drivers/tee/tee_core.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2015-2016, Linaro Limited
   4  */
   5
   6 #define pr_fmt(fmt) "%s: " fmt, __func__
   7
   8 #include <linux/cdev.h>
   9 #include <linux/cred.h>
  10 #include <linux/fs.h>
  11 #include <linux/idr.h>
  12 #include <linux/module.h>
  13 #include <linux/slab.h>
  14 #include <linux/tee_drv.h>
  15 #include <linux/uaccess.h>
  16 #include <crypto/hash.h>
  17 #include <crypto/sha.h>
  18 #include "tee_private.h"
  19
  20 #define TEE_NUM_DEVICES 32
  21
  22 #define TEE_IOCTL_PARAM_SIZE(x) (sizeof(struct tee_param) * (x))
  23
  24 #define TEE_UUID_NS_NAME_SIZE   128
  25
  26 /*
  27  * TEE Client UUID name space identifier (UUIDv4)
  28  *
  29  * Value here is random UUID that is allocated as name space identifier for
  30  * forming Client UUID's for TEE environment using UUIDv5 scheme.
  31  */
  32 static const uuid_t tee_client_uuid_ns = UUID_INIT(0x58ac9ca0, 0x2086, 0x4683,
  33                                                    0xa1, 0xb8, 0xec, 0x4b,
  34                                                    0xc0, 0x8e, 0x01, 0xb6);
  35
  36 /*
  37  * Unprivileged devices in the lower half range and privileged devices in
  38  * the upper half range.
  39  */
  40 static DECLARE_BITMAP(dev_mask, TEE_NUM_DEVICES);
  41 static DEFINE_SPINLOCK(driver_lock);
  42
  43 static struct class *tee_class;
  44 static dev_t tee_devt;
  45
  46 static struct tee_context *teedev_open(struct tee_device *teedev)
  47 {
  48         int rc;
  49         struct tee_context *ctx;
  50
  51         if (!tee_device_get(teedev))
  52                 return ERR_PTR(-EINVAL);
  53
  54         ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
  55         if (!ctx) {
  56                 rc = -ENOMEM;
  57                 goto err;
  58         }
  59
  60         kref_init(&ctx->refcount);
  61         ctx->teedev = teedev;
  62         rc = teedev->desc->ops->open(ctx);
  63         if (rc)
  64                 goto err;
  65
  66         return ctx;
  67 err:
  68         kfree(ctx);
  69         tee_device_put(teedev);
  70         return ERR_PTR(rc);
  71
  72 }
  73
  74 void teedev_ctx_get(struct tee_context *ctx)
  75 {
  76         if (ctx->releasing)
  77                 return;
  78
  79         kref_get(&ctx->refcount);
  80 }
  81
  82 static void teedev_ctx_release(struct kref *ref)
  83 {
  84         struct tee_context *ctx = container_of(ref, struct tee_context,
  85                                                refcount);
  86         ctx->releasing = true;
  87         ctx->teedev->desc->ops->release(ctx);
  88         kfree(ctx);
  89 }
  90
  91 void teedev_ctx_put(struct tee_context *ctx)
  92 {
  93         if (ctx->releasing)
  94                 return;
  95
  96         kref_put(&ctx->refcount, teedev_ctx_release);
  97 }
  98
  99 static void teedev_close_context(struct tee_context *ctx)
 100 {
 101         tee_device_put(ctx->teedev);
 102         teedev_ctx_put(ctx);
 103 }
 104
 105 static int tee_open(struct inode *inode, struct file *filp)
 106 {
 107         struct tee_context *ctx;
 108
 109         ctx = teedev_open(container_of(inode->i_cdev, struct tee_device, cdev));
 110         if (IS_ERR(ctx))
 111                 return PTR_ERR(ctx);
 112
 113         /*
 114          * Default user-space behaviour is to wait for tee-supplicant
 115          * if not present for any requests in this context.
 116          */
 117         ctx->supp_nowait = false;
 118         filp->private_data = ctx;
 119         return 0;
 120 }
 121
 122 static int tee_release(struct inode *inode, struct file *filp)
 123 {
 124         teedev_close_context(filp->private_data);
 125         return 0;
 126 }
 127
 128 /**
 129  * uuid_v5() - Calculate UUIDv5
 130  * @uuid: Resulting UUID
 131  * @ns: Name space ID for UUIDv5 function
 132  * @name: Name for UUIDv5 function
 133  * @size: Size of name
 134  *
 135  * UUIDv5 is specific in RFC 4122.
