^8), we construct
 		 * B1 differently and feed in the associated data to a CCA
 		 * operation */
 		b0 = nx_ctx->csbcpb_aead->cpb.aes_cca.b0;
 		b1 = nx_ctx->csbcpb_aead->cpb.aes_cca.b1;
 		iauth_len = 14;

 		/* remaining assoc data must have scatterlist built for it */
 		nx_insg = nx_walk_and_build(nx_insg, nx_ctx->ap->sglen,
 					    req->assoc, iauth_len,
 					    req->assoclen - iauth_len);
 		nx_ctx->op_aead.inlen = (nx_ctx->in_sg - nx_insg) *
 						sizeof(struct nx_sg);

 		op = &nx_ctx->op_aead;
 		result = nx_ctx->csbcpb_aead->cpb.aes_cca.out_pat_or_b0;
 	} else {
 		/* if associated data is less than (2^32), we construct B1
 		 * differently yet again and feed in the associated data to a
 		 * CCA operation */
 		pr_err("associated data len is %u bytes (returning -EINVAL)\n",
 		       req->assoclen);
 		rc = -EINVAL;
 	}

 	rc = generate_b0(iv, req->assoclen, authsize, nbytes, b0);
 	if (rc)
 		goto done;

 	if (b1) {
 		memset(b1, 0, 16);
 		*(u16 *)b1 = (u16)req->assoclen;

 		scatterwalk_map_and_copy(b1 + 2, req->assoc, 0,
 					 iauth_len, SCATTERWALK_FROM_SG);

 		rc = nx_hcall_sync(nx_ctx, op,
 				   req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
 		if (rc)
 			goto done;

 		atomic_inc(&(nx_ctx->stats->aes_ops));
 		atomic64_add(req->assoclen, &(nx_ctx->stats->aes_bytes));

 		memcpy(out, result, AES_BLOCK_SIZE);
 	}
 done:
 	return rc;
 }

 static int ccm_nx_decrypt(struct aead_request   *req,
 			  struct blkcipher_desc *desc)
 {
 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
 	struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
 	unsigned int nbytes = req->cryptlen;
 	unsigned int authsize = crypto_aead_authsize(crypto_aead_reqtfm(req));
 	struct nx_ccm_priv *priv = &nx_ctx->priv.ccm;
 	int rc = -1;

 	if (nbytes > nx_ctx->ap->databytelen)
 		return -EINVAL;

 	nbytes -= authsize;

 	/* copy out the auth tag to compare with later */
 	scatterwalk_map_and_copy(priv->oauth_tag,
 				 req->src, nbytes, authsize,
 				 SCATTERWALK_FROM_SG);

 	rc = generate_pat(desc->info, req, nx_ctx, authsize, nbytes,
 			  csbcpb->cpb.aes_ccm.in_pat_or_b0);
 	if (rc)
 		goto out;

 	rc = nx_build_sg_lists(nx_ctx, desc, req->dst, req->src, nbytes,
 			       csbcpb->cpb.aes_ccm.iv_or_ctr);
 	if (rc)
 		goto out;

 	NX_CPB_FDM(nx_ctx->csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;
 	NX_CPB_FDM(nx_ctx->csbcpb) &= ~NX_FDM_INTERMEDIATE;

 	rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
 			   req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
 	if (rc)
 		goto out;

 	atomic_inc(&(nx_ctx->stats->aes_ops));
 	atomic64_add(csbcpb->csb.processed_byte_count,
 		     &(nx_ctx->stats->aes_bytes));

 	rc = memcmp(csbcpb->cpb.aes_ccm.out_pat_or_mac, priv->oauth_tag,
 		    authsize) ? -EBADMSG : 0;
 out:
 	return rc;
 }

 static int ccm_nx_encrypt(struct aead_request   *req,
 			  struct blkcipher_desc *desc)
 {
 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
 	struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
 	unsigned int nbytes = req->cryptlen;
 	unsigned int authsize = crypto_aead_authsize(crypto_aead_reqtfm(req));
 	int rc = -1;

 	if (nbytes > nx_ctx->ap->databytelen)
 		return -EINVAL;

 	rc = generate_pat(desc->info, req, nx_ctx, authsize, nbytes,
 			  csbcpb->cpb.aes_ccm.in_pat_or_b0);
 	if (rc)
 		goto out;

 	rc = nx_build_sg_lists(nx_ctx, desc, req->dst, req->src, nbytes,
 			       csbcpb->cpb.aes_ccm.iv_or_ctr);
 	if (rc)
 		goto out;

