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/sha1.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 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 EXPORT_SYMBOL_GPL(teedev_open);
  74
  75 void teedev_ctx_get(struct tee_context *ctx)
  76 {
  77         if (ctx->releasing)
  78                 return;
  79
  80         kref_get(&ctx->refcount);
  81 }
  82
  83 static void teedev_ctx_release(struct kref *ref)
  84 {
  85         struct tee_context *ctx = container_of(ref, struct tee_context,
  86                                                refcount);
  87         ctx->releasing = true;
  88         ctx->teedev->desc->ops->release(ctx);
  89         kfree(ctx);
  90 }
  91
  92 void teedev_ctx_put(struct tee_context *ctx)
  93 {
  94         if (ctx->releasing)
  95                 return;
  96
  97         kref_put(&ctx->refcount, teedev_ctx_release);
  98 }
  99
 100 void teedev_close_context(struct tee_context *ctx)
 101 {
 102         struct tee_device *teedev = ctx->teedev;
 103
 104         teedev_ctx_put(ctx);
 105         tee_device_put(teedev);
 106 }
 107 EXPORT_SYMBOL_GPL(teedev_close_context);
 108
 109 static int tee_open(struct inode *inode, struct file *filp)
 110 {
 111         struct tee_context *ctx;
 112
 113         ctx = teedev_open(container_of(inode->i_cdev, struct tee_device, cdev));
 114         if (IS_ERR(ctx))
 115                 return PTR_ERR(ctx);
 116
 117         /*
 118          * Default user-space behaviour is to wait for tee-supplicant
 119          * if not present for any requests in this context.
 120          */
 121         ctx->supp_nowait = false;
 122         filp->private_data = ctx;
 123         return 0;
 124 }
 125
 126 static int tee_release(struct inode *inode, struct file *filp)
 127 {
 128         teedev_close_context(filp->private_data);
 129         return 0;
 130 }
 131
 132 /**
 133  * uuid_v5() - Calculate UUIDv5
 134  * @uuid: Resulting UUID
 135  * @ns: Name space ID for UUIDv5 function
 136  * @name: Name for UUIDv5 function
 137  * @size: Size of name
 138  *
 139  * UUIDv5 is specific in RFC 4122.
 140  *
 141  * This implements section (for SHA-1):
 142  * 4.3.  Algorithm for Creating a Name-Based UUID
 143  */
 144 static int uuid_v5(uuid_t *uuid, const uuid_t *ns, const void *name,
 145                    size_t size)
 146 {
 147         unsigned char hash[SHA1_DIGEST_SIZE];
 148         struct crypto_shash *shash = NULL;
 149         struct shash_desc *desc = NULL;
 150         int rc;
 151
 152         shash = crypto_alloc_shash("sha1", 0, 0);
 153         if (IS_ERR(shash)) {
 154                 rc = PTR_ERR(shash);
 155                 pr_err("shash(sha1) allocation failed\n");
 156                 return rc;
 157         }
 158
 159         desc = kzalloc(sizeof(*desc) + crypto_shash_descsize(shash),
 160                        GFP_KERNEL);
 161         if (!desc) {
 162                 rc = -ENOMEM;
 163                 goto out_free_shash;
 164         }
 165
 166         desc->tfm = shash;
 167
 168         rc = crypto_shash_init(desc);
 169         if (rc < 0)
 170                 goto out_free_desc;
 171
 172         rc = crypto_shash_update(desc, (const u8 *)ns, sizeof(*ns));
 173         if (rc < 0)
 174                 goto out_free_desc;
 175
 176         rc = crypto_shash_update(desc, (const u8 *)name, size);
 177         if (rc < 0)
 178                 goto out_free_desc;
 179
 180         rc = crypto_shash_final(desc, hash);
 181         if (rc < 0)
 182                 goto out_free_desc;
 183
 184         memcpy(uuid->b, hash, UUID_SIZE);
 185
 186         /* Tag for version 5 */
 187         uuid->b[6] = (hash[6] & 0x0F) | 0x50;
 188         uuid->b[8] = (hash[8] & 0x3F) | 0x80;
 189
 190 out_free_desc:
 191         kfree(desc);
 192
 193 out_free_shash:
 194         crypto_free_shash(shash);
 195         return rc;
 196 }
 197
 198 int tee_session_calc_client_uuid(uuid_t *uuid, u32 connection_method,
 199                                  const u8 connection_data[TEE_IOCTL_UUID_LEN])
 200 {
 201         gid_t ns_grp = (gid_t)-1;
 202         kgid_t grp = INVALID_GID;
 203         char *name = NULL;
 204         int name_len;
 205         int rc;
 206
 207         if (connection_method == TEE_IOCTL_LOGIN_PUBLIC ||
 208             connection_method == TEE_IOCTL_LOGIN_REE_KERNEL) {
 209                 /* Nil UUID to be passed to TEE environment */
 210                 uuid_copy(uuid, &uuid_null);
 211                 return 0;
 212         }
 213
 214         /*
 215          * In Linux environment client UUID is based on UUIDv5.