 136  *
 137  * This implements section (for SHA-1):
 138  * 4.3.  Algorithm for Creating a Name-Based UUID
 139  */
 140 static int uuid_v5(uuid_t *uuid, const uuid_t *ns, const void *name,
 141                    size_t size)
 142 {
 143         unsigned char hash[SHA1_DIGEST_SIZE];
 144         struct crypto_shash *shash = NULL;
 145         struct shash_desc *desc = NULL;
 146         int rc;
 147
 148         shash = crypto_alloc_shash("sha1", 0, 0);
 149         if (IS_ERR(shash)) {
 150                 rc = PTR_ERR(shash);
 151                 pr_err("shash(sha1) allocation failed\n");
 152                 return rc;
 153         }
 154
 155         desc = kzalloc(sizeof(*desc) + crypto_shash_descsize(shash),
 156                        GFP_KERNEL);
 157         if (!desc) {
 158                 rc = -ENOMEM;
 159                 goto out_free_shash;
 160         }
 161
 162         desc->tfm = shash;
 163
 164         rc = crypto_shash_init(desc);
 165         if (rc < 0)
 166                 goto out_free_desc;
 167
 168         rc = crypto_shash_update(desc, (const u8 *)ns, sizeof(*ns));
 169         if (rc < 0)
 170                 goto out_free_desc;
 171
 172         rc = crypto_shash_update(desc, (const u8 *)name, size);
 173         if (rc < 0)
 174                 goto out_free_desc;
 175
 176         rc = crypto_shash_final(desc, hash);
 177         if (rc < 0)
 178                 goto out_free_desc;
 179
 180         memcpy(uuid->b, hash, UUID_SIZE);
 181
 182         /* Tag for version 5 */
 183         uuid->b[6] = (hash[6] & 0x0F) | 0x50;
 184         uuid->b[8] = (hash[8] & 0x3F) | 0x80;
 185
 186 out_free_desc:
 187         kfree(desc);
 188
 189 out_free_shash:
 190         crypto_free_shash(shash);
 191         return rc;
 192 }
 193
 194 int tee_session_calc_client_uuid(uuid_t *uuid, u32 connection_method,
 195                                  const u8 connection_data[TEE_IOCTL_UUID_LEN])
 196 {
 197         gid_t ns_grp = (gid_t)-1;
 198         kgid_t grp = INVALID_GID;
 199         char *name = NULL;
 200         int name_len;
 201         int rc;
 202
 203         if (connection_method == TEE_IOCTL_LOGIN_PUBLIC ||
 204             connection_method == TEE_IOCTL_LOGIN_REE_KERNEL) {
 205                 /* Nil UUID to be passed to TEE environment */
 206                 uuid_copy(uuid, &uuid_null);
 207                 return 0;
 208         }
 209
 210         /*
 211          * In Linux environment client UUID is based on UUIDv5.
 212          *
 213          * Determine client UUID with following semantics for 'name':
 214          *
 215          * For TEEC_LOGIN_USER:
 216          * uid=<uid>
 217          *
 218          * For TEEC_LOGIN_GROUP:
 219          * gid=<gid>
 220          *
 221          */
 222
 223         name = kzalloc(TEE_UUID_NS_NAME_SIZE, GFP_KERNEL);
 224         if (!name)
 225                 return -ENOMEM;
 226
 227         switch (connection_method) {
 228         case TEE_IOCTL_LOGIN_USER:
 229                 name_len = snprintf(name, TEE_UUID_NS_NAME_SIZE, "uid=%x",
 230                                     current_euid().val);
 231                 if (name_len >= TEE_UUID_NS_NAME_SIZE) {
 232                         rc = -E2BIG;
 233                         goto out_free_name;
 234                 }
 235                 break;
 236
 237         case TEE_IOCTL_LOGIN_GROUP:
 238                 memcpy(&ns_grp, connection_data, sizeof(gid_t));
 239                 grp = make_kgid(current_user_ns(), ns_grp);
 240                 if (!gid_valid(grp) || !in_egroup_p(grp)) {
 241                         rc = -EPERM;
 242                         goto out_free_name;
 243                 }
 244
 245                 name_len = snprintf(name, TEE_UUID_NS_NAME_SIZE, "gid=%x",
 246                                     grp.val);
 247                 if (name_len >= TEE_UUID_NS_NAME_SIZE) {
 248                         rc = -E2BIG;
 249                         goto out_free_name;
 250                 }
 251                 break;
 252
 253         default:
 254                 rc = -EINVAL;
 255                 goto out_free_name;
 256         }
 257
 258         rc = uuid_v5(uuid, &tee_client_uuid_ns, name, name_len);
 259 out_free_name:
 260         kfree(name);
 261
 262         return rc;
 263 }
 264 EXPORT_SYMBOL_GPL(tee_session_calc_client_uuid);
 265
 266 static int tee_ioctl_version(struct tee_context *ctx,
 267                              struct tee_ioctl_version_data __user *uvers)
 268 {
 269         struct tee_ioctl_version_data vers;
 270
 271         ctx->teedev->desc->ops->get_version(ctx->teedev, &vers);
 272
 273         if (ctx->teedev->desc->flags & TEE_DESC_PRIVILEGED)
 274                 vers.gen_caps |= TEE_GEN_CAP_PRIVILEGED;
 275
 276         if (copy_to_user(uvers, &vers, sizeof(vers)))
 277                 return -EFAULT;
 278
 279         return 0;
 280 }
 281
 282 static int tee_ioctl_shm_alloc(struct tee_context *ctx,
 283                                struct tee_ioctl_shm_alloc_data __user *udata)
 284 {
 285         long ret;
 286         struct tee_ioctl_shm_alloc_data data;
 287         struct tee_shm *shm;
 288
 289         if (copy_from_user(&data, udata, sizeof(data)))
 290                 return -EFAULT;
 291
 292         /* Currently no input flags are supported */
 293         if (data.flags)
 294                 return -EINVAL;
 295
 296         shm = tee_shm_alloc(ctx, data.size, TEE_SHM_MAPPED | TEE_SHM_DMA_BUF);
 297         if (IS_ERR(shm))
 298                 return PTR_ERR(shm);
 299
 300         data.id = shm->id;
 301         data.flags = shm->flags;
 302         data.size = shm->size;
 303
 304         if (copy_to_user(udata, &data, sizeof(data)))
 305                 ret = -EFAULT;
 306         else
 307                 ret = tee_shm_get_fd(shm);
 308
 309         /*
 310          * When user space closes the file descriptor the shared memory
 311          * should be freed or if tee_shm_get_fd() failed then it will
 312          * be freed immediately.
