drivers/crypto/ccp/ccp-crypto-aes.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * AMD Cryptographic Coprocessor (CCP) AES crypto API support
   4  *
   5  * Copyright (C) 2013-2019 Advanced Micro Devices, Inc.
   6  *
   7  * Author: Tom Lendacky <thomas.lendacky@amd.com>
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/sched.h>
  12 #include <linux/delay.h>
  13 #include <linux/scatterlist.h>
  14 #include <linux/crypto.h>
  15 #include <crypto/algapi.h>
  16 #include <crypto/aes.h>
  17 #include <crypto/ctr.h>
  18 #include <crypto/scatterwalk.h>
  19
  20 #include "ccp-crypto.h"
  21
  22 static int ccp_aes_complete(struct crypto_async_request *async_req, int ret)
  23 {
  24         struct skcipher_request *req = skcipher_request_cast(async_req);
  25         struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(
  26                 crypto_skcipher_reqtfm(req));
  27         struct ccp_aes_req_ctx *rctx = skcipher_request_ctx_dma(req);
  28
  29         if (ret)
  30                 return ret;
  31
  32         if (ctx->u.aes.mode != CCP_AES_MODE_ECB)
  33                 memcpy(req->iv, rctx->iv, AES_BLOCK_SIZE);
  34
  35         return 0;
  36 }
  37
  38 static int ccp_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
  39                           unsigned int key_len)
  40 {
  41         struct ccp_crypto_skcipher_alg *alg = ccp_crypto_skcipher_alg(tfm);
  42         struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
  43
  44         switch (key_len) {
  45         case AES_KEYSIZE_128:
  46                 ctx->u.aes.type = CCP_AES_TYPE_128;
  47                 break;
  48         case AES_KEYSIZE_192:
  49                 ctx->u.aes.type = CCP_AES_TYPE_192;
  50                 break;
  51         case AES_KEYSIZE_256:
  52                 ctx->u.aes.type = CCP_AES_TYPE_256;
  53                 break;
  54         default:
  55                 return -EINVAL;
  56         }
  57         ctx->u.aes.mode = alg->mode;
  58         ctx->u.aes.key_len = key_len;
  59
  60         memcpy(ctx->u.aes.key, key, key_len);
  61         sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len);
  62
  63         return 0;
  64 }
  65
  66 static int ccp_aes_crypt(struct skcipher_request *req, bool encrypt)
  67 {
  68         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  69         struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
  70         struct ccp_aes_req_ctx *rctx = skcipher_request_ctx_dma(req);
  71         struct scatterlist *iv_sg = NULL;
  72         unsigned int iv_len = 0;
  73
  74         if (!ctx->u.aes.key_len)
  75                 return -EINVAL;
  76
  77         if (((ctx->u.aes.mode == CCP_AES_MODE_ECB) ||
  78              (ctx->u.aes.mode == CCP_AES_MODE_CBC)) &&
  79             (req->cryptlen & (AES_BLOCK_SIZE - 1)))
  80                 return -EINVAL;
  81
  82         if (ctx->u.aes.mode != CCP_AES_MODE_ECB) {
  83                 if (!req->iv)
  84                         return -EINVAL;
  85
  86                 memcpy(rctx->iv, req->iv, AES_BLOCK_SIZE);
  87                 iv_sg = &rctx->iv_sg;
  88                 iv_len = AES_BLOCK_SIZE;
  89                 sg_init_one(iv_sg, rctx->iv, iv_len);
  90         }
  91
  92         memset(&rctx->cmd, 0, sizeof(rctx->cmd));
  93         INIT_LIST_HEAD(&rctx->cmd.entry);
  94         rctx->cmd.engine = CCP_ENGINE_AES;
  95         rctx->cmd.u.aes.type = ctx->u.aes.type;
  96         rctx->cmd.u.aes.mode = ctx->u.aes.mode;
  97         rctx->cmd.u.aes.action =
  98                 (encrypt) ? CCP_AES_ACTION_ENCRYPT : CCP_AES_ACTION_DECRYPT;
  99         rctx->cmd.u.aes.key = &ctx->u.aes.key_sg;
 100         rctx->cmd.u.aes.key_len = ctx->u.aes.key_len;
 101         rctx->cmd.u.aes.iv = iv_sg;
 102         rctx->cmd.u.aes.iv_len = iv_len;
 103         rctx->cmd.u.aes.src = req->src;
 104         rctx->cmd.u.aes.src_len = req->cryptlen;
 105         rctx->cmd.u.aes.dst = req->dst;
 106
 107         return ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
 108 }
 109
 110 static int ccp_aes_encrypt(struct skcipher_request *req)
 111 {
 112         return ccp_aes_crypt(req, true);
 113 }
 114
 115 static int ccp_aes_decrypt(struct skcipher_request *req)
 116 {
 117         return ccp_aes_crypt(req, false);
 118 }
 119