 	NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT;
 	NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;

 	rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
 			   req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
 	if (rc)
 		goto out;

 	atomic_inc(&(nx_ctx->stats->aes_ops));
 	atomic64_add(csbcpb->csb.processed_byte_count,
 		     &(nx_ctx->stats->aes_bytes));

 	/* copy out the auth tag */
 	scatterwalk_map_and_copy(csbcpb->cpb.aes_ccm.out_pat_or_mac,
 				 req->dst, nbytes, authsize,
 				 SCATTERWALK_TO_SG);
 out:
 	return rc;
 }

 static int ccm4309_aes_nx_encrypt(struct aead_request *req)
 {
 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
 	struct blkcipher_desc desc;
 	u8 *iv = nx_ctx->priv.ccm.iv;

 	iv[0] = 3;
 	memcpy(iv + 1, nx_ctx->priv.ccm.nonce, 3);
 	memcpy(iv + 4, req->iv, 8);

 	desc.info = iv;
 	desc.tfm = (struct crypto_blkcipher *)req->base.tfm;

 	return ccm_nx_encrypt(req, &desc);
 }

 static int ccm_aes_nx_encrypt(struct aead_request *req)
 {
 	struct blkcipher_desc desc;
 	int rc;

 	desc.info = req->iv;
 	desc.tfm = (struct crypto_blkcipher *)req->base.tfm;

 	rc = crypto_ccm_check_iv(desc.info);
 	if (rc)
 		return rc;

 	return ccm_nx_encrypt(req, &desc);
 }

 static int ccm4309_aes_nx_decrypt(struct aead_request *req)
 {
 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
 	struct blkcipher_desc desc;
 	u8 *iv = nx_ctx->priv.ccm.iv;

 	iv[0] = 3;
 	memcpy(iv + 1, nx_ctx->priv.ccm.nonce, 3);
 	memcpy(iv + 4, req->iv, 8);

 	desc.info = iv;
 	desc.tfm = (struct crypto_blkcipher *)req->base.tfm;

 	return ccm_nx_decrypt(req, &desc);
 }

 static int ccm_aes_nx_decrypt(struct aead_request *req)
 {
 	struct blkcipher_desc desc;
 	int rc;

 	desc.info = req->iv;
 	desc.tfm = (struct crypto_blkcipher *)req->base.tfm;

 	rc = crypto_ccm_check_iv(desc.info);
 	if (rc)
 		return rc;

 	return ccm_nx_decrypt(req, &desc);
 }

 /* tell the block cipher walk routines that this is a stream cipher by
  * setting cra_blocksize to 1. Even using blkcipher_walk_virt_block
  * during encrypt/decrypt doesn't solve this problem, because it calls
  * blkcipher_walk_done under the covers, which doesn't use walk->blocksize,
  * but instead uses this tfm->blocksize. */
 struct crypto_alg nx_ccm_aes_alg = {
 	.cra_name        = "ccm(aes)",
 	.cra_driver_name = "ccm-aes-nx",
 	.cra_priority    = 300,
 	.cra_flags       = CRYPTO_ALG_TYPE_AEAD |
 			   CRYPTO_ALG_NEED_FALLBACK,
 	.cra_blocksize   = 1,
 	.cra_ctxsize     = sizeof(struct nx_crypto_ctx),
 	.cra_type        = &crypto_aead_type,
 	.cra_module      = THIS_MODULE,
 	.cra_list        = LIST_HEAD_INIT(nx_ccm_aes_alg.cra_list),
 	.cra_init        = nx_crypto_ctx_aes_ccm_init,
 	.cra_exit        = nx_crypto_ctx_exit,
 	.cra_aead = {
 		.ivsize      = AES_BLOCK_SIZE,
 		.maxauthsize = AES_BLOCK_SIZE,
 		.setkey      = ccm_aes_nx_set_key,
 		.setauthsize = ccm_aes_nx_setauthsize,
 		.encrypt     = ccm_aes_nx_encrypt,
 		.decrypt     = ccm_aes_nx_decrypt,
 	}
 };

