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