 120 static int ccp_aes_init_tfm(struct crypto_skcipher *tfm)
 121 {
 122         struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
 123
 124         ctx->complete = ccp_aes_complete;
 125         ctx->u.aes.key_len = 0;
 126
 127         crypto_skcipher_set_reqsize(tfm, sizeof(struct ccp_aes_req_ctx));
 128
 129         return 0;
 130 }
 131
 132 static int ccp_aes_rfc3686_complete(struct crypto_async_request *async_req,
 133                                     int ret)
 134 {
 135         struct skcipher_request *req = skcipher_request_cast(async_req);
 136         struct ccp_aes_req_ctx *rctx = skcipher_request_ctx_dma(req);
 137
 138         /* Restore the original pointer */
 139         req->iv = rctx->rfc3686_info;
 140
 141         return ccp_aes_complete(async_req, ret);
 142 }
 143
 144 static int ccp_aes_rfc3686_setkey(struct crypto_skcipher *tfm, const u8 *key,
 145                                   unsigned int key_len)
 146 {
 147         struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
 148
 149         if (key_len < CTR_RFC3686_NONCE_SIZE)
 150                 return -EINVAL;
 151
 152         key_len -= CTR_RFC3686_NONCE_SIZE;
 153         memcpy(ctx->u.aes.nonce, key + key_len, CTR_RFC3686_NONCE_SIZE);
 154
 155         return ccp_aes_setkey(tfm, key, key_len);
 156 }
 157
 158 static int ccp_aes_rfc3686_crypt(struct skcipher_request *req, bool encrypt)
 159 {
 160         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 161         struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
 162         struct ccp_aes_req_ctx *rctx = skcipher_request_ctx_dma(req);
 163         u8 *iv;
 164
 165         /* Initialize the CTR block */
 166         iv = rctx->rfc3686_iv;
 167         memcpy(iv, ctx->u.aes.nonce, CTR_RFC3686_NONCE_SIZE);
 168
 169         iv += CTR_RFC3686_NONCE_SIZE;
 170         memcpy(iv, req->iv, CTR_RFC3686_IV_SIZE);
 171
 172         iv += CTR_RFC3686_IV_SIZE;
 173         *(__be32 *)iv = cpu_to_be32(1);
 174
 175         /* Point to the new IV */
 176         rctx->rfc3686_info = req->iv;
 177         req->iv = rctx->rfc3686_iv;
 178
 179         return ccp_aes_crypt(req, encrypt);
 180 }
 181
 182 static int ccp_aes_rfc3686_encrypt(struct skcipher_request *req)
 183 {
 184         return ccp_aes_rfc3686_crypt(req, true);
 185 }
 186
 187 static int ccp_aes_rfc3686_decrypt(struct skcipher_request *req)
 188 {
 189         return ccp_aes_rfc3686_crypt(req, false);
 190 }
 191
 192 static int ccp_aes_rfc3686_init_tfm(struct crypto_skcipher *tfm)
 193 {
 194         struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
 195
 196         ctx->complete = ccp_aes_rfc3686_complete;
 197         ctx->u.aes.key_len = 0;
 198
 199         crypto_skcipher_set_reqsize_dma(tfm, sizeof(struct ccp_aes_req_ctx));
 200
 201         return 0;
 202 }
 203
 204 static const struct skcipher_alg ccp_aes_defaults = {
 205         .setkey                 = ccp_aes_setkey,
 206         .encrypt                = ccp_aes_encrypt,
 207         .decrypt                = ccp_aes_decrypt,
 208         .min_keysize            = AES_MIN_KEY_SIZE,
 209         .max_keysize            = AES_MAX_KEY_SIZE,
 210         .init                   = ccp_aes_init_tfm,
 211
 212         .base.cra_flags         = CRYPTO_ALG_ASYNC |
 213                                   CRYPTO_ALG_ALLOCATES_MEMORY |
 214                                   CRYPTO_ALG_KERN_DRIVER_ONLY |
 215                                   CRYPTO_ALG_NEED_FALLBACK,
 216         .base.cra_blocksize     = AES_BLOCK_SIZE,
 217         .base.cra_ctxsize       = sizeof(struct ccp_ctx) + CRYPTO_DMA_PADDING,
 218         .base.cra_priority      = CCP_CRA_PRIORITY,
 219         .base.cra_module        = THIS_MODULE,
 220 };
 221
 222 static const struct skcipher_alg ccp_aes_rfc3686_defaults = {
 223         .setkey                 = ccp_aes_rfc3686_setkey,
 224         .encrypt                = ccp_aes_rfc3686_encrypt,
 225         .decrypt                = ccp_aes_rfc3686_decrypt,
 226         .min_keysize            = AES_MIN_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
 227         .max_keysize            = AES_MAX_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
 228         .init                   = ccp_aes_rfc3686_init_tfm,
 229
