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

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /**
   3  * AES CTR 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/ctr.h>
  12 #include <crypto/algapi.h>
  13 #include <linux/module.h>
  14 #include <linux/types.h>
  15 #include <linux/crypto.h>
  16 #include <asm/vio.h>
  17
  18 #include "nx_csbcpb.h"
  19 #include "nx.h"
  20
  21
  22 static int ctr_aes_nx_set_key(struct crypto_skcipher *tfm,
  23                               const u8               *in_key,
  24                               unsigned int            key_len)
  25 {
  26         struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
  27         struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
  28
  29         nx_ctx_init(nx_ctx, HCOP_FC_AES);
  30
  31         switch (key_len) {
  32         case AES_KEYSIZE_128:
  33                 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128);
  34                 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128];
  35                 break;
  36         case AES_KEYSIZE_192:
  37                 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_192);
  38                 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_192];
  39                 break;
  40         case AES_KEYSIZE_256:
  41                 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_256);
  42                 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_256];
  43                 break;
  44         default:
  45                 return -EINVAL;
  46         }
  47
  48         csbcpb->cpb.hdr.mode = NX_MODE_AES_CTR;
  49         memcpy(csbcpb->cpb.aes_ctr.key, in_key, key_len);
  50
  51         return 0;
  52 }
  53
  54 static int ctr3686_aes_nx_set_key(struct crypto_skcipher *tfm,
  55                                   const u8               *in_key,
  56                                   unsigned int            key_len)
  57 {
  58         struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
  59
  60         if (key_len < CTR_RFC3686_NONCE_SIZE)
  61                 return -EINVAL;
  62
  63         memcpy(nx_ctx->priv.ctr.nonce,
  64                in_key + key_len - CTR_RFC3686_NONCE_SIZE,
  65                CTR_RFC3686_NONCE_SIZE);
  66
  67         key_len -= CTR_RFC3686_NONCE_SIZE;
  68
  69         return ctr_aes_nx_set_key(tfm, in_key, key_len);
  70 }
  71
  72 static int ctr_aes_nx_crypt(struct skcipher_request *req, u8 *iv)
  73 {
  74         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  75         struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
  76         struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
  77         unsigned long irq_flags;
  78         unsigned int processed = 0, to_process;
  79         int rc;
  80
  81         spin_lock_irqsave(&nx_ctx->lock, irq_flags);
  82
  83         do {
  84                 to_process = req->cryptlen - processed;
  85
  86                 rc = nx_build_sg_lists(nx_ctx, iv, req->dst, req->src,
  87                                        &to_process, processed,
  88                                        csbcpb->cpb.aes_ctr.iv);
  89                 if (rc)
  90                         goto out;
  91
  92                 if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) {
  93                         rc = -EINVAL;
  94                         goto out;
  95                 }
  96
  97                 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
  98                                    req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
  99                 if (rc)
 100                         goto out;
 101
 102                 memcpy(iv, csbcpb->cpb.aes_cbc.cv, AES_BLOCK_SIZE);
 103
 104                 atomic_inc(&(nx_ctx->stats->aes_ops));
 105                 atomic64_add(csbcpb->csb.processed_byte_count,
 106                              &(nx_ctx->stats->aes_bytes));
 107
 108                 processed += to_process;
 109         } while (processed < req->cryptlen);
 110 out:
 111         spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
 112         return rc;
 113 }
 114
 115 static int ctr3686_aes_nx_crypt(struct skcipher_request *req)
 116 {
 117         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 118         struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
 119         u8 iv[16];
 120
 121         memcpy(iv, nx_ctx->priv.ctr.nonce, CTR_RFC3686_IV_SIZE);
 122         memcpy(iv + CTR_RFC3686_NONCE_SIZE, req->iv, CTR_RFC3686_IV_SIZE);
 123         iv[12] = iv[13] = iv[14] = 0;
 124         iv[15] = 1;
 125
 126         return ctr_aes_nx_crypt(req, iv);
 127 }
 128
 129 struct skcipher_alg nx_ctr3686_aes_alg = {
 130         .base.cra_name          = "rfc3686(ctr(aes))",
 131         .base.cra_driver_name   = "rfc3686-ctr-aes-nx",
 132         .base.cra_priority      = 300,
 133         .base.cra_blocksize     = 1,
 134         .base.cra_ctxsize       = sizeof(struct nx_crypto_ctx),
 135         .base.cra_module        = THIS_MODULE,
 136         .init                   = nx_crypto_ctx_aes_ctr_init,
 137         .exit                   = nx_crypto_ctx_skcipher_exit,
 138         .min_keysize            = AES_MIN_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
 139         .max_keysize            = AES_MAX_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
 140         .ivsize                 = CTR_RFC3686_IV_SIZE,
 141         .setkey                 = ctr3686_aes_nx_set_key,
 142         .encrypt                = ctr3686_aes_nx_crypt,
 143         .decrypt                = ctr3686_aes_nx_crypt,
 144         .chunksize              = AES_BLOCK_SIZE,
 145 };