drivers/crypto/allwinner/sun8i-ss/sun8i-ss-cipher.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * sun8i-ss-cipher.c - hardware cryptographic offloader for
   4  * Allwinner A80/A83T SoC
   5  *
   6  * Copyright (C) 2016-2019 Corentin LABBE <clabbe.montjoie@gmail.com>
   7  *
   8  * This file add support for AES cipher with 128,192,256 bits keysize in
   9  * CBC and ECB mode.
  10  *
  11  * You could find a link for the datasheet in Documentation/arm/sunxi.rst
  12  */
  13
  14 #include <linux/crypto.h>
  15 #include <linux/dma-mapping.h>
  16 #include <linux/io.h>
  17 #include <linux/pm_runtime.h>
  18 #include <crypto/scatterwalk.h>
  19 #include <crypto/internal/skcipher.h>
  20 #include "sun8i-ss.h"
  21
  22 static bool sun8i_ss_need_fallback(struct skcipher_request *areq)
  23 {
  24         struct scatterlist *in_sg = areq->src;
  25         struct scatterlist *out_sg = areq->dst;
  26         struct scatterlist *sg;
  27
  28         if (areq->cryptlen == 0 || areq->cryptlen % 16)
  29                 return true;
  30
  31         if (sg_nents(areq->src) > 8 || sg_nents(areq->dst) > 8)
  32                 return true;
  33
  34         sg = areq->src;
  35         while (sg) {
  36                 if ((sg->length % 16) != 0)
  37                         return true;
  38                 if ((sg_dma_len(sg) % 16) != 0)
  39                         return true;
  40                 if (!IS_ALIGNED(sg->offset, 16))
  41                         return true;
  42                 sg = sg_next(sg);
  43         }
  44         sg = areq->dst;
  45         while (sg) {
  46                 if ((sg->length % 16) != 0)
  47                         return true;
  48                 if ((sg_dma_len(sg) % 16) != 0)
  49                         return true;
  50                 if (!IS_ALIGNED(sg->offset, 16))
  51                         return true;
  52                 sg = sg_next(sg);
  53         }
  54
  55         /* SS need same numbers of SG (with same length) for source and destination */
  56         in_sg = areq->src;
  57         out_sg = areq->dst;
  58         while (in_sg && out_sg) {
  59                 if (in_sg->length != out_sg->length)
  60                         return true;
  61                 in_sg = sg_next(in_sg);
  62                 out_sg = sg_next(out_sg);
  63         }
  64         if (in_sg || out_sg)
  65                 return true;
  66         return false;
  67 }
  68
  69 static int sun8i_ss_cipher_fallback(struct skcipher_request *areq)
  70 {
  71         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
  72         struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
  73         struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
  74         int err;
  75
  76 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
  77         struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
  78         struct sun8i_ss_alg_template *algt;
  79
  80         algt = container_of(alg, struct sun8i_ss_alg_template, alg.skcipher);
  81         algt->stat_fb++;
  82 #endif
  83         skcipher_request_set_tfm(&rctx->fallback_req, op->fallback_tfm);
  84         skcipher_request_set_callback(&rctx->fallback_req, areq->base.flags,
  85                                       areq->base.complete, areq->base.data);
  86         skcipher_request_set_crypt(&rctx->fallback_req, areq->src, areq->dst,
  87                                    areq->cryptlen, areq->iv);
  88         if (rctx->op_dir & SS_DECRYPTION)
  89                 err = crypto_skcipher_decrypt(&rctx->fallback_req);
  90         else
  91                 err = crypto_skcipher_encrypt(&rctx->fallback_req);
  92         return err;
  93 }
  94
  95 static int sun8i_ss_cipher(struct skcipher_request *areq)
  96 {
  97         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
  98         struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
  99         struct sun8i_ss_dev *ss = op->ss;
 100         struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
 101         struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
 102         struct sun8i_ss_alg_template *algt;
 103         struct scatterlist *sg;
 104         unsigned int todo, len, offset, ivsize;
 105         void *backup_iv = NULL;
 106         int nr_sgs = 0;
 107         int nr_sgd = 0;