 struct crypto_alg nx_ccm4309_aes_alg = {
 	.cra_name        = "rfc4309(ccm(aes))",
 	.cra_driver_name = "rfc4309-ccm-aes-nx",
 	.cra_priority    = 300,
 	.cra_flags       = CRYPTO_ALG_TYPE_AEAD |
 			   CRYPTO_ALG_NEED_FALLBACK,
 	.cra_blocksize   = 1,
 	.cra_ctxsize     = sizeof(struct nx_crypto_ctx),
 	.cra_type        = &crypto_nivaead_type,
 	.cra_module      = THIS_MODULE,
 	.cra_list        = LIST_HEAD_INIT(nx_ccm4309_aes_alg.cra_list),
 	.cra_init        = nx_crypto_ctx_aes_ccm_init,
 	.cra_exit        = nx_crypto_ctx_exit,
 	.cra_aead = {
 		.ivsize      = 8,
 		.maxauthsize = AES_BLOCK_SIZE,
 		.setkey      = ccm4309_aes_nx_set_key,
 		.setauthsize = ccm4309_aes_nx_setauthsize,
 		.encrypt     = ccm4309_aes_nx_encrypt,
 		.decrypt     = ccm4309_aes_nx_decrypt,
 		.geniv       = "seqiv",
 	}
 };
	/**
	* AES CCM routines supporting the Power 7+ Nest Accelerators driver
	*
	* Copyright (C) 2012 International Business Machines Inc.
	*
	* 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; version 2 only.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	*
	* Author: Kent Yoder <yoder1@us.ibm.com>
	*/

	#include <crypto/internal/aead.h>
	#include <crypto/aes.h>
	#include <crypto/algapi.h>
	#include <crypto/scatterwalk.h>
	#include <linux/module.h>
	#include <linux/types.h>
	#include <linux/crypto.h>
	#include <asm/vio.h>

	#include "nx_csbcpb.h"
	#include "nx.h"


	static int ccm_aes_nx_set_key(struct crypto_aead *tfm,
	const u8 *in_key,
	unsigned int key_len)
	{
	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&tfm->base);
	struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
	struct nx_csbcpb *csbcpb_aead = nx_ctx->csbcpb_aead;

	nx_ctx_init(nx_ctx, HCOP_FC_AES);

	switch (key_len) {
	case AES_KEYSIZE_128:
	NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128);
	NX_CPB_SET_KEY_SIZE(csbcpb_aead, NX_KS_AES_128);
	nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128];
	break;
	default:
	return -EINVAL;
	}

	csbcpb->cpb.hdr.mode = NX_MODE_AES_CCM;
	memcpy(csbcpb->cpb.aes_ccm.key, in_key, key_len);

	csbcpb_aead->cpb.hdr.mode = NX_MODE_AES_CCA;
	memcpy(csbcpb_aead->cpb.aes_cca.key, in_key, key_len);

	return 0;

	}

	static int ccm4309_aes_nx_set_key(struct crypto_aead *tfm,
	const u8 *in_key,
	unsigned int key_len)
	{
	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&tfm->base);

	if (key_len < 3)
	return -EINVAL;

	key_len -= 3;

	memcpy(nx_ctx->priv.ccm.nonce, in_key + key_len, 3);

	return ccm_aes_nx_set_key(tfm, in_key, key_len);
	}

	static int ccm_aes_nx_setauthsize(struct crypto_aead *tfm,
	unsigned int authsize)
	{
	switch (authsize) {
	case 4:
	case 6:
	case 8:
	case 10:
	case 12:
	case 14:
	case 16:
	break;
	default:
	return -EINVAL;
	}

	crypto_aead_crt(tfm)->authsize = authsize;

	return 0;
	}

	static int ccm4309_aes_nx_setauthsize(struct crypto_aead *tfm,
	unsigned int authsize)
	{
	switch (authsize) {
	case 8:
	case 12:
	case 16:
	break;
	default:
	return -EINVAL;
	}

	crypto_aead_crt(tfm)->authsize = authsize;

	return 0;
	}

	/* taken from crypto/ccm.c */
	static int set_msg_len(u8 *block, unsigned int msglen, int csize)
	{
	__be32 data;

	memset(block, 0, csize);
	block += csize;