 216          *
 217          * Determine client UUID with following semantics for 'name':
 218          *
 219          * For TEEC_LOGIN_USER:
 220          * uid=<uid>
 221          *
 222          * For TEEC_LOGIN_GROUP:
 223          * gid=<gid>
 224          *
 225          */
 226
 227         name = kzalloc(TEE_UUID_NS_NAME_SIZE, GFP_KERNEL);
 228         if (!name)
 229                 return -ENOMEM;
 230
 231         switch (connection_method) {
 232         case TEE_IOCTL_LOGIN_USER:
 233                 name_len = snprintf(name, TEE_UUID_NS_NAME_SIZE, "uid=%x",
 234                                     current_euid().val);
 235                 if (name_len >= TEE_UUID_NS_NAME_SIZE) {
 236                         rc = -E2BIG;
 237                         goto out_free_name;
 238                 }
 239                 break;
 240
 241         case TEE_IOCTL_LOGIN_GROUP:
 242                 memcpy(&ns_grp, connection_data, sizeof(gid_t));
 243                 grp = make_kgid(current_user_ns(), ns_grp);
 244                 if (!gid_valid(grp) || !in_egroup_p(grp)) {
 245                         rc = -EPERM;
 246                         goto out_free_name;
 247                 }
 248
 249                 name_len = snprintf(name, TEE_UUID_NS_NAME_SIZE, "gid=%x",
 250                                     grp.val);
 251                 if (name_len >= TEE_UUID_NS_NAME_SIZE) {
 252                         rc = -E2BIG;
 253                         goto out_free_name;
 254                 }
 255                 break;
 256
 257         default:
 258                 rc = -EINVAL;
 259                 goto out_free_name;
 260         }
 261
 262         rc = uuid_v5(uuid, &tee_client_uuid_ns, name, name_len);
 263 out_free_name:
 264         kfree(name);
 265
 266         return rc;
 267 }
 268 EXPORT_SYMBOL_GPL(tee_session_calc_client_uuid);
 269
 270 static int tee_ioctl_version(struct tee_context *ctx,
 271                              struct tee_ioctl_version_data __user *uvers)
 272 {
 273         struct tee_ioctl_version_data vers;
 274
 275         ctx->teedev->desc->ops->get_version(ctx->teedev, &vers);
 276
 277         if (ctx->teedev->desc->flags & TEE_DESC_PRIVILEGED)
 278                 vers.gen_caps |= TEE_GEN_CAP_PRIVILEGED;
 279
 280         if (copy_to_user(uvers, &vers, sizeof(vers)))
 281                 return -EFAULT;
 282
 283         return 0;
 284 }
 285
 286 static int tee_ioctl_shm_alloc(struct tee_context *ctx,
 287                                struct tee_ioctl_shm_alloc_data __user *udata)
 288 {
 289         long ret;
 290         struct tee_ioctl_shm_alloc_data data;
 291         struct tee_shm *shm;
 292
 293         if (copy_from_user(&data, udata, sizeof(data)))
 294                 return -EFAULT;
 295
 296         /* Currently no input flags are supported */
 297         if (data.flags)
 298                 return -EINVAL;
 299
 300         shm = tee_shm_alloc_user_buf(ctx, data.size);
 301         if (IS_ERR(shm))
 302                 return PTR_ERR(shm);
 303
 304         data.id = shm->id;
 305         data.size = shm->size;
 306
 307         if (copy_to_user(udata, &data, sizeof(data)))
 308                 ret = -EFAULT;
 309         else
 310                 ret = tee_shm_get_fd(shm);
 311
 312         /*
 313          * When user space closes the file descriptor the shared memory
 314          * should be freed or if tee_shm_get_fd() failed then it will
 315          * be freed immediately.