 108         int err = 0;
 109         int i;
 110
 111         algt = container_of(alg, struct sun8i_ss_alg_template, alg.skcipher);
 112
 113         dev_dbg(ss->dev, "%s %s %u %x IV(%p %u) key=%u\n", __func__,
 114                 crypto_tfm_alg_name(areq->base.tfm),
 115                 areq->cryptlen,
 116                 rctx->op_dir, areq->iv, crypto_skcipher_ivsize(tfm),
 117                 op->keylen);
 118
 119 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
 120         algt->stat_req++;
 121 #endif
 122
 123         rctx->op_mode = ss->variant->op_mode[algt->ss_blockmode];
 124         rctx->method = ss->variant->alg_cipher[algt->ss_algo_id];
 125         rctx->keylen = op->keylen;
 126
 127         rctx->p_key = dma_map_single(ss->dev, op->key, op->keylen, DMA_TO_DEVICE);
 128         if (dma_mapping_error(ss->dev, rctx->p_key)) {
 129                 dev_err(ss->dev, "Cannot DMA MAP KEY\n");
 130                 err = -EFAULT;
 131                 goto theend;
 132         }
 133
 134         ivsize = crypto_skcipher_ivsize(tfm);
 135         if (areq->iv && crypto_skcipher_ivsize(tfm) > 0) {
 136                 rctx->ivlen = ivsize;
 137                 rctx->biv = kzalloc(ivsize, GFP_KERNEL | GFP_DMA);
 138                 if (!rctx->biv) {
 139                         err = -ENOMEM;
 140                         goto theend_key;
 141                 }
 142                 if (rctx->op_dir & SS_DECRYPTION) {
 143                         backup_iv = kzalloc(ivsize, GFP_KERNEL);
 144                         if (!backup_iv) {
 145                                 err = -ENOMEM;
 146                                 goto theend_key;
 147                         }
 148                         offset = areq->cryptlen - ivsize;
 149                         scatterwalk_map_and_copy(backup_iv, areq->src, offset,
 150                                                  ivsize, 0);
 151                 }
 152                 memcpy(rctx->biv, areq->iv, ivsize);
 153                 rctx->p_iv = dma_map_single(ss->dev, rctx->biv, rctx->ivlen,
 154                                             DMA_TO_DEVICE);
 155                 if (dma_mapping_error(ss->dev, rctx->p_iv)) {
 156                         dev_err(ss->dev, "Cannot DMA MAP IV\n");
 157                         err = -ENOMEM;
 158                         goto theend_iv;
 159                 }
 160         }
 161         if (areq->src == areq->dst) {
 162                 nr_sgs = dma_map_sg(ss->dev, areq->src, sg_nents(areq->src),
 163                                     DMA_BIDIRECTIONAL);
 164                 if (nr_sgs <= 0 || nr_sgs > 8) {
 165                         dev_err(ss->dev, "Invalid sg number %d\n", nr_sgs);
 166                         err = -EINVAL;
 167                         goto theend_iv;
 168                 }
 169                 nr_sgd = nr_sgs;
 170         } else {
 171                 nr_sgs = dma_map_sg(ss->dev, areq->src, sg_nents(areq->src),
 172                                     DMA_TO_DEVICE);
 173                 if (nr_sgs <= 0 || nr_sgs > 8) {
 174                         dev_err(ss->dev, "Invalid sg number %d\n", nr_sgs);
 175                         err = -EINVAL;
 176                         goto theend_iv;
 177                 }
 178                 nr_sgd = dma_map_sg(ss->dev, areq->dst, sg_nents(areq->dst),
 179                                     DMA_FROM_DEVICE);
 180                 if (nr_sgd <= 0 || nr_sgd > 8) {
 181                         dev_err(ss->dev, "Invalid sg number %d\n", nr_sgd);
 182                         err = -EINVAL;
 183                         goto theend_sgs;
 184                 }
 185         }
 186
 187         len = areq->cryptlen;
 188         i = 0;
 189         sg = areq->src;
 190         while (i < nr_sgs && sg && len) {
 191                 if (sg_dma_len(sg) == 0)
 192                         goto sgs_next;
 193                 rctx->t_src[i].addr = sg_dma_address(sg);
 194                 todo = min(len, sg_dma_len(sg));
 195                 rctx->t_src[i].len = todo / 4;
 196                 dev_dbg(ss->dev, "%s total=%u SGS(%d %u off=%d) todo=%u\n", __func__,
 197                         areq->cryptlen, i, rctx->t_src[i].len, sg->offset, todo);
 198                 len -= todo;
 199                 i++;
 200 sgs_next:
 201                 sg = sg_next(sg);
 202         }
 203         if (len > 0) {
 204                 dev_err(ss->dev, "remaining len %d\n", len);
 205                 err = -EINVAL;
 206                 goto theend_sgs;
 207         }
 208
 209         len = areq->cryptlen;
 210         i = 0;
 211         sg = areq->dst;
 212         while (i < nr_sgd && sg && len) {
 213                 if (sg_dma_len(sg) == 0)
 214                         goto sgd_next;
 215                 rctx->t_dst[i].addr = sg_dma_address(sg);
 216                 todo = min(len, sg_dma_len(sg));
 217                 rctx->t_dst[i].len = todo / 4;
 218                 dev_dbg(ss->dev, "%s total=%u SGD(%d %u off=%d) todo=%u\n", __func__,
 219                         areq->cryptlen, i, rctx->t_dst[i].len, sg->offset, todo);
 220                 len -= todo;
 221                 i++;
 222 sgd_next:
 223                 sg = sg_next(sg);
 224         }
 225         if (len > 0) {
 226                 dev_err(ss->dev, "remaining len %d\n", len);
 227                 err = -EINVAL;
 228                 goto theend_sgs;
 229         }
 230
 231         err = sun8i_ss_run_task(ss, rctx, crypto_tfm_alg_name(areq->base.tfm));
 232
 233 theend_sgs:
 234         if (areq->src == areq->dst) {
 235                 dma_unmap_sg(ss->dev, areq->src, nr_sgs, DMA_BIDIRECTIONAL);
 236         } else {
 237                 dma_unmap_sg(ss->dev, areq->src, nr_sgs, DMA_TO_DEVICE);
 238                 dma_unmap_sg(ss->dev, areq->dst, nr_sgd, DMA_FROM_DEVICE);
 239         }
 240
 241 theend_iv:
 242         if (rctx->p_iv)
 243                 dma_unmap_single(ss->dev, rctx->p_iv, rctx->ivlen,
 244                                  DMA_TO_DEVICE);
 245
 246         if (areq->iv && ivsize > 0) {
 247                 if (rctx->biv) {
 248                         offset = areq->cryptlen - ivsize;
 249                         if (rctx->op_dir & SS_DECRYPTION) {
 250                                 memcpy(areq->iv, backup_iv, ivsize);
 251                                 kfree_sensitive(backup_iv);
 252                         } else {
 253                                 scatterwalk_map_and_copy(areq->iv, areq->dst, offset,
 254                                                          ivsize, 0);
 255                         }
 256                         kfree(rctx->biv);
 257                 }
 258         }
 259
 260 theend_key:
 261         dma_unmap_single(ss->dev, rctx->p_key, op->keylen, DMA_TO_DEVICE);
 262
 263 theend:
 264
 265         return err;
 266 }
 267
 268 static int sun8i_ss_handle_cipher_request(struct crypto_engine *engine, void *areq)
 269 {
 270         int err;
 271         struct skcipher_request *breq = container_of(areq, struct skcipher_request, base);
 272
 273         err = sun8i_ss_cipher(breq);
 274         crypto_finalize_skcipher_request(engine, breq, err);
 275
 276         return 0;
 277 }
 278
 279 int sun8i_ss_skdecrypt(struct skcipher_request *areq)
 280 {
 281         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
 282         struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
 283         struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
 284         struct crypto_engine *engine;
 285         int e;
 286
 287         memset(rctx, 0, sizeof(struct sun8i_cipher_req_ctx));
 288         rctx->op_dir = SS_DECRYPTION;
 289
 290         if (sun8i_ss_need_fallback(areq))
 291                 return sun8i_ss_cipher_fallback(areq);
 292
 293         e = sun8i_ss_get_engine_number(op->ss);
 294         engine = op->ss->flows[e].engine;
 295         rctx->flow = e;
 296
 297         return crypto_transfer_skcipher_request_to_engine(engine, areq);
 298 }
 299
 300 int sun8i_ss_skencrypt(struct skcipher_request *areq)
 301 {
 302         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
 303         struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
 304         struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
 305         struct crypto_engine *engine;
 306         int e;
 307
 308         memset(rctx, 0, sizeof(struct sun8i_cipher_req_ctx));
 309         rctx->op_dir = SS_ENCRYPTION;
 310
 311         if (sun8i_ss_need_fallback(areq))
 312                 return sun8i_ss_cipher_fallback(areq);
 313
 314         e = sun8i_ss_get_engine_number(op->ss);