	if (csize >= 4)
	csize = 4;
	else if (msglen > (unsigned int)(1 << (8 * csize)))
	return -EOVERFLOW;

	data = cpu_to_be32(msglen);
	memcpy(block - csize, (u8 *)&data + 4 - csize, csize);

	return 0;
	}

	/* taken from crypto/ccm.c */
	static inline int crypto_ccm_check_iv(const u8 *iv)
	{
	/* 2 <= L <= 8, so 1 <= L' <= 7. */
	if (1 > iv[0] \|\| iv[0] > 7)
	return -EINVAL;

	return 0;
	}

	/* based on code from crypto/ccm.c */
	static int generate_b0(u8 *iv, unsigned int assoclen, unsigned int authsize,
	unsigned int cryptlen, u8 *b0)
	{
	unsigned int l, lp, m = authsize;
	int rc;

	memcpy(b0, iv, 16);

	lp = b0[0];
	l = lp + 1;

	/* set m, bits 3-5 */
	b0 \|= (8 ((m - 2) / 2));

	/* set adata, bit 6, if associated data is used */
	if (assoclen)
	*b0 \|= 64;

	rc = set_msg_len(b0 + 16 - l, cryptlen, l);

	return rc;
	}

	static int generate_pat(u8 *iv,
	struct aead_request *req,
	struct nx_crypto_ctx *nx_ctx,
	unsigned int authsize,
	unsigned int nbytes,
	u8 *out)
	{
	struct nx_sg *nx_insg = nx_ctx->in_sg;
	struct nx_sg *nx_outsg = nx_ctx->out_sg;
	unsigned int iauth_len = 0;
	struct vio_pfo_op *op = NULL;
	u8 tmp[16], b1 = NULL, b0 = NULL, *result = NULL;
	int rc;

	/* zero the ctr value */
	memset(iv + 15 - iv[0], 0, iv[0] + 1);

	if (!req->assoclen) {
	b0 = nx_ctx->csbcpb->cpb.aes_ccm.in_pat_or_b0;
	} else if (req->assoclen <= 14) {
	/* if associated data is 14 bytes or less, we do 1 GCM
	* operation on 2 AES blocks, B0 (stored in the csbcpb) and B1,
	* which is fed in through the source buffers here */
	b0 = nx_ctx->csbcpb->cpb.aes_ccm.in_pat_or_b0;
	b1 = nx_ctx->priv.ccm.iauth_tag;
	iauth_len = req->assoclen;

	nx_insg = nx_build_sg_list(nx_insg, b1, 16, nx_ctx->ap->sglen);
	nx_outsg = nx_build_sg_list(nx_outsg, tmp, 16,
	nx_ctx->ap->sglen);

	/* inlen should be negative, indicating to phyp that its a
	* pointer to an sg list */
	nx_ctx->op.inlen = (nx_ctx->in_sg - nx_insg) *
	sizeof(struct nx_sg);
	nx_ctx->op.outlen = (nx_ctx->out_sg - nx_outsg) *
	sizeof(struct nx_sg);

	NX_CPB_FDM(nx_ctx->csbcpb) \|= NX_FDM_ENDE_ENCRYPT;
	NX_CPB_FDM(nx_ctx->csbcpb) \|= NX_FDM_INTERMEDIATE;

	op = &nx_ctx->op;
	result = nx_ctx->csbcpb->cpb.aes_ccm.out_pat_or_mac;
	} else if (req->assoclen <= 65280) {
	/* if associated data is less than (2^16 - 2^8), we construct
	* B1 differently and feed in the associated data to a CCA
	* operation */
	b0 = nx_ctx->csbcpb_aead->cpb.aes_cca.b0;
	b1 = nx_ctx->csbcpb_aead->cpb.aes_cca.b1;
	iauth_len = 14;

