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

   1 /*
   2  * AMD Cryptographic Coprocessor (CCP) AES crypto API support
   3  *
   4  * Copyright (C) 2013 Advanced Micro Devices, Inc.
   5  *
   6  * Author: Tom Lendacky <thomas.lendacky@amd.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/sched.h>
  15 #include <linux/delay.h>
  16 #include <linux/scatterlist.h>
  17 #include <linux/crypto.h>
  18 #include <crypto/algapi.h>
  19 #include <crypto/aes.h>
  20 #include <crypto/ctr.h>
  21 #include <crypto/scatterwalk.h>
  22
  23 #include "ccp-crypto.h"
  24
  25
  26 static int ccp_aes_complete(struct crypto_async_request *async_req, int ret)
  27 {
  28         struct ablkcipher_request *req = ablkcipher_request_cast(async_req);
  29         struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
  30         struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
  31
  32         if (ret)
  33                 return ret;
  34
  35         if (ctx->u.aes.mode != CCP_AES_MODE_ECB)
  36                 memcpy(req->info, rctx->iv, AES_BLOCK_SIZE);
  37
  38         return 0;
  39 }
  40
  41 static int ccp_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
  42                           unsigned int key_len)
  43 {
  44         struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ablkcipher_tfm(tfm));
  45         struct ccp_crypto_ablkcipher_alg *alg =
  46                 ccp_crypto_ablkcipher_alg(crypto_ablkcipher_tfm(tfm));
  47
  48         switch (key_len) {
  49         case AES_KEYSIZE_128:
  50                 ctx->u.aes.type = CCP_AES_TYPE_128;
  51                 break;
  52         case AES_KEYSIZE_192:
  53                 ctx->u.aes.type = CCP_AES_TYPE_192;
  54                 break;
  55         case AES_KEYSIZE_256:
  56                 ctx->u.aes.type = CCP_AES_TYPE_256;
  57                 break;
  58         default:
  59                 crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
  60                 return -EINVAL;
  61         }
  62         ctx->u.aes.mode = alg->mode;
  63         ctx->u.aes.key_len = key_len;
  64
  65         memcpy(ctx->u.aes.key, key, key_len);
  66         sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len);
  67
  68         return 0;
  69 }
  70
  71 static int ccp_aes_crypt(struct ablkcipher_request *req, bool encrypt)
  72 {
  73         struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
  74         struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
  75         struct scatterlist *iv_sg = NULL;
  76         unsigned int iv_len = 0;
  77         int ret;
  78
  79         if (!ctx->u.aes.key_len)
  80                 return -EINVAL;
  81
  82         if (((ctx->u.aes.mode == CCP_AES_MODE_ECB) ||
  83              (ctx->u.aes.mode == CCP_AES_MODE_CBC) ||
  84              (ctx->u.aes.mode == CCP_AES_MODE_CFB)) &&
  85             (req->nbytes & (AES_BLOCK_SIZE - 1)))
  86                 return -EINVAL;
  87
  88         if (ctx->u.aes.mode != CCP_AES_MODE_ECB) {
  89                 if (!req->info)
  90                         return -EINVAL;
  91
  92                 memcpy(rctx->iv, req->info, AES_BLOCK_SIZE);
  93                 iv_sg = &rctx->iv_sg;
  94                 iv_len = AES_BLOCK_SIZE;
  95                 sg_init_one(iv_sg, rctx->iv, iv_len);
  96         }
  97
  98         memset(&rctx->cmd, 0, sizeof(rctx->cmd));
  99         INIT_LIST_HEAD(&rctx->cmd.entry);
 100         rctx->cmd.engine = CCP_ENGINE_AES;
 101         rctx->cmd.u.aes.type = ctx->u.aes.type;
 102         rctx->cmd.u.aes.mode = ctx->u.aes.mode;
 103         rctx->cmd.u.aes.action =
 104                 (encrypt) ? CCP_AES_ACTION_ENCRYPT : CCP_AES_ACTION_DECRYPT;
 105         rctx->cmd.u.aes.key = &ctx->u.aes.key_sg;
 106         rctx->cmd.u.aes.key_len = ctx->u.aes.key_len;
 107         rctx->cmd.u.aes.iv = iv_sg;
 108         rctx->cmd.u.aes.iv_len = iv_len;
 109         rctx->cmd.u.aes.src = req->src;
 110         rctx->cmd.u.aes.src_len = req->nbytes;
 111         rctx->cmd.u.aes.dst = req->dst;
 112
 113         ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
 114
 115         return ret;
 116 }
 117
 118 static int ccp_aes_encrypt(struct ablkcipher_request *req)
 119 {
 120         return ccp_aes_crypt(req, true);
 121 }
 122
 123 static int ccp_aes_decrypt(struct ablkcipher_request *req)
 124 {
 125         return ccp_aes_crypt(req, false);
 126 }
 127
 128 static int ccp_aes_cra_init(struct crypto_tfm *tfm)
 129 {
 130         struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