 316          */
 317         tee_shm_put(shm);
 318         return ret;
 319 }
 320
 321 static int
 322 tee_ioctl_shm_register(struct tee_context *ctx,
 323                        struct tee_ioctl_shm_register_data __user *udata)
 324 {
 325         long ret;
 326         struct tee_ioctl_shm_register_data data;
 327         struct tee_shm *shm;
 328
 329         if (copy_from_user(&data, udata, sizeof(data)))
 330                 return -EFAULT;
 331
 332         /* Currently no input flags are supported */
 333         if (data.flags)
 334                 return -EINVAL;
 335
 336         shm = tee_shm_register_user_buf(ctx, data.addr, data.length);
 337         if (IS_ERR(shm))
 338                 return PTR_ERR(shm);
 339
 340         data.id = shm->id;
 341         data.length = shm->size;
 342
 343         if (copy_to_user(udata, &data, sizeof(data)))
 344                 ret = -EFAULT;
 345         else
 346                 ret = tee_shm_get_fd(shm);
 347         /*
 348          * When user space closes the file descriptor the shared memory
 349          * should be freed or if tee_shm_get_fd() failed then it will
 350          * be freed immediately.
 351          */
 352         tee_shm_put(shm);
 353         return ret;
 354 }
 355
 356 static int params_from_user(struct tee_context *ctx, struct tee_param *params,
 357                             size_t num_params,
 358                             struct tee_ioctl_param __user *uparams)
 359 {
 360         size_t n;
 361
 362         for (n = 0; n < num_params; n++) {
 363                 struct tee_shm *shm;
 364                 struct tee_ioctl_param ip;
 365
 366                 if (copy_from_user(&ip, uparams + n, sizeof(ip)))
 367                         return -EFAULT;
 368
 369                 /* All unused attribute bits has to be zero */
 370                 if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
 371                         return -EINVAL;
 372
 373                 params[n].attr = ip.attr;
 374                 switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
 375                 case TEE_IOCTL_PARAM_ATTR_TYPE_NONE:
 376                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
 377                         break;
 378                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
 379                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 380                         params[n].u.value.a = ip.a;
 381                         params[n].u.value.b = ip.b;
 382                         params[n].u.value.c = ip.c;
 383                         break;
 384                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
 385                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 386                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 387                         /*
 388                          * If a NULL pointer is passed to a TA in the TEE,
 389                          * the ip.c IOCTL parameters is set to TEE_MEMREF_NULL
 390                          * indicating a NULL memory reference.
 391                          */
 392                         if (ip.c != TEE_MEMREF_NULL) {
 393                                 /*
 394                                  * If we fail to get a pointer to a shared
 395                                  * memory object (and increase the ref count)
 396                                  * from an identifier we return an error. All
 397                                  * pointers that has been added in params have
 398                                  * an increased ref count. It's the callers
 399                                  * responibility to do tee_shm_put() on all
 400                                  * resolved pointers.
 401                                  */
 402                                 shm = tee_shm_get_from_id(ctx, ip.c);
 403                                 if (IS_ERR(shm))
 404                                         return PTR_ERR(shm);
 405
 406                                 /*
 407                                  * Ensure offset + size does not overflow
 408                                  * offset and does not overflow the size of
 409                                  * the referred shared memory object.