	/* remaining assoc data must have scatterlist built for it */
	nx_insg = nx_walk_and_build(nx_insg, nx_ctx->ap->sglen,
	req->assoc, iauth_len,
	req->assoclen - iauth_len);
	nx_ctx->op_aead.inlen = (nx_ctx->in_sg - nx_insg) *
	sizeof(struct nx_sg);

	op = &nx_ctx->op_aead;
	result = nx_ctx->csbcpb_aead->cpb.aes_cca.out_pat_or_b0;
	} else {
	/* if associated data is less than (2^32), we construct B1
	* differently yet again and feed in the associated data to a
	* CCA operation */
	pr_err("associated data len is %u bytes (returning -EINVAL)\n",
	req->assoclen);
	rc = -EINVAL;
	}

	rc = generate_b0(iv, req->assoclen, authsize, nbytes, b0);
	if (rc)
	goto done;

	if (b1) {
	memset(b1, 0, 16);
	(u16 )b1 = (u16)req->assoclen;

	scatterwalk_map_and_copy(b1 + 2, req->assoc, 0,
	iauth_len, SCATTERWALK_FROM_SG);

	rc = nx_hcall_sync(nx_ctx, op,
	req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
	if (rc)
	goto done;

	atomic_inc(&(nx_ctx->stats->aes_ops));
	atomic64_add(req->assoclen, &(nx_ctx->stats->aes_bytes));

	memcpy(out, result, AES_BLOCK_SIZE);
	}
	done:
	return rc;
	}

	static int ccm_nx_decrypt(struct aead_request *req,
	struct blkcipher_desc *desc)
	{
	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
	struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
	unsigned int nbytes = req->cryptlen;
	unsigned int authsize = crypto_aead_authsize(crypto_aead_reqtfm(req));
	struct nx_ccm_priv *priv = &nx_ctx->priv.ccm;
	int rc = -1;

	if (nbytes > nx_ctx->ap->databytelen)
	return -EINVAL;

	nbytes -= authsize;

	/* copy out the auth tag to compare with later */
	scatterwalk_map_and_copy(priv->oauth_tag,
	req->src, nbytes, authsize,
	SCATTERWALK_FROM_SG);

	rc = generate_pat(desc->info, req, nx_ctx, authsize, nbytes,
	csbcpb->cpb.aes_ccm.in_pat_or_b0);
	if (rc)
	goto out;

	rc = nx_build_sg_lists(nx_ctx, desc, req->dst, req->src, nbytes,
	csbcpb->cpb.aes_ccm.iv_or_ctr);
	if (rc)
	goto out;

	NX_CPB_FDM(nx_ctx->csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;
	NX_CPB_FDM(nx_ctx->csbcpb) &= ~NX_FDM_INTERMEDIATE;

	rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
	req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
	if (rc)
	goto out;

	atomic_inc(&(nx_ctx->stats->aes_ops));
	atomic64_add(csbcpb->csb.processed_byte_count,
	&(nx_ctx->stats->aes_bytes));

	rc = memcmp(csbcpb->cpb.aes_ccm.out_pat_or_mac, priv->oauth_tag,
	authsize) ? -EBADMSG : 0;
	out:
	return rc;
	}

	static int ccm_nx_encrypt(struct aead_request *req,
	struct blkcipher_desc *desc)
	{
	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
	struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
	unsigned int nbytes = req->cryptlen;
	unsigned int authsize = crypto_aead_authsize(crypto_aead_reqtfm(req));
	int rc = -1;

	if (nbytes > nx_ctx->ap->databytelen)
	return -EINVAL;

	rc = generate_pat(desc->info, req, nx_ctx, authsize, nbytes,
	csbcpb->cpb.aes_ccm.in_pat_or_b0);
	if (rc)
	goto out;

	rc = nx_build_sg_lists(nx_ctx, desc, req->dst, req->src, nbytes,
	csbcpb->cpb.aes_ccm.iv_or_ctr);
	if (rc)
	goto out;

	NX_CPB_FDM(csbcpb) \|= NX_FDM_ENDE_ENCRYPT;
	NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;

	rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
	req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
	if (rc)
	goto out;

	atomic_inc(&(nx_ctx->stats->aes_ops));
	atomic64_add(csbcpb->csb.processed_byte_count,
	&(nx_ctx->stats->aes_bytes));