 313          */
 314         tee_shm_put(shm);
 315         return ret;
 316 }
 317
 318 static int
 319 tee_ioctl_shm_register(struct tee_context *ctx,
 320                        struct tee_ioctl_shm_register_data __user *udata)
 321 {
 322         long ret;
 323         struct tee_ioctl_shm_register_data data;
 324         struct tee_shm *shm;
 325
 326         if (copy_from_user(&data, udata, sizeof(data)))
 327                 return -EFAULT;
 328
 329         /* Currently no input flags are supported */
 330         if (data.flags)
 331                 return -EINVAL;
 332
 333         shm = tee_shm_register(ctx, data.addr, data.length,
 334                                TEE_SHM_DMA_BUF | TEE_SHM_USER_MAPPED);
 335         if (IS_ERR(shm))
 336                 return PTR_ERR(shm);
 337
 338         data.id = shm->id;
 339         data.flags = shm->flags;
 340         data.length = shm->size;
 341
 342         if (copy_to_user(udata, &data, sizeof(data)))
 343                 ret = -EFAULT;
 344         else
 345                 ret = tee_shm_get_fd(shm);
 346         /*
 347          * When user space closes the file descriptor the shared memory
 348          * should be freed or if tee_shm_get_fd() failed then it will
 349          * be freed immediately.
 350          */
 351         tee_shm_put(shm);
 352         return ret;
 353 }
 354
 355 static int params_from_user(struct tee_context *ctx, struct tee_param *params,
 356                             size_t num_params,
 357                             struct tee_ioctl_param __user *uparams)
 358 {
 359         size_t n;
 360
 361         for (n = 0; n < num_params; n++) {
 362                 struct tee_shm *shm;
 363                 struct tee_ioctl_param ip;
 364
 365                 if (copy_from_user(&ip, uparams + n, sizeof(ip)))
 366                         return -EFAULT;
 367
 368                 /* All unused attribute bits has to be zero */
 369                 if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
 370                         return -EINVAL;
 371
 372                 params[n].attr = ip.attr;
 373                 switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
 374                 case TEE_IOCTL_PARAM_ATTR_TYPE_NONE:
 375                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
 376                         break;
 377                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
 378                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 379                         params[n].u.value.a = ip.a;
 380                         params[n].u.value.b = ip.b;
 381                         params[n].u.value.c = ip.c;
 382                         break;
 383                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
 384                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 385                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 386                         /*
 387                          * If a NULL pointer is passed to a TA in the TEE,
 388                          * the ip.c IOCTL parameters is set to TEE_MEMREF_NULL
 389                          * indicating a NULL memory reference.
 390                          */
 391                         if (ip.c != TEE_MEMREF_NULL) {
 392                                 /*
 393                                  * If we fail to get a pointer to a shared
 394                                  * memory object (and increase the ref count)
 395                                  * from an identifier we return an error. All
 396                                  * pointers that has been added in params have
 397                                  * an increased ref count. It's the callers
 398                                  * responibility to do tee_shm_put() on all
 399                                  * resolved pointers.
 400                                  */
 401                                 shm = tee_shm_get_from_id(ctx, ip.c);
 402                                 if (IS_ERR(shm))
 403                                         return PTR_ERR(shm);
 404
 405                                 /*
 406                                  * Ensure offset + size does not overflow
 407                                  * offset and does not overflow the size of
 408                                  * the referred shared memory object.
 409                                  */
 410                                 if ((ip.a + ip.b) < ip.a ||
 411                                     (ip.a + ip.b) > shm->size) {
 412                                         tee_shm_put(shm);
 413                                         return -EINVAL;
 414                                 }
 415                         } else if (ctx->cap_memref_null) {
 416                                 /* Pass NULL pointer to OP-TEE */
 417                                 shm = NULL;
 418                         } else {
 419                                 return -EINVAL;
 420                         }
 421
 422                         params[n].u.memref.shm_offs = ip.a;
 423                         params[n].u.memref.size = ip.b;
 424                         params[n].u.memref.shm = shm;
 425                         break;
 426                 default:
 427                         /* Unknown attribute */
 428                         return -EINVAL;
 429                 }
 430         }
 431         return 0;
 432 }
 433
 434 static int params_to_user(struct tee_ioctl_param __user *uparams,
 435                           size_t num_params, struct tee_param *params)
 436 {
 437         size_t n;
 438
 439         for (n = 0; n < num_params; n++) {
 440                 struct tee_ioctl_param __user *up = uparams + n;
 441                 struct tee_param *p = params + n;
 442
 443                 switch (p->attr) {
 444                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
 445                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 446                         if (put_user(p->u.value.a, &up->a) ||
 447                             put_user(p->u.value.b, &up->b) ||
 448                             put_user(p->u.value.c, &up->c))
 449                                 return -EFAULT;
 450                         break;
 451                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 452                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 453                         if (put_user((u64)p->u.memref.size, &up->b))
 454                                 return -EFAULT;
 455                 default:
 456                         break;
 457                 }
 458         }
 459         return 0;
 460 }
 461
 462 static int tee_ioctl_open_session(struct tee_context *ctx,
 463                                   struct tee_ioctl_buf_data __user *ubuf)
 464 {
 465         int rc;
 466         size_t n;
 467         struct tee_ioctl_buf_data buf;
 468         struct tee_ioctl_open_session_arg __user *uarg;
 469         struct tee_ioctl_open_session_arg arg;
 470         struct tee_ioctl_param __user *uparams = NULL;
 471         struct tee_param *params = NULL;
 472         bool have_session = false;
 473
 474         if (!ctx->teedev->desc->ops->open_session)
 475                 return -EINVAL;
 476
 477         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 478                 return -EFAULT;
 479
 480         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 481             buf.buf_len < sizeof(struct tee_ioctl_open_session_arg))
 482                 return -EINVAL;
 483
 484         uarg = u64_to_user_ptr(buf.buf_ptr);
 485         if (copy_from_user(&arg, uarg, sizeof(arg)))
 486                 return -EFAULT;
 487
 488         if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
 489                 return -EINVAL;
 490
 491         if (arg.num_params) {
 492                 params = kcalloc(arg.num_params, sizeof(struct tee_param),
 493                                  GFP_KERNEL);
 494                 if (!params)
 495                         return -ENOMEM;
 496                 uparams = uarg->params;
 497                 rc = params_from_user(ctx, params, arg.num_params, uparams);
 498                 if (rc)
 499                         goto out;
 500         }
 501
 502         if (arg.clnt_login >= TEE_IOCTL_LOGIN_REE_KERNEL_MIN &&
 503             arg.clnt_login <= TEE_IOCTL_LOGIN_REE_KERNEL_MAX) {
 504                 pr_debug("login method not allowed for user-space client\n");
 505                 rc = -EPERM;
 506                 goto out;
 507         }
 508
 509         rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params);
 510         if (rc)
 511                 goto out;
 512         have_session = true;
 513
 514         if (put_user(arg.session, &uarg->session) ||
 515             put_user(arg.ret, &uarg->ret) ||
 516             put_user(arg.ret_origin, &uarg->ret_origin)) {
 517                 rc = -EFAULT;
 518                 goto out;
 519         }
 520         rc = params_to_user(uparams, arg.num_params, params);
 521 out:
 522         /*
 523          * If we've succeeded to open the session but failed to communicate
 524          * it back to user space, close the session again to avoid leakage.