 131
 132         ctx->complete = ccp_aes_complete;
 133         ctx->u.aes.key_len = 0;
 134
 135         tfm->crt_ablkcipher.reqsize = sizeof(struct ccp_aes_req_ctx);
 136
 137         return 0;
 138 }
 139
 140 static void ccp_aes_cra_exit(struct crypto_tfm *tfm)
 141 {
 142 }
 143
 144 static int ccp_aes_rfc3686_complete(struct crypto_async_request *async_req,
 145                                     int ret)
 146 {
 147         struct ablkcipher_request *req = ablkcipher_request_cast(async_req);
 148         struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
 149
 150         /* Restore the original pointer */
 151         req->info = rctx->rfc3686_info;
 152
 153         return ccp_aes_complete(async_req, ret);
 154 }
 155
 156 static int ccp_aes_rfc3686_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
 157                                   unsigned int key_len)
 158 {
 159         struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ablkcipher_tfm(tfm));
 160
 161         if (key_len < CTR_RFC3686_NONCE_SIZE)
 162                 return -EINVAL;
 163
 164         key_len -= CTR_RFC3686_NONCE_SIZE;
 165         memcpy(ctx->u.aes.nonce, key + key_len, CTR_RFC3686_NONCE_SIZE);
 166
 167         return ccp_aes_setkey(tfm, key, key_len);
 168 }
 169
 170 static int ccp_aes_rfc3686_crypt(struct ablkcipher_request *req, bool encrypt)
 171 {
 172         struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
 173         struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
 174         u8 *iv;
 175
 176         /* Initialize the CTR block */
 177         iv = rctx->rfc3686_iv;
 178         memcpy(iv, ctx->u.aes.nonce, CTR_RFC3686_NONCE_SIZE);
 179
 180         iv += CTR_RFC3686_NONCE_SIZE;
 181         memcpy(iv, req->info, CTR_RFC3686_IV_SIZE);
 182
 183         iv += CTR_RFC3686_IV_SIZE;
 184         *(__be32 *)iv = cpu_to_be32(1);
 185
 186         /* Point to the new IV */
 187         rctx->rfc3686_info = req->info;
 188         req->info = rctx->rfc3686_iv;
 189
 190         return ccp_aes_crypt(req, encrypt);
 191 }
 192
 193 static int ccp_aes_rfc3686_encrypt(struct ablkcipher_request *req)
 194 {
 195         return ccp_aes_rfc3686_crypt(req, true);
 196 }
 197
 198 static int ccp_aes_rfc3686_decrypt(struct ablkcipher_request *req)
 199 {
 200         return ccp_aes_rfc3686_crypt(req, false);
 201 }
 202
 203 static int ccp_aes_rfc3686_cra_init(struct crypto_tfm *tfm)
 204 {
 205         struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
 206
 207         ctx->complete = ccp_aes_rfc3686_complete;
 208         ctx->u.aes.key_len = 0;
 209
 210         tfm->crt_ablkcipher.reqsize = sizeof(struct ccp_aes_req_ctx);
 211
 212         return 0;
 213 }
 214
 215 static void ccp_aes_rfc3686_cra_exit(struct crypto_tfm *tfm)
 216 {
 217 }
 218
 219 static struct crypto_alg ccp_aes_defaults = {
 220         .cra_flags      = CRYPTO_ALG_TYPE_ABLKCIPHER |
 221                           CRYPTO_ALG_ASYNC |
 222                           CRYPTO_ALG_KERN_DRIVER_ONLY |
 223                           CRYPTO_ALG_NEED_FALLBACK,
 224         .cra_blocksize  = AES_BLOCK_SIZE,
 225         .cra_ctxsize    = sizeof(struct ccp_ctx),
 226         .cra_priority   = CCP_CRA_PRIORITY,
 227         .cra_type       = &crypto_ablkcipher_type,
 228         .cra_init       = ccp_aes_cra_init,
 229         .cra_exit       = ccp_aes_cra_exit,
 230         .cra_module     = THIS_MODULE,
 231         .cra_ablkcipher = {
 232                 .setkey         = ccp_aes_setkey,
 233                 .encrypt        = ccp_aes_encrypt,
 234                 .decrypt        = ccp_aes_decrypt,
 235                 .min_keysize    = AES_MIN_KEY_SIZE,
 236                 .max_keysize    = AES_MAX_KEY_SIZE,
 237         },
 238 };
 239
 240 static struct crypto_alg ccp_aes_rfc3686_defaults = {
 241         .cra_flags      = CRYPTO_ALG_TYPE_ABLKCIPHER |
 242                            CRYPTO_ALG_ASYNC |
 243                            CRYPTO_ALG_KERN_DRIVER_ONLY |
 244                            CRYPTO_ALG_NEED_FALLBACK,
 245         .cra_blocksize  = CTR_RFC3686_BLOCK_SIZE,
 246         .cra_ctxsize    = sizeof(struct ccp_ctx),
 247         .cra_priority   = CCP_CRA_PRIORITY,
 248         .cra_type       = &crypto_ablkcipher_type,
 249         .cra_init       = ccp_aes_rfc3686_cra_init,
 250         .cra_exit       = ccp_aes_rfc3686_cra_exit,
 251         .cra_module     = THIS_MODULE,
 252         .cra_ablkcipher = {