	/* copy out the auth tag */
	scatterwalk_map_and_copy(csbcpb->cpb.aes_ccm.out_pat_or_mac,
	req->dst, nbytes, authsize,
	SCATTERWALK_TO_SG);
	out:
	return rc;
	}

	static int ccm4309_aes_nx_encrypt(struct aead_request *req)
	{
	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
	struct blkcipher_desc desc;
	u8 *iv = nx_ctx->priv.ccm.iv;

	iv[0] = 3;
	memcpy(iv + 1, nx_ctx->priv.ccm.nonce, 3);
	memcpy(iv + 4, req->iv, 8);

	desc.info = iv;
	desc.tfm = (struct crypto_blkcipher *)req->base.tfm;

	return ccm_nx_encrypt(req, &desc);
	}

	static int ccm_aes_nx_encrypt(struct aead_request *req)
	{
	struct blkcipher_desc desc;
	int rc;

	desc.info = req->iv;
	desc.tfm = (struct crypto_blkcipher *)req->base.tfm;

	rc = crypto_ccm_check_iv(desc.info);
	if (rc)
	return rc;

	return ccm_nx_encrypt(req, &desc);
	}

	static int ccm4309_aes_nx_decrypt(struct aead_request *req)
	{
	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
	struct blkcipher_desc desc;
	u8 *iv = nx_ctx->priv.ccm.iv;

	iv[0] = 3;
	memcpy(iv + 1, nx_ctx->priv.ccm.nonce, 3);
	memcpy(iv + 4, req->iv, 8);

	desc.info = iv;
	desc.tfm = (struct crypto_blkcipher *)req->base.tfm;

	return ccm_nx_decrypt(req, &desc);
	}

	static int ccm_aes_nx_decrypt(struct aead_request *req)
	{
	struct blkcipher_desc desc;
	int rc;

	desc.info = req->iv;
	desc.tfm = (struct crypto_blkcipher *)req->base.tfm;

	rc = crypto_ccm_check_iv(desc.info);
	if (rc)
	return rc;

	return ccm_nx_decrypt(req, &desc);
	}

	/* tell the block cipher walk routines that this is a stream cipher by
	* setting cra_blocksize to 1. Even using blkcipher_walk_virt_block
	* during encrypt/decrypt doesn't solve this problem, because it calls
	* blkcipher_walk_done under the covers, which doesn't use walk->blocksize,
	* but instead uses this tfm->blocksize. */
	struct crypto_alg nx_ccm_aes_alg = {
	.cra_name = "ccm(aes)",
	.cra_driver_name = "ccm-aes-nx",
	.cra_priority = 300,
	.cra_flags = CRYPTO_ALG_TYPE_AEAD \|
	CRYPTO_ALG_NEED_FALLBACK,
	.cra_blocksize = 1,
	.cra_ctxsize = sizeof(struct nx_crypto_ctx),
	.cra_type = &crypto_aead_type,
	.cra_module = THIS_MODULE,
	.cra_list = LIST_HEAD_INIT(nx_ccm_aes_alg.cra_list),
	.cra_init = nx_crypto_ctx_aes_ccm_init,
	.cra_exit = nx_crypto_ctx_exit,
	.cra_aead = {
	.ivsize = AES_BLOCK_SIZE,
	.maxauthsize = AES_BLOCK_SIZE,
	.setkey = ccm_aes_nx_set_key,
	.setauthsize = ccm_aes_nx_setauthsize,
	.encrypt = ccm_aes_nx_encrypt,
	.decrypt = ccm_aes_nx_decrypt,
	}
	};

	struct crypto_alg nx_ccm4309_aes_alg = {
	.cra_name = "rfc4309(ccm(aes))",
	.cra_driver_name = "rfc4309-ccm-aes-nx",
	.cra_priority = 300,
	.cra_flags = CRYPTO_ALG_TYPE_AEAD \|
	CRYPTO_ALG_NEED_FALLBACK,
	.cra_blocksize = 1,
	.cra_ctxsize = sizeof(struct nx_crypto_ctx),
	.cra_type = &crypto_nivaead_type,
	.cra_module = THIS_MODULE,
	.cra_list = LIST_HEAD_INIT(nx_ccm4309_aes_alg.cra_list),
	.cra_init = nx_crypto_ctx_aes_ccm_init,
	.cra_exit = nx_crypto_ctx_exit,
	.cra_aead = {
	.ivsize = 8,
	.maxauthsize = AES_BLOCK_SIZE,
	.setkey = ccm4309_aes_nx_set_key,
	.setauthsize = ccm4309_aes_nx_setauthsize,
	.encrypt = ccm4309_aes_nx_encrypt,
	.decrypt = ccm4309_aes_nx_decrypt,
	.geniv = "seqiv",
	}
	};