 525          */
 526         if (rc && have_session && ctx->teedev->desc->ops->close_session)
 527                 ctx->teedev->desc->ops->close_session(ctx, arg.session);
 528
 529         if (params) {
 530                 /* Decrease ref count for all valid shared memory pointers */
 531                 for (n = 0; n < arg.num_params; n++)
 532                         if (tee_param_is_memref(params + n) &&
 533                             params[n].u.memref.shm)
 534                                 tee_shm_put(params[n].u.memref.shm);
 535                 kfree(params);
 536         }
 537
 538         return rc;
 539 }
 540
 541 static int tee_ioctl_invoke(struct tee_context *ctx,
 542                             struct tee_ioctl_buf_data __user *ubuf)
 543 {
 544         int rc;
 545         size_t n;
 546         struct tee_ioctl_buf_data buf;
 547         struct tee_ioctl_invoke_arg __user *uarg;
 548         struct tee_ioctl_invoke_arg arg;
 549         struct tee_ioctl_param __user *uparams = NULL;
 550         struct tee_param *params = NULL;
 551
 552         if (!ctx->teedev->desc->ops->invoke_func)
 553                 return -EINVAL;
 554
 555         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 556                 return -EFAULT;
 557
 558         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 559             buf.buf_len < sizeof(struct tee_ioctl_invoke_arg))
 560                 return -EINVAL;
 561
 562         uarg = u64_to_user_ptr(buf.buf_ptr);
 563         if (copy_from_user(&arg, uarg, sizeof(arg)))
 564                 return -EFAULT;
 565
 566         if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
 567                 return -EINVAL;
 568
 569         if (arg.num_params) {
 570                 params = kcalloc(arg.num_params, sizeof(struct tee_param),
 571                                  GFP_KERNEL);
 572                 if (!params)
 573                         return -ENOMEM;
 574                 uparams = uarg->params;
 575                 rc = params_from_user(ctx, params, arg.num_params, uparams);
 576                 if (rc)
 577                         goto out;
 578         }
 579
 580         rc = ctx->teedev->desc->ops->invoke_func(ctx, &arg, params);
 581         if (rc)
 582                 goto out;
 583
 584         if (put_user(arg.ret, &uarg->ret) ||
 585             put_user(arg.ret_origin, &uarg->ret_origin)) {
 586                 rc = -EFAULT;
 587                 goto out;
 588         }
 589         rc = params_to_user(uparams, arg.num_params, params);
 590 out:
 591         if (params) {
 592                 /* Decrease ref count for all valid shared memory pointers */
 593                 for (n = 0; n < arg.num_params; n++)
 594                         if (tee_param_is_memref(params + n) &&
 595                             params[n].u.memref.shm)
 596                                 tee_shm_put(params[n].u.memref.shm);
 597                 kfree(params);
 598         }
 599         return rc;
 600 }
 601
 602 static int tee_ioctl_cancel(struct tee_context *ctx,
 603                             struct tee_ioctl_cancel_arg __user *uarg)
 604 {
 605         struct tee_ioctl_cancel_arg arg;
 606
 607         if (!ctx->teedev->desc->ops->cancel_req)
 608                 return -EINVAL;
 609
 610         if (copy_from_user(&arg, uarg, sizeof(arg)))
 611                 return -EFAULT;
 612
 613         return ctx->teedev->desc->ops->cancel_req(ctx, arg.cancel_id,
 614                                                   arg.session);
 615 }
 616
 617 static int
 618 tee_ioctl_close_session(struct tee_context *ctx,
 619                         struct tee_ioctl_close_session_arg __user *uarg)
 620 {
 621         struct tee_ioctl_close_session_arg arg;
 622
 623         if (!ctx->teedev->desc->ops->close_session)
 624                 return -EINVAL;
 625
 626         if (copy_from_user(&arg, uarg, sizeof(arg)))
 627                 return -EFAULT;
 628
 629         return ctx->teedev->desc->ops->close_session(ctx, arg.session);
 630 }
 631
 632 static int params_to_supp(struct tee_context *ctx,
 633                           struct tee_ioctl_param __user *uparams,
 634                           size_t num_params, struct tee_param *params)
 635 {
 636         size_t n;
 637
 638         for (n = 0; n < num_params; n++) {
 639                 struct tee_ioctl_param ip;
 640                 struct tee_param *p = params + n;
 641
 642                 ip.attr = p->attr;
 643                 switch (p->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
 644                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
 645                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 646                         ip.a = p->u.value.a;
 647                         ip.b = p->u.value.b;
 648                         ip.c = p->u.value.c;
 649                         break;
 650                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
 651                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 652                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 653                         ip.b = p->u.memref.size;
 654                         if (!p->u.memref.shm) {
 655                                 ip.a = 0;
 656                                 ip.c = (u64)-1; /* invalid shm id */
 657                                 break;
 658                         }
 659                         ip.a = p->u.memref.shm_offs;
 660                         ip.c = p->u.memref.shm->id;
 661                         break;
 662                 default:
 663                         ip.a = 0;
 664                         ip.b = 0;
 665                         ip.c = 0;
 666                         break;
 667                 }
 668
 669                 if (copy_to_user(uparams + n, &ip, sizeof(ip)))
 670                         return -EFAULT;
