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_tfm_ctx(req->base.tfm);
  26         struct ccp_aes_req_ctx *rctx = skcipher_request_ctx(req);
  27
  28         if (ret)
  29                 return ret;
  30
  31         if (ctx->u.aes.mode != CCP_AES_MODE_ECB)
  32                 memcpy(req->iv, rctx->iv, AES_BLOCK_SIZE);
  33
  34         return 0;
  35 }
  36
  37 static int ccp_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
  38                           unsigned int key_len)
  39 {
  40         struct ccp_crypto_skcipher_alg *alg = ccp_crypto_skcipher_alg(tfm);
  41         struct ccp_ctx *ctx = crypto_skcipher_ctx(tfm);
  42
  43         switch (key_len) {
  44         case AES_KEYSIZE_128:
  45                 ctx->u.aes.type = CCP_AES_TYPE_128;
  46                 break;
  47         case AES_KEYSIZE_192:
  48                 ctx->u.aes.type = CCP_AES_TYPE_192;
  49                 break;
  50         case AES_KEYSIZE_256:
  51                 ctx->u.aes.type = CCP_AES_TYPE_256;
  52                 break;
  53         default:
  54                 return -EINVAL;
  55         }
  56         ctx->u.aes.mode = alg->mode;
  57         ctx->u.aes.key_len = key_len;
  58
  59         memcpy(ctx->u.aes.key, key, key_len);
  60         sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len);
  61
  62         return 0;
  63 }
  64
  65 static int ccp_aes_crypt(struct skcipher_request *req, bool encrypt)
  66 {
  67         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  68         struct ccp_ctx *ctx = crypto_skcipher_ctx(tfm);
  69         struct ccp_aes_req_ctx *rctx = skcipher_request_ctx(req);
  70         struct scatterlist *iv_sg = NULL;
  71         unsigned int iv_len = 0;
  72         int ret;
  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         ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
 108
 109         return ret;
 110 }
 111
 112 static int ccp_aes_encrypt(struct skcipher_request *req)
 113 {
 114         return ccp_aes_crypt(req, true);
 115 }
 116
 117 static int ccp_aes_decrypt(struct skcipher_request *req)
 118 {
 119         return ccp_aes_crypt(req, false);
 120 }
 121
 122 static int ccp_aes_init_tfm(struct crypto_skcipher *tfm)
 123 {
 124         struct ccp_ctx *ctx = crypto_skcipher_ctx(tfm);
 125
 126         ctx->complete = ccp_aes_complete;
 127         ctx->u.aes.key_len = 0;
 128
 129         crypto_skcipher_set_reqsize(tfm, sizeof(struct ccp_aes_req_ctx));
 130
 131         return 0;
 132 }
 133
 134 static int ccp_aes_rfc3686_complete(struct crypto_async_request *async_req,
 135                                     int ret)
 136 {
 137         struct skcipher_request *req = skcipher_request_cast(async_req);
 138         struct ccp_aes_req_ctx *rctx = skcipher_request_ctx(req);
 139
 140         /* Restore the original pointer */
 141         req->iv = rctx->rfc3686_info;
 142
 143         return ccp_aes_complete(async_req, ret);
 144 }
 145
 146 static int ccp_aes_rfc3686_setkey(struct crypto_skcipher *tfm, const u8 *key,
 147                                   unsigned int key_len)
 148 {
 149         struct ccp_ctx *ctx = crypto_skcipher_ctx(tfm);
 150
 151         if (key_len < CTR_RFC3686_NONCE_SIZE)
 152                 return -EINVAL;
 153
 154         key_len -= CTR_RFC3686_NONCE_SIZE;
 155         memcpy(ctx->u.aes.nonce, key + key_len, CTR_RFC3686_NONCE_SIZE);
 156
 157         return ccp_aes_setkey(tfm, key, key_len);
 158 }
 159
 160 static int ccp_aes_rfc3686_crypt(struct skcipher_request *req, bool encrypt)
 161 {
 162         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 163         struct ccp_ctx *ctx = crypto_skcipher_ctx(tfm);
 164         struct ccp_aes_req_ctx *rctx = skcipher_request_ctx(req);
 165         u8 *iv;
 166
 167         /* Initialize the CTR block */
 168         iv = rctx->rfc3686_iv;
 169         memcpy(iv, ctx->u.aes.nonce, CTR_RFC3686_NONCE_SIZE);
 170
 171         iv += CTR_RFC3686_NONCE_SIZE;
 172         memcpy(iv, req->iv, CTR_RFC3686_IV_SIZE);
 173
 174         iv += CTR_RFC3686_IV_SIZE;
 175         *(__be32 *)iv = cpu_to_be32(1);
 176
 177         /* Point to the new IV */
 178         rctx->rfc3686_info = req->iv;
 179         req->iv = rctx->rfc3686_iv;
 180
 181         return ccp_aes_crypt(req, encrypt);
 182 }
 183
 184 static int ccp_aes_rfc3686_encrypt(struct skcipher_request *req)
 185 {
 186         return ccp_aes_rfc3686_crypt(req, true);
 187 }
 188
 189 static int ccp_aes_rfc3686_decrypt(struct skcipher_request *req)
 190 {
 191         return ccp_aes_rfc3686_crypt(req, false);
 192 }
 193
 194 static int ccp_aes_rfc3686_init_tfm(struct crypto_skcipher *tfm)
 195 {
 196         struct ccp_ctx *ctx = crypto_skcipher_ctx(tfm);
 197
 198         ctx->complete = ccp_aes_rfc3686_complete;
 199         ctx->u.aes.key_len = 0;
 200
 201         crypto_skcipher_set_reqsize(tfm, sizeof(struct ccp_aes_req_ctx));
 202