 410                                  */
 411                                 if ((ip.a + ip.b) < ip.a ||
 412                                     (ip.a + ip.b) > shm->size) {
 413                                         tee_shm_put(shm);
 414                                         return -EINVAL;
 415                                 }
 416                         } else if (ctx->cap_memref_null) {
 417                                 /* Pass NULL pointer to OP-TEE */
 418                                 shm = NULL;
 419                         } else {
 420                                 return -EINVAL;
 421                         }
 422
 423                         params[n].u.memref.shm_offs = ip.a;
 424                         params[n].u.memref.size = ip.b;
 425                         params[n].u.memref.shm = shm;
 426                         break;
 427                 default:
 428                         /* Unknown attribute */
 429                         return -EINVAL;
 430                 }
 431         }
 432         return 0;
 433 }
 434
 435 static int params_to_user(struct tee_ioctl_param __user *uparams,
 436                           size_t num_params, struct tee_param *params)
 437 {
 438         size_t n;
 439
 440         for (n = 0; n < num_params; n++) {
 441                 struct tee_ioctl_param __user *up = uparams + n;
 442                 struct tee_param *p = params + n;
 443
 444                 switch (p->attr) {
 445                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
 446                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 447                         if (put_user(p->u.value.a, &up->a) ||
 448                             put_user(p->u.value.b, &up->b) ||
 449                             put_user(p->u.value.c, &up->c))
 450                                 return -EFAULT;
 451                         break;
 452                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 453                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 454                         if (put_user((u64)p->u.memref.size, &up->b))
 455                                 return -EFAULT;
 456                         break;
 457                 default:
 458                         break;
 459                 }
 460         }
 461         return 0;
 462 }
 463
 464 static int tee_ioctl_open_session(struct tee_context *ctx,
 465                                   struct tee_ioctl_buf_data __user *ubuf)
 466 {
 467         int rc;
 468         size_t n;
 469         struct tee_ioctl_buf_data buf;
 470         struct tee_ioctl_open_session_arg __user *uarg;
 471         struct tee_ioctl_open_session_arg arg;
 472         struct tee_ioctl_param __user *uparams = NULL;
 473         struct tee_param *params = NULL;
 474         bool have_session = false;
 475
 476         if (!ctx->teedev->desc->ops->open_session)
 477                 return -EINVAL;
 478
 479         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 480                 return -EFAULT;
 481
 482         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 483             buf.buf_len < sizeof(struct tee_ioctl_open_session_arg))
 484                 return -EINVAL;
 485
 486         uarg = u64_to_user_ptr(buf.buf_ptr);
 487         if (copy_from_user(&arg, uarg, sizeof(arg)))
 488                 return -EFAULT;
 489
 490         if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
 491                 return -EINVAL;
 492
 493         if (arg.num_params) {
 494                 params = kcalloc(arg.num_params, sizeof(struct tee_param),
 495                                  GFP_KERNEL);
 496                 if (!params)
 497                         return -ENOMEM;
 498                 uparams = uarg->params;
 499                 rc = params_from_user(ctx, params, arg.num_params, uparams);
 500                 if (rc)
 501                         goto out;
 502         }
 503
 504         if (arg.clnt_login >= TEE_IOCTL_LOGIN_REE_KERNEL_MIN &&
 505             arg.clnt_login <= TEE_IOCTL_LOGIN_REE_KERNEL_MAX) {
 506                 pr_debug("login method not allowed for user-space client\n");
 507                 rc = -EPERM;
 508                 goto out;
 509         }
 510
 511         rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params);
 512         if (rc)
 513                 goto out;
 514         have_session = true;
 515
 516         if (put_user(arg.session, &uarg->session) ||
 517             put_user(arg.ret, &uarg->ret) ||
 518             put_user(arg.ret_origin, &uarg->ret_origin)) {
 519                 rc = -EFAULT;
 520                 goto out;
 521         }
 522         rc = params_to_user(uparams, arg.num_params, params);
 523 out:
 524         /*
 525          * If we've succeeded to open the session but failed to communicate
 526          * it back to user space, close the session again to avoid leakage.
 527          */
 528         if (rc && have_session && ctx->teedev->desc->ops->close_session)