 671         }
 672
 673         return 0;
 674 }
 675
 676 static int tee_ioctl_supp_recv(struct tee_context *ctx,
 677                                struct tee_ioctl_buf_data __user *ubuf)
 678 {
 679         int rc;
 680         struct tee_ioctl_buf_data buf;
 681         struct tee_iocl_supp_recv_arg __user *uarg;
 682         struct tee_param *params;
 683         u32 num_params;
 684         u32 func;
 685
 686         if (!ctx->teedev->desc->ops->supp_recv)
 687                 return -EINVAL;
 688
 689         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 690                 return -EFAULT;
 691
 692         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 693             buf.buf_len < sizeof(struct tee_iocl_supp_recv_arg))
 694                 return -EINVAL;
 695
 696         uarg = u64_to_user_ptr(buf.buf_ptr);
 697         if (get_user(num_params, &uarg->num_params))
 698                 return -EFAULT;
 699
 700         if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) != buf.buf_len)
 701                 return -EINVAL;
 702
 703         params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
 704         if (!params)
 705                 return -ENOMEM;
 706
 707         rc = params_from_user(ctx, params, num_params, uarg->params);
 708         if (rc)
 709                 goto out;
 710
 711         rc = ctx->teedev->desc->ops->supp_recv(ctx, &func, &num_params, params);
 712         if (rc)
 713                 goto out;
 714
 715         if (put_user(func, &uarg->func) ||
 716             put_user(num_params, &uarg->num_params)) {
 717                 rc = -EFAULT;
 718                 goto out;
 719         }
 720
 721         rc = params_to_supp(ctx, uarg->params, num_params, params);
 722 out:
 723         kfree(params);
 724         return rc;
 725 }
 726
 727 static int params_from_supp(struct tee_param *params, size_t num_params,
 728                             struct tee_ioctl_param __user *uparams)
 729 {
 730         size_t n;
 731
 732         for (n = 0; n < num_params; n++) {
 733                 struct tee_param *p = params + n;
 734                 struct tee_ioctl_param ip;
 735
 736                 if (copy_from_user(&ip, uparams + n, sizeof(ip)))
 737                         return -EFAULT;
 738
 739                 /* All unused attribute bits has to be zero */
 740                 if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
 741                         return -EINVAL;
 742
 743                 p->attr = ip.attr;
 744                 switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
 745                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
 746                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 747                         /* Only out and in/out values can be updated */
 748                         p->u.value.a = ip.a;
 749                         p->u.value.b = ip.b;
 750                         p->u.value.c = ip.c;
 751                         break;
 752                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 753                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 754                         /*
 755                          * Only the size of the memref can be updated.
 756                          * Since we don't have access to the original
 757                          * parameters here, only store the supplied size.
 758                          * The driver will copy the updated size into the
 759                          * original parameters.
 760                          */
 761                         p->u.memref.shm = NULL;
 762                         p->u.memref.shm_offs = 0;
 763                         p->u.memref.size = ip.b;
 764                         break;
 765                 default:
 766                         memset(&p->u, 0, sizeof(p->u));
 767                         break;
 768                 }
 769         }
 770         return 0;
 771 }
 772
 773 static int tee_ioctl_supp_send(struct tee_context *ctx,
 774                                struct tee_ioctl_buf_data __user *ubuf)
 775 {
 776         long rc;
 777         struct tee_ioctl_buf_data buf;
 778         struct tee_iocl_supp_send_arg __user *uarg;
 779         struct tee_param *params;
 780         u32 num_params;
 781         u32 ret;
 782
 783         /* Not valid for this driver */
 784         if (!ctx->teedev->desc->ops->supp_send)
 785                 return -EINVAL;
 786
 787         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 788                 return -EFAULT;
 789
 790         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 791             buf.buf_len < sizeof(struct tee_iocl_supp_send_arg))
 792                 return -EINVAL;
 793
 794         uarg = u64_to_user_ptr(buf.buf_ptr);
 795         if (get_user(ret, &uarg->ret) ||
 796             get_user(num_params, &uarg->num_params))
 797                 return -EFAULT;
 798
 799         if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) > buf.buf_len)
 800                 return -EINVAL;
 801
 802         params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
 803         if (!params)
 804                 return -ENOMEM;
 805
 806         rc = params_from_supp(params, num_params, uarg->params);
 807         if (rc)
 808                 goto out;
 809
 810         rc = ctx->teedev->desc->ops->supp_send(ctx, ret, num_params, params);
 811 out:
 812         kfree(params);
 813         return rc;
 814 }
 815
 816 static long tee_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 817 {
 818         struct tee_context *ctx = filp->private_data;
 819         void __user *uarg = (void __user *)arg;
 820
 821         switch (cmd) {
 822         case TEE_IOC_VERSION:
 823                 return tee_ioctl_version(ctx, uarg);
 824         case TEE_IOC_SHM_ALLOC:
 825                 return tee_ioctl_shm_alloc(ctx, uarg);
