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

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /**
   3  * AES CBC routines supporting the Power 7+ Nest Accelerators driver
   4  *
   5  * Copyright (C) 2011-2012 International Business Machines Inc.
   6  *
   7  * Author: Kent Yoder <yoder1@us.ibm.com>
   8  */
   9
  10 #include <crypto/aes.h>
  11 #include <crypto/algapi.h>
  12 #include <linux/module.h>
  13 #include <linux/types.h>
  14 #include <linux/crypto.h>
  15 #include <asm/vio.h>
  16
  17 #include "nx_csbcpb.h"
  18 #include "nx.h"
  19
  20
  21 static int cbc_aes_nx_set_key(struct crypto_tfm *tfm,
  22                               const u8          *in_key,
  23                               unsigned int       key_len)
  24 {
  25         struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm);
  26         struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
  27
  28         nx_ctx_init(nx_ctx, HCOP_FC_AES);
  29
  30         switch (key_len) {
  31         case AES_KEYSIZE_128:
  32                 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128);
  33                 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128];
  34                 break;
  35         case AES_KEYSIZE_192:
  36                 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_192);
  37                 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_192];
  38                 break;
  39         case AES_KEYSIZE_256:
  40                 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_256);
  41                 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_256];
  42                 break;
  43         default:
  44                 return -EINVAL;
  45         }
  46
  47         csbcpb->cpb.hdr.mode = NX_MODE_AES_CBC;
  48         memcpy(csbcpb->cpb.aes_cbc.key, in_key, key_len);
  49
  50         return 0;
  51 }
  52
  53 static int cbc_aes_nx_crypt(struct blkcipher_desc *desc,
  54                             struct scatterlist    *dst,
  55                             struct scatterlist    *src,
  56                             unsigned int           nbytes,
  57                             int                    enc)
  58 {
  59         struct nx_crypto_ctx *nx_ctx = crypto_blkcipher_ctx(desc->tfm);
  60         struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
  61         unsigned long irq_flags;
  62         unsigned int processed = 0, to_process;
  63         int rc;
  64
  65         spin_lock_irqsave(&nx_ctx->lock, irq_flags);
  66
  67         if (enc)
  68                 NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT;
  69         else
  70                 NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;
  71
  72         do {
  73                 to_process = nbytes - processed;
  74
  75                 rc = nx_build_sg_lists(nx_ctx, desc, dst, src, &to_process,
  76                                        processed, csbcpb->cpb.aes_cbc.iv);
  77                 if (rc)
  78                         goto out;
  79
  80                 if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) {
  81                         rc = -EINVAL;
  82                         goto out;
  83                 }
  84
  85                 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
  86                                    desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP);
  87                 if (rc)
  88                         goto out;
  89
  90                 memcpy(desc->info, csbcpb->cpb.aes_cbc.cv, AES_BLOCK_SIZE);
  91                 atomic_inc(&(nx_ctx->stats->aes_ops));
  92                 atomic64_add(csbcpb->csb.processed_byte_count,
  93                              &(nx_ctx->stats->aes_bytes));
  94
  95                 processed += to_process;
  96         } while (processed < nbytes);
  97 out:
  98         spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
  99         return rc;
 100 }
 101
 102 static int cbc_aes_nx_encrypt(struct blkcipher_desc *desc,
 103                               struct scatterlist    *dst,
 104                               struct scatterlist    *src,
 105                               unsigned int           nbytes)
 106 {
 107         return cbc_aes_nx_crypt(desc, dst, src, nbytes, 1);
 108 }
 109
 110 static int cbc_aes_nx_decrypt(struct blkcipher_desc *desc,
 111                               struct scatterlist    *dst,
 112                               struct scatterlist    *src,
 113                               unsigned int           nbytes)
 114 {
 115         return cbc_aes_nx_crypt(desc, dst, src, nbytes, 0);
 116 }
 117
 118 struct crypto_alg nx_cbc_aes_alg = {
 119         .cra_name        = "cbc(aes)",
 120         .cra_driver_name = "cbc-aes-nx",
 121         .cra_priority    = 300,
 122         .cra_flags       = CRYPTO_ALG_TYPE_BLKCIPHER,
 123         .cra_blocksize   = AES_BLOCK_SIZE,
 124         .cra_ctxsize     = sizeof(struct nx_crypto_ctx),
 125         .cra_type        = &crypto_blkcipher_type,
 126         .cra_alignmask   = 0xf,
 127         .cra_module      = THIS_MODULE,
 128         .cra_init        = nx_crypto_ctx_aes_cbc_init,
 129         .cra_exit        = nx_crypto_ctx_exit,
 130         .cra_blkcipher = {
 131                 .min_keysize = AES_MIN_KEY_SIZE,
 132                 .max_keysize = AES_MAX_KEY_SIZE,
 133                 .ivsize      = AES_BLOCK_SIZE,
 134                 .setkey      = cbc_aes_nx_set_key,
 135                 .encrypt     = cbc_aes_nx_encrypt,
 136                 .decrypt     = cbc_aes_nx_decrypt,
 137         }
 138 };