 529                 ctx->teedev->desc->ops->close_session(ctx, arg.session);
 530
 531         if (params) {
 532                 /* Decrease ref count for all valid shared memory pointers */
 533                 for (n = 0; n < arg.num_params; n++)
 534                         if (tee_param_is_memref(params + n) &&
 535                             params[n].u.memref.shm)
 536                                 tee_shm_put(params[n].u.memref.shm);
 537                 kfree(params);
 538         }
 539
 540         return rc;
 541 }
 542
 543 static int tee_ioctl_invoke(struct tee_context *ctx,
 544                             struct tee_ioctl_buf_data __user *ubuf)
 545 {
 546         int rc;
 547         size_t n;
 548         struct tee_ioctl_buf_data buf;
 549         struct tee_ioctl_invoke_arg __user *uarg;
 550         struct tee_ioctl_invoke_arg arg;
 551         struct tee_ioctl_param __user *uparams = NULL;
 552         struct tee_param *params = NULL;
 553
 554         if (!ctx->teedev->desc->ops->invoke_func)
 555                 return -EINVAL;
 556
 557         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 558                 return -EFAULT;
 559
 560         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 561             buf.buf_len < sizeof(struct tee_ioctl_invoke_arg))
 562                 return -EINVAL;
 563
 564         uarg = u64_to_user_ptr(buf.buf_ptr);
 565         if (copy_from_user(&arg, uarg, sizeof(arg)))
 566                 return -EFAULT;
 567
 568         if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
 569                 return -EINVAL;
 570
 571         if (arg.num_params) {
 572                 params = kcalloc(arg.num_params, sizeof(struct tee_param),
 573                                  GFP_KERNEL);
 574                 if (!params)
 575                         return -ENOMEM;
 576                 uparams = uarg->params;
 577                 rc = params_from_user(ctx, params, arg.num_params, uparams);
 578                 if (rc)
 579                         goto out;
 580         }
 581
 582         rc = ctx->teedev->desc->ops->invoke_func(ctx, &arg, params);
 583         if (rc)
 584                 goto out;
 585
 586         if (put_user(arg.ret, &uarg->ret) ||
 587             put_user(arg.ret_origin, &uarg->ret_origin)) {
 588                 rc = -EFAULT;
 589                 goto out;
 590         }
 591         rc = params_to_user(uparams, arg.num_params, params);
 592 out:
 593         if (params) {
 594                 /* Decrease ref count for all valid shared memory pointers */
 595                 for (n = 0; n < arg.num_params; n++)
 596                         if (tee_param_is_memref(params + n) &&
 597                             params[n].u.memref.shm)
 598                                 tee_shm_put(params[n].u.memref.shm);
 599                 kfree(params);
 600         }
 601         return rc;
 602 }
 603
 604 static int tee_ioctl_cancel(struct tee_context *ctx,
 605                             struct tee_ioctl_cancel_arg __user *uarg)
 606 {
 607         struct tee_ioctl_cancel_arg arg;
 608
 609         if (!ctx->teedev->desc->ops->cancel_req)
 610                 return -EINVAL;
 611
 612         if (copy_from_user(&arg, uarg, sizeof(arg)))
 613                 return -EFAULT;
 614
 615         return ctx->teedev->desc->ops->cancel_req(ctx, arg.cancel_id,
 616                                                   arg.session);
 617 }
 618
 619 static int
 620 tee_ioctl_close_session(struct tee_context *ctx,
 621                         struct tee_ioctl_close_session_arg __user *uarg)
 622 {
 623         struct tee_ioctl_close_session_arg arg;
 624
 625         if (!ctx->teedev->desc->ops->close_session)
 626                 return -EINVAL;
 627
 628         if (copy_from_user(&arg, uarg, sizeof(arg)))
 629                 return -EFAULT;
 630
 631         return ctx->teedev->desc->ops->close_session(ctx, arg.session);
 632 }
 633
 634 static int params_to_supp(struct tee_context *ctx,
 635                           struct tee_ioctl_param __user *uparams,
 636                           size_t num_params, struct tee_param *params)
 637 {
 638         size_t n;
 639
 640         for (n = 0; n < num_params; n++) {
 641                 struct tee_ioctl_param ip;
 642                 struct tee_param *p = params + n;
 643
 644                 ip.attr = p->attr;
 645                 switch (p->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
 646                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
 647                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 648                         ip.a = p->u.value.a;
 649                         ip.b = p->u.value.b;
 650                         ip.c = p->u.value.c;
 651                         break;
 652                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