 826         case TEE_IOC_SHM_REGISTER:
 827                 return tee_ioctl_shm_register(ctx, uarg);
 828         case TEE_IOC_OPEN_SESSION:
 829                 return tee_ioctl_open_session(ctx, uarg);
 830         case TEE_IOC_INVOKE:
 831                 return tee_ioctl_invoke(ctx, uarg);
 832         case TEE_IOC_CANCEL:
 833                 return tee_ioctl_cancel(ctx, uarg);
 834         case TEE_IOC_CLOSE_SESSION:
 835                 return tee_ioctl_close_session(ctx, uarg);
 836         case TEE_IOC_SUPPL_RECV:
 837                 return tee_ioctl_supp_recv(ctx, uarg);
 838         case TEE_IOC_SUPPL_SEND:
 839                 return tee_ioctl_supp_send(ctx, uarg);
 840         default:
 841                 return -EINVAL;
 842         }
 843 }
 844
 845 static const struct file_operations tee_fops = {
 846         .owner = THIS_MODULE,
 847         .open = tee_open,
 848         .release = tee_release,
 849         .unlocked_ioctl = tee_ioctl,
 850         .compat_ioctl = compat_ptr_ioctl,
 851 };
 852
 853 static void tee_release_device(struct device *dev)
 854 {
 855         struct tee_device *teedev = container_of(dev, struct tee_device, dev);
 856
 857         spin_lock(&driver_lock);
 858         clear_bit(teedev->id, dev_mask);
 859         spin_unlock(&driver_lock);
 860         mutex_destroy(&teedev->mutex);
 861         idr_destroy(&teedev->idr);
 862         kfree(teedev);
 863 }
 864
 865 /**
 866  * tee_device_alloc() - Allocate a new struct tee_device instance
 867  * @teedesc:    Descriptor for this driver
 868  * @dev:        Parent device for this device
 869  * @pool:       Shared memory pool, NULL if not used
 870  * @driver_data: Private driver data for this device
 871  *
 872  * Allocates a new struct tee_device instance. The device is
 873  * removed by tee_device_unregister().
 874  *
 875  * @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
 876  */
 877 struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
 878                                     struct device *dev,
 879                                     struct tee_shm_pool *pool,
 880                                     void *driver_data)
 881 {
 882         struct tee_device *teedev;
 883         void *ret;
 884         int rc, max_id;
 885         int offs = 0;
 886
 887         if (!teedesc || !teedesc->name || !teedesc->ops ||
 888             !teedesc->ops->get_version || !teedesc->ops->open ||
 889             !teedesc->ops->release || !pool)
 890                 return ERR_PTR(-EINVAL);
 891
 892         teedev = kzalloc(sizeof(*teedev), GFP_KERNEL);
 893         if (!teedev) {
 894                 ret = ERR_PTR(-ENOMEM);
 895                 goto err;
 896         }
 897
 898         max_id = TEE_NUM_DEVICES / 2;
 899
 900         if (teedesc->flags & TEE_DESC_PRIVILEGED) {
 901                 offs = TEE_NUM_DEVICES / 2;
 902                 max_id = TEE_NUM_DEVICES;
 903         }
 904
 905         spin_lock(&driver_lock);
 906         teedev->id = find_next_zero_bit(dev_mask, max_id, offs);
 907         if (teedev->id < max_id)
 908                 set_bit(teedev->id, dev_mask);
 909         spin_unlock(&driver_lock);
 910
 911         if (teedev->id >= max_id) {
 912                 ret = ERR_PTR(-ENOMEM);
 913                 goto err;
 914         }
 915
 916         snprintf(teedev->name, sizeof(teedev->name), "tee%s%d",
 917                  teedesc->flags & TEE_DESC_PRIVILEGED ? "priv" : "",
 918                  teedev->id - offs);
 919
 920         teedev->dev.class = tee_class;
 921         teedev->dev.release = tee_release_device;
 922         teedev->dev.parent = dev;
 923
 924         teedev->dev.devt = MKDEV(MAJOR(tee_devt), teedev->id);
 925
 926         rc = dev_set_name(&teedev->dev, "%s", teedev->name);
 927         if (rc) {
 928                 ret = ERR_PTR(rc);
 929                 goto err_devt;
 930         }
 931
 932         cdev_init(&teedev->cdev, &tee_fops);
 933         teedev->cdev.owner = teedesc->owner;
 934
 935         dev_set_drvdata(&teedev->dev, driver_data);
 936         device_initialize(&teedev->dev);
 937
 938         /* 1 as tee_device_unregister() does one final tee_device_put() */
 939         teedev->num_users = 1;
 940         init_completion(&teedev->c_no_users);
 941         mutex_init(&teedev->mutex);
 942         idr_init(&teedev->idr);
 943
 944         teedev->desc = teedesc;
 945         teedev->pool = pool;
 946
 947         return teedev;
 948 err_devt:
 949         unregister_chrdev_region(teedev->dev.devt, 1);
 950 err:
 951         pr_err("could not register %s driver\n",
 952                teedesc->flags & TEE_DESC_PRIVILEGED ? "privileged" : "client");
 953         if (teedev && teedev->id < TEE_NUM_DEVICES) {
 954                 spin_lock(&driver_lock);
 955                 clear_bit(teedev->id, dev_mask);
 956                 spin_unlock(&driver_lock);
 957         }
 958         kfree(teedev);
 959         return ret;
 960 }
 961 EXPORT_SYMBOL_GPL(tee_device_alloc);
 962
 963 static ssize_t implementation_id_show(struct device *dev,
 964                                       struct device_attribute *attr, char *buf)
 965 {
 966         struct tee_device *teedev = container_of(dev, struct tee_device, dev);
 967         struct tee_ioctl_version_data vers;
 968
 969         teedev->desc->ops->get_version(teedev, &vers);
 970         return scnprintf(buf, PAGE_SIZE, "%d\n", vers.impl_id);
 971 }
 972 static DEVICE_ATTR_RO(implementation_id);
 973
 974 static struct attribute *tee_dev_attrs[] = {
 975         &dev_attr_implementation_id.attr,
 976         NULL
 977 };
 978
 979 ATTRIBUTE_GROUPS(tee_dev);
 980
 981 /**
 982  * tee_device_register() - Registers a TEE device
 983  * @teedev:     Device to register
 984  *
 985  * tee_device_unregister() need to be called to remove the @teedev if
 986  * this function fails.