 230         .base.cra_flags         = CRYPTO_ALG_ASYNC |
 231                                   CRYPTO_ALG_ALLOCATES_MEMORY |
 232                                   CRYPTO_ALG_KERN_DRIVER_ONLY |
 233                                   CRYPTO_ALG_NEED_FALLBACK,
 234         .base.cra_blocksize     = CTR_RFC3686_BLOCK_SIZE,
 235         .base.cra_ctxsize       = sizeof(struct ccp_ctx) + CRYPTO_DMA_PADDING,
 236         .base.cra_priority      = CCP_CRA_PRIORITY,
 237         .base.cra_module        = THIS_MODULE,
 238 };
 239
 240 struct ccp_aes_def {
 241         enum ccp_aes_mode mode;
 242         unsigned int version;
 243         const char *name;
 244         const char *driver_name;
 245         unsigned int blocksize;
 246         unsigned int ivsize;
 247         const struct skcipher_alg *alg_defaults;
 248 };
 249
 250 static struct ccp_aes_def aes_algs[] = {
 251         {
 252                 .mode           = CCP_AES_MODE_ECB,
 253                 .version        = CCP_VERSION(3, 0),
 254                 .name           = "ecb(aes)",
 255                 .driver_name    = "ecb-aes-ccp",
 256                 .blocksize      = AES_BLOCK_SIZE,
 257                 .ivsize         = 0,
 258                 .alg_defaults   = &ccp_aes_defaults,
 259         },
 260         {
 261                 .mode           = CCP_AES_MODE_CBC,
 262                 .version        = CCP_VERSION(3, 0),
 263                 .name           = "cbc(aes)",
 264                 .driver_name    = "cbc-aes-ccp",
 265                 .blocksize      = AES_BLOCK_SIZE,
 266                 .ivsize         = AES_BLOCK_SIZE,
 267                 .alg_defaults   = &ccp_aes_defaults,
 268         },
 269         {
 270                 .mode           = CCP_AES_MODE_CTR,
 271                 .version        = CCP_VERSION(3, 0),
 272                 .name           = "ctr(aes)",
 273                 .driver_name    = "ctr-aes-ccp",
 274                 .blocksize      = 1,
 275                 .ivsize         = AES_BLOCK_SIZE,
 276                 .alg_defaults   = &ccp_aes_defaults,
 277         },
 278         {
 279                 .mode           = CCP_AES_MODE_CTR,
 280                 .version        = CCP_VERSION(3, 0),
 281                 .name           = "rfc3686(ctr(aes))",
 282                 .driver_name    = "rfc3686-ctr-aes-ccp",
 283                 .blocksize      = 1,
 284                 .ivsize         = CTR_RFC3686_IV_SIZE,
 285                 .alg_defaults   = &ccp_aes_rfc3686_defaults,
 286         },
 287 };
 288
 289 static int ccp_register_aes_alg(struct list_head *head,
 290                                 const struct ccp_aes_def *def)
 291 {
 292         struct ccp_crypto_skcipher_alg *ccp_alg;
 293         struct skcipher_alg *alg;
 294         int ret;
 295
 296         ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
 297         if (!ccp_alg)
 298                 return -ENOMEM;
 299
 300         INIT_LIST_HEAD(&ccp_alg->entry);
 301
 302         ccp_alg->mode = def->mode;
 303
 304         /* Copy the defaults and override as necessary */
 305         alg = &ccp_alg->alg;
 306         *alg = *def->alg_defaults;
 307         snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
 308         snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
 309                  def->driver_name);
 310         alg->base.cra_blocksize = def->blocksize;
 311         alg->ivsize = def->ivsize;
 312
 313         ret = crypto_register_skcipher(alg);
 314         if (ret) {
 315                 pr_err("%s skcipher algorithm registration error (%d)\n",
 316                        alg->base.cra_name, ret);
 317                 kfree(ccp_alg);
 318                 return ret;
 319         }
 320
 321         list_add(&ccp_alg->entry, head);
 322
 323         return 0;
 324 }
 325
 326 int ccp_register_aes_algs(struct list_head *head)
 327 {
 328         int i, ret;
 329         unsigned int ccpversion = ccp_version();
 330
 331         for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
 332                 if (aes_algs[i].version > ccpversion)
 333                         continue;
 334                 ret = ccp_register_aes_alg(head, &aes_algs[i]);
 335                 if (ret)
 336                         return ret;
 337         }
 338
 339         return 0;
 340 }