 653                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 654                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 655                         ip.b = p->u.memref.size;
 656                         if (!p->u.memref.shm) {
 657                                 ip.a = 0;
 658                                 ip.c = (u64)-1; /* invalid shm id */
 659                                 break;
 660                         }
 661                         ip.a = p->u.memref.shm_offs;
 662                         ip.c = p->u.memref.shm->id;
 663                         break;
 664                 default:
 665                         ip.a = 0;
 666                         ip.b = 0;
 667                         ip.c = 0;
 668                         break;
 669                 }
 670
 671                 if (copy_to_user(uparams + n, &ip, sizeof(ip)))
 672                         return -EFAULT;
 673         }
 674
 675         return 0;
 676 }
 677
 678 static int tee_ioctl_supp_recv(struct tee_context *ctx,
 679                                struct tee_ioctl_buf_data __user *ubuf)
 680 {
 681         int rc;
 682         struct tee_ioctl_buf_data buf;
 683         struct tee_iocl_supp_recv_arg __user *uarg;
 684         struct tee_param *params;
 685         u32 num_params;
 686         u32 func;
 687
 688         if (!ctx->teedev->desc->ops->supp_recv)
 689                 return -EINVAL;
 690
 691         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 692                 return -EFAULT;
 693
 694         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 695             buf.buf_len < sizeof(struct tee_iocl_supp_recv_arg))
 696                 return -EINVAL;
 697
 698         uarg = u64_to_user_ptr(buf.buf_ptr);
 699         if (get_user(num_params, &uarg->num_params))
 700                 return -EFAULT;
 701
 702         if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) != buf.buf_len)
 703                 return -EINVAL;
 704
 705         params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
 706         if (!params)
 707                 return -ENOMEM;
 708
 709         rc = params_from_user(ctx, params, num_params, uarg->params);
 710         if (rc)
 711                 goto out;
 712
 713         rc = ctx->teedev->desc->ops->supp_recv(ctx, &func, &num_params, params);
 714         if (rc)
 715                 goto out;
 716
 717         if (put_user(func, &uarg->func) ||
 718             put_user(num_params, &uarg->num_params)) {
 719                 rc = -EFAULT;
 720                 goto out;
 721         }
 722
 723         rc = params_to_supp(ctx, uarg->params, num_params, params);
 724 out:
 725         kfree(params);
 726         return rc;
 727 }
 728
 729 static int params_from_supp(struct tee_param *params, size_t num_params,
 730                             struct tee_ioctl_param __user *uparams)
 731 {
 732         size_t n;
 733
 734         for (n = 0; n < num_params; n++) {
 735                 struct tee_param *p = params + n;
 736                 struct tee_ioctl_param ip;
 737
 738                 if (copy_from_user(&ip, uparams + n, sizeof(ip)))
 739                         return -EFAULT;
 740
 741                 /* All unused attribute bits has to be zero */
 742                 if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
 743                         return -EINVAL;
 744
 745                 p->attr = ip.attr;
 746                 switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
 747                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
 748                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 749                         /* Only out and in/out values can be updated */
 750                         p->u.value.a = ip.a;
 751                         p->u.value.b = ip.b;
 752                         p->u.value.c = ip.c;
 753                         break;
 754                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 755                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 756                         /*
 757                          * Only the size of the memref can be updated.
 758                          * Since we don't have access to the original
 759                          * parameters here, only store the supplied size.
 760                          * The driver will copy the updated size into the
 761                          * original parameters.
 762                          */
 763                         p->u.memref.shm = NULL;
 764                         p->u.memref.shm_offs = 0;
 765                         p->u.memref.size = ip.b;
 766                         break;
 767                 default:
 768                         memset(&p->u, 0, sizeof(p->u));
 769                         break;
 770                 }
 771         }
 772         return 0;
 773 }
 774
 775 static int tee_ioctl_supp_send(struct tee_context *ctx,
 776                                struct tee_ioctl_buf_data __user *ubuf)
 777 {