 987  *
 988  * @returns < 0 on failure
 989  */
 990 int tee_device_register(struct tee_device *teedev)
 991 {
 992         int rc;
 993
 994         if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
 995                 dev_err(&teedev->dev, "attempt to register twice\n");
 996                 return -EINVAL;
 997         }
 998
 999         teedev->dev.groups = tee_dev_groups;
1000
1001         rc = cdev_device_add(&teedev->cdev, &teedev->dev);
1002         if (rc) {
1003                 dev_err(&teedev->dev,
1004                         "unable to cdev_device_add() %s, major %d, minor %d, err=%d\n",
1005                         teedev->name, MAJOR(teedev->dev.devt),
1006                         MINOR(teedev->dev.devt), rc);
1007                 return rc;
1008         }
1009
1010         teedev->flags |= TEE_DEVICE_FLAG_REGISTERED;
1011         return 0;
1012 }
1013 EXPORT_SYMBOL_GPL(tee_device_register);
1014
1015 void tee_device_put(struct tee_device *teedev)
1016 {
1017         mutex_lock(&teedev->mutex);
1018         /* Shouldn't put in this state */
1019         if (!WARN_ON(!teedev->desc)) {
1020                 teedev->num_users--;
1021                 if (!teedev->num_users) {
1022                         teedev->desc = NULL;
1023                         complete(&teedev->c_no_users);
1024                 }
1025         }
1026         mutex_unlock(&teedev->mutex);
1027 }
1028
1029 bool tee_device_get(struct tee_device *teedev)
1030 {
1031         mutex_lock(&teedev->mutex);
1032         if (!teedev->desc) {
1033                 mutex_unlock(&teedev->mutex);
1034                 return false;
1035         }
1036         teedev->num_users++;
1037         mutex_unlock(&teedev->mutex);
1038         return true;
1039 }
1040
1041 /**
1042  * tee_device_unregister() - Removes a TEE device
1043  * @teedev:     Device to unregister
1044  *
1045  * This function should be called to remove the @teedev even if
1046  * tee_device_register() hasn't been called yet. Does nothing if
1047  * @teedev is NULL.
1048  */
1049 void tee_device_unregister(struct tee_device *teedev)
1050 {
1051         if (!teedev)
1052                 return;
1053
1054         if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED)
1055                 cdev_device_del(&teedev->cdev, &teedev->dev);
1056
1057         tee_device_put(teedev);
1058         wait_for_completion(&teedev->c_no_users);
1059
1060         /*
1061          * No need to take a mutex any longer now since teedev->desc was
1062          * set to NULL before teedev->c_no_users was completed.
1063          */
1064
1065         teedev->pool = NULL;
1066
1067         put_device(&teedev->dev);
1068 }
1069 EXPORT_SYMBOL_GPL(tee_device_unregister);
1070
1071 /**
1072  * tee_get_drvdata() - Return driver_data pointer
1073  * @teedev:     Device containing the driver_data pointer
1074  * @returns the driver_data pointer supplied to tee_register().
1075  */
1076 void *tee_get_drvdata(struct tee_device *teedev)
1077 {
1078         return dev_get_drvdata(&teedev->dev);
1079 }
1080 EXPORT_SYMBOL_GPL(tee_get_drvdata);
1081
1082 struct match_dev_data {
1083         struct tee_ioctl_version_data *vers;
1084         const void *data;
1085         int (*match)(struct tee_ioctl_version_data *, const void *);
1086 };
1087
1088 static int match_dev(struct device *dev, const void *data)
1089 {
1090         const struct match_dev_data *match_data = data;
1091         struct tee_device *teedev = container_of(dev, struct tee_device, dev);
1092
1093         teedev->desc->ops->get_version(teedev, match_data->vers);
1094         return match_data->match(match_data->vers, match_data->data);
1095 }
1096
1097 struct tee_context *
1098 tee_client_open_context(struct tee_context *start,
1099                         int (*match)(struct tee_ioctl_version_data *,
1100                                      const void *),
1101                         const void *data, struct tee_ioctl_version_data *vers)
1102 {
1103         struct device *dev = NULL;
1104         struct device *put_dev = NULL;
1105         struct tee_context *ctx = NULL;
1106         struct tee_ioctl_version_data v;
1107         struct match_dev_data match_data = { vers ? vers : &v, data, match };
1108
1109         if (start)
1110                 dev = &start->teedev->dev;
1111
1112         do {
1113                 dev = class_find_device(tee_class, dev, &match_data, match_dev);
1114                 if (!dev) {
1115                         ctx = ERR_PTR(-ENOENT);
1116                         break;
1117                 }
1118
1119                 put_device(put_dev);
1120                 put_dev = dev;
1121
1122                 ctx = teedev_open(container_of(dev, struct tee_device, dev));
1123         } while (IS_ERR(ctx) && PTR_ERR(ctx) != -ENOMEM);
1124
1125         put_device(put_dev);
1126         /*
1127          * Default behaviour for in kernel client is to not wait for
1128          * tee-supplicant if not present for any requests in this context.
