LXR linux/drivers/crypto/nx/nx-aes-cbc.c

   1/**
   2 * AES CBC routines supporting the Power 7+ Nest Accelerators driver
   3 *
   4 * Copyright (C) 2011-2012 International Business Machines Inc.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; version 2 only.
   9 *
  10 * This program is distributed in the hope that it will be useful,
  11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 * GNU General Public License for more details.
  14 *
  15 * You should have received a copy of the GNU General Public License
  16 * along with this program; if not, write to the Free Software
  17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18 *
  19 * Author: Kent Yoder <yoder1@us.ibm.com>
  20 */
  21
  22#include <crypto/aes.h>
  23#include <crypto/algapi.h>
  24#include <linux/module.h>
  25#include <linux/types.h>
  26#include <linux/crypto.h>
  27#include <asm/vio.h>
  28
  29#include "nx_csbcpb.h"
  30#include "nx.h"
  31
  32
  33static int cbc_aes_nx_set_key(struct crypto_tfm *tfm,
  34                              const u8          *in_key,
  35                              unsigned int       key_len)
  36{
  37        struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm);
  38        struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
  39
  40        nx_ctx_init(nx_ctx, HCOP_FC_AES);
  41
  42        switch (key_len) {
  43        case AES_KEYSIZE_128:
  44                NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128);
  45                nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128];
  46                break;
  47        case AES_KEYSIZE_192:
  48                NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_192);
  49                nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_192];
  50                break;
  51        case AES_KEYSIZE_256:
  52                NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_256);
  53                nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_256];
  54                break;
  55        default:
  56                return -EINVAL;
  57        }
  58
  59        csbcpb->cpb.hdr.mode = NX_MODE_AES_CBC;
  60        memcpy(csbcpb->cpb.aes_cbc.key, in_key, key_len);
  61
  62        return 0;
  63}
  64
  65static int cbc_aes_nx_crypt(struct blkcipher_desc *desc,
  66                            struct scatterlist    *dst,
  67                            struct scatterlist    *src,
  68                            unsigned int           nbytes,
  69                            int                    enc)
  70{
  71        struct nx_crypto_ctx *nx_ctx = crypto_blkcipher_ctx(desc->tfm);
  72        struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
  73        int rc;
  74
  75        if (nbytes > nx_ctx->ap->databytelen)
  76                return -EINVAL;
  77
  78        if (enc)
  79                NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT;
  80        else
  81                NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;
  82
  83        rc = nx_build_sg_lists(nx_ctx, desc, dst, src, nbytes,
  84                               csbcpb->cpb.aes_cbc.iv);
  85        if (rc)
  86                goto out;
  87
  88        if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) {
  89                rc = -EINVAL;
  90                goto out;
  91        }
  92
  93        rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
  94                           desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP);
  95        if (rc)
  96                goto out;
  97
  98        atomic_inc(&(nx_ctx->stats->aes_ops));
  99        atomic64_add(csbcpb->csb.processed_byte_count,
 100                     &(nx_ctx->stats->aes_bytes));
 101out:
 102        return rc;
 103}
 104
 105static int cbc_aes_nx_encrypt(struct blkcipher_desc *desc,
 106                              struct scatterlist    *dst,
 107                              struct scatterlist    *src,
 108                              unsigned int           nbytes)
 109{
 110        return cbc_aes_nx_crypt(desc, dst, src, nbytes, 1);
 111}
 112
 113static int cbc_aes_nx_decrypt(struct blkcipher_desc *desc,
 114                              struct scatterlist    *dst,
 115                              struct scatterlist    *src,
 116                              unsigned int           nbytes)
 117{
 118        return cbc_aes_nx_crypt(desc, dst, src, nbytes, 0);
 119}
 120
 121struct crypto_alg nx_cbc_aes_alg = {
 122        .cra_name        = "cbc(aes)",
 123        .cra_driver_name = "cbc-aes-nx",
 124        .cra_priority    = 300,
 125        .cra_flags       = CRYPTO_ALG_TYPE_BLKCIPHER,
 126        .cra_blocksize   = AES_BLOCK_SIZE,
 127        .cra_ctxsize     = sizeof(struct nx_crypto_ctx),
 128        .cra_type        = &crypto_blkcipher_type,
 129        .cra_alignmask   = 0xf,
 130        .cra_module      = THIS_MODULE,
 131        .cra_init        = nx_crypto_ctx_aes_cbc_init,
 132        .cra_exit        = nx_crypto_ctx_exit,
 133        .cra_blkcipher = {
 134                .min_keysize = AES_MIN_KEY_SIZE,
 135                .max_keysize = AES_MAX_KEY_SIZE,
 136                .ivsize      = AES_BLOCK_SIZE,
 137                .setkey      = cbc_aes_nx_set_key,
 138                .encrypt     = cbc_aes_nx_encrypt,
 139                .decrypt     = cbc_aes_nx_decrypt,
 140        }
 141};
 142