 778         long rc;
 779         struct tee_ioctl_buf_data buf;
 780         struct tee_iocl_supp_send_arg __user *uarg;
 781         struct tee_param *params;
 782         u32 num_params;
 783         u32 ret;
 784
 785         /* Not valid for this driver */
 786         if (!ctx->teedev->desc->ops->supp_send)
 787                 return -EINVAL;
 788
 789         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 790                 return -EFAULT;
 791
 792         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 793             buf.buf_len < sizeof(struct tee_iocl_supp_send_arg))
 794                 return -EINVAL;
 795
 796         uarg = u64_to_user_ptr(buf.buf_ptr);
 797         if (get_user(ret, &uarg->ret) ||
 798             get_user(num_params, &uarg->num_params))
 799                 return -EFAULT;
 800
 801         if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) > buf.buf_len)
 802                 return -EINVAL;
 803
 804         params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
 805         if (!params)
 806                 return -ENOMEM;
 807
 808         rc = params_from_supp(params, num_params, uarg->params);
 809         if (rc)
 810                 goto out;
 811
 812         rc = ctx->teedev->desc->ops->supp_send(ctx, ret, num_params, params);
 813 out:
 814         kfree(params);
 815         return rc;
 816 }
 817
 818 static long tee_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 819 {
 820         struct tee_context *ctx = filp->private_data;
 821         void __user *uarg = (void __user *)arg;
 822
 823         switch (cmd) {
 824         case TEE_IOC_VERSION:
 825                 return tee_ioctl_version(ctx, uarg);
 826         case TEE_IOC_SHM_ALLOC:
 827                 return tee_ioctl_shm_alloc(ctx, uarg);
 828         case TEE_IOC_SHM_REGISTER:
 829                 return tee_ioctl_shm_register(ctx, uarg);
 830         case TEE_IOC_OPEN_SESSION:
 831                 return tee_ioctl_open_session(ctx, uarg);
 832         case TEE_IOC_INVOKE:
 833                 return tee_ioctl_invoke(ctx, uarg);
 834         case TEE_IOC_CANCEL:
 835                 return tee_ioctl_cancel(ctx, uarg);
 836         case TEE_IOC_CLOSE_SESSION:
 837                 return tee_ioctl_close_session(ctx, uarg);
 838         case TEE_IOC_SUPPL_RECV:
 839                 return tee_ioctl_supp_recv(ctx, uarg);
 840         case TEE_IOC_SUPPL_SEND:
 841                 return tee_ioctl_supp_send(ctx, uarg);
 842         default:
 843                 return -EINVAL;
 844         }
 845 }
 846
 847 static const struct file_operations tee_fops = {
 848         .owner = THIS_MODULE,
 849         .open = tee_open,
 850         .release = tee_release,
 851         .unlocked_ioctl = tee_ioctl,
 852         .compat_ioctl = compat_ptr_ioctl,
 853 };
 854
 855 static void tee_release_device(struct device *dev)
 856 {
 857         struct tee_device *teedev = container_of(dev, struct tee_device, dev);
 858
 859         spin_lock(&driver_lock);
 860         clear_bit(teedev->id, dev_mask);
 861         spin_unlock(&driver_lock);
 862         mutex_destroy(&teedev->mutex);
 863         idr_destroy(&teedev->idr);
 864         kfree(teedev);
 865 }
 866
 867 /**
 868  * tee_device_alloc() - Allocate a new struct tee_device instance
 869  * @teedesc:    Descriptor for this driver
 870  * @dev:        Parent device for this device
 871  * @pool:       Shared memory pool, NULL if not used
 872  * @driver_data: Private driver data for this device
 873  *
 874  * Allocates a new struct tee_device instance. The device is
 875  * removed by tee_device_unregister().
 876  *
 877  * @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
 878  */
 879 struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
 880                                     struct device *dev,
 881                                     struct tee_shm_pool *pool,
 882                                     void *driver_data)
 883 {
 884         struct tee_device *teedev;
 885         void *ret;
 886         int rc, max_id;
 887         int offs = 0;
 888
 889         if (!teedesc || !teedesc->name || !teedesc->ops ||
 890             !teedesc->ops->get_version || !teedesc->ops->open ||
 891             !teedesc->ops->release || !pool)
 892                 return ERR_PTR(-EINVAL);
 893
 894         teedev = kzalloc(sizeof(*teedev), GFP_KERNEL);
 895         if (!teedev) {
 896                 ret = ERR_PTR(-ENOMEM);
 897                 goto err;
 898         }
 899
 900         max_id = TEE_NUM_DEVICES / 2;
 901
 902         if (teedesc->flags & TEE_DESC_PRIVILEGED) {
 903                 offs = TEE_NUM_DEVICES / 2;
 904                 max_id = TEE_NUM_DEVICES;
 905         }
 906
 907         spin_lock(&driver_lock);
 908         teedev->id = find_next_zero_bit(dev_mask, max_id, offs);
 909         if (teedev->id < max_id)
 910                 set_bit(teedev->id, dev_mask);
 911         spin_unlock(&driver_lock);
 912