1129          * Also this flag could be configured again before call to
1130          * tee_client_open_session() if any in kernel client requires
1131          * different behaviour.
1132          */
1133         if (!IS_ERR(ctx))
1134                 ctx->supp_nowait = true;
1135
1136         return ctx;
1137 }
1138 EXPORT_SYMBOL_GPL(tee_client_open_context);
1139
1140 void tee_client_close_context(struct tee_context *ctx)
1141 {
1142         teedev_close_context(ctx);
1143 }
1144 EXPORT_SYMBOL_GPL(tee_client_close_context);
1145
1146 void tee_client_get_version(struct tee_context *ctx,
1147                             struct tee_ioctl_version_data *vers)
1148 {
1149         ctx->teedev->desc->ops->get_version(ctx->teedev, vers);
1150 }
1151 EXPORT_SYMBOL_GPL(tee_client_get_version);
1152
1153 int tee_client_open_session(struct tee_context *ctx,
1154                             struct tee_ioctl_open_session_arg *arg,
1155                             struct tee_param *param)
1156 {
1157         if (!ctx->teedev->desc->ops->open_session)
1158                 return -EINVAL;
1159         return ctx->teedev->desc->ops->open_session(ctx, arg, param);
1160 }
1161 EXPORT_SYMBOL_GPL(tee_client_open_session);
1162
1163 int tee_client_close_session(struct tee_context *ctx, u32 session)
1164 {
1165         if (!ctx->teedev->desc->ops->close_session)
1166                 return -EINVAL;
1167         return ctx->teedev->desc->ops->close_session(ctx, session);
1168 }
1169 EXPORT_SYMBOL_GPL(tee_client_close_session);
1170
1171 int tee_client_invoke_func(struct tee_context *ctx,
1172                            struct tee_ioctl_invoke_arg *arg,
1173                            struct tee_param *param)
1174 {
1175         if (!ctx->teedev->desc->ops->invoke_func)
1176                 return -EINVAL;
1177         return ctx->teedev->desc->ops->invoke_func(ctx, arg, param);
1178 }
1179 EXPORT_SYMBOL_GPL(tee_client_invoke_func);
1180
1181 int tee_client_cancel_req(struct tee_context *ctx,
1182                           struct tee_ioctl_cancel_arg *arg)
1183 {
1184         if (!ctx->teedev->desc->ops->cancel_req)
1185                 return -EINVAL;
1186         return ctx->teedev->desc->ops->cancel_req(ctx, arg->cancel_id,
1187                                                   arg->session);
1188 }
1189
1190 static int tee_client_device_match(struct device *dev,
1191                                    struct device_driver *drv)
1192 {
1193         const struct tee_client_device_id *id_table;
1194         struct tee_client_device *tee_device;
1195
1196         id_table = to_tee_client_driver(drv)->id_table;
1197         tee_device = to_tee_client_device(dev);
1198
1199         while (!uuid_is_null(&id_table->uuid)) {
1200                 if (uuid_equal(&tee_device->id.uuid, &id_table->uuid))
1201                         return 1;
1202                 id_table++;
1203         }
1204
1205         return 0;
1206 }
1207
1208 static int tee_client_device_uevent(struct device *dev,
1209                                     struct kobj_uevent_env *env)
1210 {
1211         uuid_t *dev_id = &to_tee_client_device(dev)->id.uuid;
1212
1213         return add_uevent_var(env, "MODALIAS=tee:%pUb", dev_id);
1214 }
1215
1216 struct bus_type tee_bus_type = {
1217         .name           = "tee",
1218         .match          = tee_client_device_match,
1219         .uevent         = tee_client_device_uevent,
1220 };
1221 EXPORT_SYMBOL_GPL(tee_bus_type);
1222
1223 static int __init tee_init(void)
1224 {
1225         int rc;
1226
1227         tee_class = class_create(THIS_MODULE, "tee");
1228         if (IS_ERR(tee_class)) {
1229                 pr_err("couldn't create class\n");
1230                 return PTR_ERR(tee_class);
1231         }
1232
1233         rc = alloc_chrdev_region(&tee_devt, 0, TEE_NUM_DEVICES, "tee");
1234         if (rc) {
1235                 pr_err("failed to allocate char dev region\n");
1236                 goto out_unreg_class;
1237         }
1238
1239         rc = bus_register(&tee_bus_type);
1240         if (rc) {
1241                 pr_err("failed to register tee bus\n");
1242                 goto out_unreg_chrdev;
1243         }
1244
1245         return 0;
1246
1247 out_unreg_chrdev:
1248         unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1249 out_unreg_class:
1250         class_destroy(tee_class);
1251         tee_class = NULL;
1252
1253         return rc;
1254 }
1255
1256 static void __exit tee_exit(void)
1257 {
1258         bus_unregister(&tee_bus_type);
1259         unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1260         class_destroy(tee_class);
1261         tee_class = NULL;
1262 }
1263
1264 subsys_initcall(tee_init);
1265 module_exit(tee_exit);
1266
1267 MODULE_AUTHOR("Linaro");
1268 MODULE_DESCRIPTION("TEE Driver");
1269 MODULE_VERSION("1.0");
1270 MODULE_LICENSE("GPL v2");