linux-stable/drivers/crypto/nx/nx-aes-cbc.c
Marcelo Cerri 2d290f0240 crypto: nx - fix limits to sg lists for AES-CBC
This patch updates the nx-aes-cbc implementation to perform several
hyper calls if needed in order to always respect the length limits for
scatter/gather lists.

Two different limits are considered:

 - "ibm,max-sg-len": maximum number of bytes of each scatter/gather
   list.

 - "ibm,max-sync-cop":
    - The total number of bytes that a scatter/gather list can hold.
    - The maximum number of elements that a scatter/gather list can have.

Reviewed-by: Joy Latten <jmlatten@linux.vnet.ibm.com>
Signed-off-by: Marcelo Cerri <mhcerri@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-09-02 20:32:53 +10:00

158 lines
4.4 KiB
C

/**
* AES CBC routines supporting the Power 7+ Nest Accelerators driver
*
* Copyright (C) 2011-2012 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/aes.h>
#include <crypto/algapi.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 cbc_aes_nx_set_key(struct crypto_tfm *tfm,
const u8 *in_key,
unsigned int key_len)
{
struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm);
struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
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_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128];
break;
case AES_KEYSIZE_192:
NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_192);
nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_192];
break;
case AES_KEYSIZE_256:
NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_256);
nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_256];
break;
default:
return -EINVAL;
}
csbcpb->cpb.hdr.mode = NX_MODE_AES_CBC;
memcpy(csbcpb->cpb.aes_cbc.key, in_key, key_len);
return 0;
}
static int cbc_aes_nx_crypt(struct blkcipher_desc *desc,
struct scatterlist *dst,
struct scatterlist *src,
unsigned int nbytes,
int enc)
{
struct nx_crypto_ctx *nx_ctx = crypto_blkcipher_ctx(desc->tfm);
struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
unsigned long irq_flags;
unsigned int processed = 0, to_process;
u32 max_sg_len;
int rc;
spin_lock_irqsave(&nx_ctx->lock, irq_flags);
max_sg_len = min_t(u32, nx_driver.of.max_sg_len/sizeof(struct nx_sg),
nx_ctx->ap->sglen);
if (enc)
NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT;
else
NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;
do {
to_process = min_t(u64, nbytes - processed,
nx_ctx->ap->databytelen);
to_process = min_t(u64, to_process,
NX_PAGE_SIZE * (max_sg_len - 1));
to_process = to_process & ~(AES_BLOCK_SIZE - 1);
rc = nx_build_sg_lists(nx_ctx, desc, dst, src, to_process,
processed, csbcpb->cpb.aes_cbc.iv);
if (rc)
goto out;
if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) {
rc = -EINVAL;
goto out;
}
rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP);
if (rc)
goto out;
memcpy(desc->info, csbcpb->cpb.aes_cbc.cv, AES_BLOCK_SIZE);
atomic_inc(&(nx_ctx->stats->aes_ops));
atomic64_add(csbcpb->csb.processed_byte_count,
&(nx_ctx->stats->aes_bytes));
processed += to_process;
} while (processed < nbytes);
out:
spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
return rc;
}
static int cbc_aes_nx_encrypt(struct blkcipher_desc *desc,
struct scatterlist *dst,
struct scatterlist *src,
unsigned int nbytes)
{
return cbc_aes_nx_crypt(desc, dst, src, nbytes, 1);
}
static int cbc_aes_nx_decrypt(struct blkcipher_desc *desc,
struct scatterlist *dst,
struct scatterlist *src,
unsigned int nbytes)
{
return cbc_aes_nx_crypt(desc, dst, src, nbytes, 0);
}
struct crypto_alg nx_cbc_aes_alg = {
.cra_name = "cbc(aes)",
.cra_driver_name = "cbc-aes-nx",
.cra_priority = 300,
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct nx_crypto_ctx),
.cra_type = &crypto_blkcipher_type,
.cra_alignmask = 0xf,
.cra_module = THIS_MODULE,
.cra_init = nx_crypto_ctx_aes_cbc_init,
.cra_exit = nx_crypto_ctx_exit,
.cra_blkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = cbc_aes_nx_set_key,
.encrypt = cbc_aes_nx_encrypt,
.decrypt = cbc_aes_nx_decrypt,
}
};