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_skcipher *tfm,
  22                               const u8               *in_key,
  23                               unsigned int            key_len)
  24 {
  25         struct nx_crypto_ctx *nx_ctx = crypto_skcipher_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 skcipher_request *req,
  54                             int                      enc)
  55 {
  56         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  57         struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
  58         struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
  59         unsigned long irq_flags;
  60         unsigned int processed = 0, to_process;
  61         int rc;
  62
  63         spin_lock_irqsave(&nx_ctx->lock, irq_flags);
  64
  65         if (enc)
  66                 NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT;
  67         else
  68                 NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;
  69
  70         do {
  71                 to_process = req->cryptlen - processed;
  72
  73                 rc = nx_build_sg_lists(nx_ctx, req->iv, req->dst, req->src,
  74                                        &to_process, processed,
  75                                        csbcpb->cpb.aes_cbc.iv);
  76                 if (rc)
  77                         goto out;
  78
  79                 if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) {
  80                         rc = -EINVAL;
  81                         goto out;
  82                 }
  83
  84                 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
  85                                    req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
  86                 if (rc)
  87                         goto out;
  88
  89                 memcpy(req->iv, csbcpb->cpb.aes_cbc.cv, AES_BLOCK_SIZE);
  90                 atomic_inc(&(nx_ctx->stats->aes_ops));
  91                 atomic64_add(csbcpb->csb.processed_byte_count,
  92                              &(nx_ctx->stats->aes_bytes));
  93
  94                 processed += to_process;
  95         } while (processed < req->cryptlen);
  96 out:
  97         spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
  98         return rc;
  99 }
 100
 101 static int cbc_aes_nx_encrypt(struct skcipher_request *req)
 102 {
 103         return cbc_aes_nx_crypt(req, 1);
 104 }
 105
 106 static int cbc_aes_nx_decrypt(struct skcipher_request *req)
 107 {
 108         return cbc_aes_nx_crypt(req, 0);
 109 }
 110
 111 struct skcipher_alg nx_cbc_aes_alg = {
 112         .base.cra_name          = "cbc(aes)",
 113         .base.cra_driver_name   = "cbc-aes-nx",
 114         .base.cra_priority      = 300,
 115         .base.cra_blocksize     = AES_BLOCK_SIZE,
 116         .base.cra_ctxsize       = sizeof(struct nx_crypto_ctx),
 117         .base.cra_alignmask     = 0xf,
 118         .base.cra_module        = THIS_MODULE,
 119         .init                   = nx_crypto_ctx_aes_cbc_init,
 120         .exit                   = nx_crypto_ctx_skcipher_exit,
 121         .min_keysize            = AES_MIN_KEY_SIZE,
 122         .max_keysize            = AES_MAX_KEY_SIZE,
 123         .ivsize                 = AES_BLOCK_SIZE,
 124         .setkey                 = cbc_aes_nx_set_key,
 125         .encrypt                = cbc_aes_nx_encrypt,
 126         .decrypt                = cbc_aes_nx_decrypt,
 127 };