 203         return 0;
 204 }
 205
 206 static const struct skcipher_alg ccp_aes_defaults = {
 207         .setkey                 = ccp_aes_setkey,
 208         .encrypt                = ccp_aes_encrypt,
 209         .decrypt                = ccp_aes_decrypt,
 210         .min_keysize            = AES_MIN_KEY_SIZE,
 211         .max_keysize            = AES_MAX_KEY_SIZE,
 212         .init                   = ccp_aes_init_tfm,
 213
 214         .base.cra_flags         = CRYPTO_ALG_ASYNC |
 215                                   CRYPTO_ALG_KERN_DRIVER_ONLY |
 216                                   CRYPTO_ALG_NEED_FALLBACK,
 217         .base.cra_blocksize     = AES_BLOCK_SIZE,
 218         .base.cra_ctxsize       = sizeof(struct ccp_ctx),
 219         .base.cra_priority      = CCP_CRA_PRIORITY,
 220         .base.cra_module        = THIS_MODULE,
 221 };
 222
 223 static const struct skcipher_alg ccp_aes_rfc3686_defaults = {
 224         .setkey                 = ccp_aes_rfc3686_setkey,
 225         .encrypt                = ccp_aes_rfc3686_encrypt,
 226         .decrypt                = ccp_aes_rfc3686_decrypt,
 227         .min_keysize            = AES_MIN_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
 228         .max_keysize            = AES_MAX_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
 229         .init                   = ccp_aes_rfc3686_init_tfm,
 230
 231         .base.cra_flags         = CRYPTO_ALG_ASYNC |
 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),
 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_CFB,
 271                 .version        = CCP_VERSION(3, 0),
 272                 .name           = "cfb(aes)",
 273                 .driver_name    = "cfb-aes-ccp",
 274                 .blocksize      = 1,
 275                 .ivsize         = AES_BLOCK_SIZE,
 276                 .alg_defaults   = &ccp_aes_defaults,
 277         },
 278         {
 279                 .mode           = CCP_AES_MODE_OFB,
 280                 .version        = CCP_VERSION(3, 0),
 281                 .name           = "ofb(aes)",
 282                 .driver_name    = "ofb-aes-ccp",
 283                 .blocksize      = 1,
 284                 .ivsize         = AES_BLOCK_SIZE,
 285                 .alg_defaults   = &ccp_aes_defaults,
 286         },
 287         {
 288                 .mode           = CCP_AES_MODE_CTR,
 289                 .version        = CCP_VERSION(3, 0),
 290                 .name           = "ctr(aes)",
 291                 .driver_name    = "ctr-aes-ccp",
 292                 .blocksize      = 1,
 293                 .ivsize         = AES_BLOCK_SIZE,
 294                 .alg_defaults   = &ccp_aes_defaults,
 295         },
 296         {
 297                 .mode           = CCP_AES_MODE_CTR,
 298                 .version        = CCP_VERSION(3, 0),
 299                 .name           = "rfc3686(ctr(aes))",
 300                 .driver_name    = "rfc3686-ctr-aes-ccp",
 301                 .blocksize      = 1,
 302                 .ivsize         = CTR_RFC3686_IV_SIZE,
 303                 .alg_defaults   = &ccp_aes_rfc3686_defaults,
 304         },
 305 };
 306
 307 static int ccp_register_aes_alg(struct list_head *head,
 308                                 const struct ccp_aes_def *def)
 309 {
 310         struct ccp_crypto_skcipher_alg *ccp_alg;
 311         struct skcipher_alg *alg;
 312         int ret;
 313
 314         ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
 315         if (!ccp_alg)
 316                 return -ENOMEM;
 317
 318         INIT_LIST_HEAD(&ccp_alg->entry);
 319
 320         ccp_alg->mode = def->mode;
 321
 322         /* Copy the defaults and override as necessary */
 323         alg = &ccp_alg->alg;
 324         *alg = *def->alg_defaults;
 325         snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
 326         snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
 327                  def->driver_name);
 328         alg->base.cra_blocksize = def->blocksize;
 329         alg->ivsize = def->ivsize;
 330
 331         ret = crypto_register_skcipher(alg);
 332         if (ret) {
 333                 pr_err("%s skcipher algorithm registration error (%d)\n",
 334                        alg->base.cra_name, ret);
 335                 kfree(ccp_alg);
 336                 return ret;
 337         }
 338
 339         list_add(&ccp_alg->entry, head);
 340
 341         return 0;
 342 }
 343
 344 int ccp_register_aes_algs(struct list_head *head)
 345 {
 346         int i, ret;
 347         unsigned int ccpversion = ccp_version();
 348
 349         for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
 350                 if (aes_algs[i].version > ccpversion)
 351                         continue;
 352                 ret = ccp_register_aes_alg(head, &aes_algs[i]);
 353                 if (ret)
 354                         return ret;
 355         }
 356
 357         return 0;
 358 }