 253                 .setkey         = ccp_aes_rfc3686_setkey,
 254                 .encrypt        = ccp_aes_rfc3686_encrypt,
 255                 .decrypt        = ccp_aes_rfc3686_decrypt,
 256                 .min_keysize    = AES_MIN_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
 257                 .max_keysize    = AES_MAX_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
 258         },
 259 };
 260
 261 struct ccp_aes_def {
 262         enum ccp_aes_mode mode;
 263         const char *name;
 264         const char *driver_name;
 265         unsigned int blocksize;
 266         unsigned int ivsize;
 267         struct crypto_alg *alg_defaults;
 268 };
 269
 270 static struct ccp_aes_def aes_algs[] = {
 271         {
 272                 .mode           = CCP_AES_MODE_ECB,
 273                 .name           = "ecb(aes)",
 274                 .driver_name    = "ecb-aes-ccp",
 275                 .blocksize      = AES_BLOCK_SIZE,
 276                 .ivsize         = 0,
 277                 .alg_defaults   = &ccp_aes_defaults,
 278         },
 279         {
 280                 .mode           = CCP_AES_MODE_CBC,
 281                 .name           = "cbc(aes)",
 282                 .driver_name    = "cbc-aes-ccp",
 283                 .blocksize      = AES_BLOCK_SIZE,
 284                 .ivsize         = AES_BLOCK_SIZE,
 285                 .alg_defaults   = &ccp_aes_defaults,
 286         },
 287         {
 288                 .mode           = CCP_AES_MODE_CFB,
 289                 .name           = "cfb(aes)",
 290                 .driver_name    = "cfb-aes-ccp",
 291                 .blocksize      = AES_BLOCK_SIZE,
 292                 .ivsize         = AES_BLOCK_SIZE,
 293                 .alg_defaults   = &ccp_aes_defaults,
 294         },
 295         {
 296                 .mode           = CCP_AES_MODE_OFB,
 297                 .name           = "ofb(aes)",
 298                 .driver_name    = "ofb-aes-ccp",
 299                 .blocksize      = 1,
 300                 .ivsize         = AES_BLOCK_SIZE,
 301                 .alg_defaults   = &ccp_aes_defaults,
 302         },
 303         {
 304                 .mode           = CCP_AES_MODE_CTR,
 305                 .name           = "ctr(aes)",
 306                 .driver_name    = "ctr-aes-ccp",
 307                 .blocksize      = 1,
 308                 .ivsize         = AES_BLOCK_SIZE,
 309                 .alg_defaults   = &ccp_aes_defaults,
 310         },
 311         {
 312                 .mode           = CCP_AES_MODE_CTR,
 313                 .name           = "rfc3686(ctr(aes))",
 314                 .driver_name    = "rfc3686-ctr-aes-ccp",
 315                 .blocksize      = 1,
 316                 .ivsize         = CTR_RFC3686_IV_SIZE,
 317                 .alg_defaults   = &ccp_aes_rfc3686_defaults,
 318         },
 319 };
 320
 321 static int ccp_register_aes_alg(struct list_head *head,
 322                                 const struct ccp_aes_def *def)
 323 {
 324         struct ccp_crypto_ablkcipher_alg *ccp_alg;
 325         struct crypto_alg *alg;
 326         int ret;
 327
 328         ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
 329         if (!ccp_alg)
 330                 return -ENOMEM;
 331
 332         INIT_LIST_HEAD(&ccp_alg->entry);
 333
 334         ccp_alg->mode = def->mode;
 335
 336         /* Copy the defaults and override as necessary */
 337         alg = &ccp_alg->alg;
 338         *alg = *def->alg_defaults;
 339         snprintf(alg->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
 340         snprintf(alg->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
 341                  def->driver_name);
 342         alg->cra_blocksize = def->blocksize;
 343         alg->cra_ablkcipher.ivsize = def->ivsize;
 344
 345         ret = crypto_register_alg(alg);
 346         if (ret) {
 347                 pr_err("%s ablkcipher algorithm registration error (%d)\n",
 348                         alg->cra_name, ret);
 349                 kfree(ccp_alg);
 350                 return ret;
 351         }
 352
 353         list_add(&ccp_alg->entry, head);
 354
 355         return 0;
 356 }
 357
 358 int ccp_register_aes_algs(struct list_head *head)
 359 {
 360         int i, ret;
 361
 362         for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
 363                 ret = ccp_register_aes_alg(head, &aes_algs[i]);
 364                 if (ret)
 365                         return ret;
 366         }
 367
 368         return 0;
 369 }