 315         engine = op->ss->flows[e].engine;
 316         rctx->flow = e;
 317
 318         return crypto_transfer_skcipher_request_to_engine(engine, areq);
 319 }
 320
 321 int sun8i_ss_cipher_init(struct crypto_tfm *tfm)
 322 {
 323         struct sun8i_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm);
 324         struct sun8i_ss_alg_template *algt;
 325         const char *name = crypto_tfm_alg_name(tfm);
 326         struct crypto_skcipher *sktfm = __crypto_skcipher_cast(tfm);
 327         struct skcipher_alg *alg = crypto_skcipher_alg(sktfm);
 328         int err;
 329
 330         memset(op, 0, sizeof(struct sun8i_cipher_tfm_ctx));
 331
 332         algt = container_of(alg, struct sun8i_ss_alg_template, alg.skcipher);
 333         op->ss = algt->ss;
 334
 335         op->fallback_tfm = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK);
 336         if (IS_ERR(op->fallback_tfm)) {
 337                 dev_err(op->ss->dev, "ERROR: Cannot allocate fallback for %s %ld\n",
 338                         name, PTR_ERR(op->fallback_tfm));
 339                 return PTR_ERR(op->fallback_tfm);
 340         }
 341
 342         sktfm->reqsize = sizeof(struct sun8i_cipher_req_ctx) +
 343                          crypto_skcipher_reqsize(op->fallback_tfm);
 344
 345
 346         dev_info(op->ss->dev, "Fallback for %s is %s\n",
 347                  crypto_tfm_alg_driver_name(&sktfm->base),
 348                  crypto_tfm_alg_driver_name(crypto_skcipher_tfm(op->fallback_tfm)));
 349
 350         op->enginectx.op.do_one_request = sun8i_ss_handle_cipher_request;
 351         op->enginectx.op.prepare_request = NULL;
 352         op->enginectx.op.unprepare_request = NULL;
 353
 354         err = pm_runtime_get_sync(op->ss->dev);
 355         if (err < 0) {
 356                 dev_err(op->ss->dev, "pm error %d\n", err);
 357                 goto error_pm;
 358         }
 359
 360         return 0;
 361 error_pm:
 362         crypto_free_skcipher(op->fallback_tfm);
 363         return err;
 364 }
 365
 366 void sun8i_ss_cipher_exit(struct crypto_tfm *tfm)
 367 {
 368         struct sun8i_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm);
 369
 370         kfree_sensitive(op->key);
 371         crypto_free_skcipher(op->fallback_tfm);
 372         pm_runtime_put_sync(op->ss->dev);
 373 }
 374
 375 int sun8i_ss_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
 376                         unsigned int keylen)
 377 {
 378         struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
 379         struct sun8i_ss_dev *ss = op->ss;
 380
 381         switch (keylen) {
 382         case 128 / 8:
 383                 break;
 384         case 192 / 8:
 385                 break;
 386         case 256 / 8:
 387                 break;
 388         default:
 389                 dev_dbg(ss->dev, "ERROR: Invalid keylen %u\n", keylen);
 390                 return -EINVAL;
 391         }
 392         kfree_sensitive(op->key);
 393         op->keylen = keylen;
 394         op->key = kmemdup(key, keylen, GFP_KERNEL | GFP_DMA);
 395         if (!op->key)
 396                 return -ENOMEM;
 397
 398         crypto_skcipher_clear_flags(op->fallback_tfm, CRYPTO_TFM_REQ_MASK);
 399         crypto_skcipher_set_flags(op->fallback_tfm, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
 400
 401         return crypto_skcipher_setkey(op->fallback_tfm, key, keylen);
 402 }
 403
 404 int sun8i_ss_des3_setkey(struct crypto_skcipher *tfm, const u8 *key,
 405                          unsigned int keylen)
 406 {
 407         struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
 408         struct sun8i_ss_dev *ss = op->ss;
 409
 410         if (unlikely(keylen != 3 * DES_KEY_SIZE)) {
 411                 dev_dbg(ss->dev, "Invalid keylen %u\n", keylen);
 412                 return -EINVAL;
 413         }
 414
 415         kfree_sensitive(op->key);
 416         op->keylen = keylen;
 417         op->key = kmemdup(key, keylen, GFP_KERNEL | GFP_DMA);
 418         if (!op->key)
 419                 return -ENOMEM;
 420
 421         crypto_skcipher_clear_flags(op->fallback_tfm, CRYPTO_TFM_REQ_MASK);
 422         crypto_skcipher_set_flags(op->fallback_tfm, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
 423
 424         return crypto_skcipher_setkey(op->fallback_tfm, key, keylen);
 425 }