 913         if (teedev->id >= max_id) {
 914                 ret = ERR_PTR(-ENOMEM);
 915                 goto err;
 916         }
 917
 918         snprintf(teedev->name, sizeof(teedev->name), "tee%s%d",
 919                  teedesc->flags & TEE_DESC_PRIVILEGED ? "priv" : "",
 920                  teedev->id - offs);
 921
 922         teedev->dev.class = tee_class;
 923         teedev->dev.release = tee_release_device;
 924         teedev->dev.parent = dev;
 925
 926         teedev->dev.devt = MKDEV(MAJOR(tee_devt), teedev->id);
 927
 928         rc = dev_set_name(&teedev->dev, "%s", teedev->name);
 929         if (rc) {
 930                 ret = ERR_PTR(rc);
 931                 goto err_devt;
 932         }
 933
 934         cdev_init(&teedev->cdev, &tee_fops);
 935         teedev->cdev.owner = teedesc->owner;
 936
 937         dev_set_drvdata(&teedev->dev, driver_data);
 938         device_initialize(&teedev->dev);
 939
 940         /* 1 as tee_device_unregister() does one final tee_device_put() */
 941         teedev->num_users = 1;
 942         init_completion(&teedev->c_no_users);
 943         mutex_init(&teedev->mutex);
 944         idr_init(&teedev->idr);
 945
 946         teedev->desc = teedesc;
 947         teedev->pool = pool;
 948
 949         return teedev;
 950 err_devt:
 951         unregister_chrdev_region(teedev->dev.devt, 1);
 952 err:
 953         pr_err("could not register %s driver\n",
 954                teedesc->flags & TEE_DESC_PRIVILEGED ? "privileged" : "client");
 955         if (teedev && teedev->id < TEE_NUM_DEVICES) {
 956                 spin_lock(&driver_lock);
 957                 clear_bit(teedev->id, dev_mask);
 958                 spin_unlock(&driver_lock);
 959         }
 960         kfree(teedev);
 961         return ret;
 962 }
 963 EXPORT_SYMBOL_GPL(tee_device_alloc);
 964
 965 static ssize_t implementation_id_show(struct device *dev,
 966                                       struct device_attribute *attr, char *buf)
 967 {
 968         struct tee_device *teedev = container_of(dev, struct tee_device, dev);
 969         struct tee_ioctl_version_data vers;
 970
 971         teedev->desc->ops->get_version(teedev, &vers);
 972         return scnprintf(buf, PAGE_SIZE, "%d\n", vers.impl_id);
 973 }
 974 static DEVICE_ATTR_RO(implementation_id);
 975
 976 static struct attribute *tee_dev_attrs[] = {
 977         &dev_attr_implementation_id.attr,
 978         NULL
 979 };
 980
 981 ATTRIBUTE_GROUPS(tee_dev);
 982
 983 /**
 984  * tee_device_register() - Registers a TEE device
 985  * @teedev:     Device to register
 986  *
 987  * tee_device_unregister() need to be called to remove the @teedev if
 988  * this function fails.
 989  *
 990  * @returns < 0 on failure
 991  */
 992 int tee_device_register(struct tee_device *teedev)
 993 {
 994         int rc;
 995
 996         if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
 997                 dev_err(&teedev->dev, "attempt to register twice\n");
 998                 return -EINVAL;
 999         }
1000
1001         teedev->dev.groups = tee_dev_groups;
1002
1003         rc = cdev_device_add(&teedev->cdev, &teedev->dev);
1004         if (rc) {
1005                 dev_err(&teedev->dev,
1006                         "unable to cdev_device_add() %s, major %d, minor %d, err=%d\n",
1007                         teedev->name, MAJOR(teedev->dev.devt),
1008                         MINOR(teedev->dev.devt), rc);
1009                 return rc;
1010         }
1011
1012         teedev->flags |= TEE_DEVICE_FLAG_REGISTERED;
1013         return 0;
1014 }
1015 EXPORT_SYMBOL_GPL(tee_device_register);
1016
1017 void tee_device_put(struct tee_device *teedev)
1018 {
1019         mutex_lock(&teedev->mutex);
1020         /* Shouldn't put in this state */
1021         if (!WARN_ON(!teedev->desc)) {
1022                 teedev->num_users--;
1023                 if (!teedev->num_users) {
1024                         teedev->desc = NULL;
1025                         complete(&teedev->c_no_users);
1026                 }
1027         }
1028         mutex_unlock(&teedev->mutex);
1029 }
1030
1031 bool tee_device_get(struct tee_device *teedev)
1032 {
1033         mutex_lock(&teedev->mutex);
1034         if (!teedev->desc) {
1035                 mutex_unlock(&teedev->mutex);
1036                 return false;
1037         }
1038         teedev->num_users++;
1039         mutex_unlock(&teedev->mutex);
1040         return true;
1041 }
1042
1043 /**
1044  * tee_device_unregister() - Removes a TEE device
1045  * @teedev:     Device to unregister
1046  *
1047  * This function should be called to remove the @teedev even if
1048  * tee_device_register() hasn't been called yet. Does nothing if
1049  * @teedev is NULL.
1050  */
1051 void tee_device_unregister(struct tee_device *teedev)
1052 {
1053         if (!teedev)
1054                 return;
1055
1056         if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED)
1057                 cdev_device_del(&teedev->cdev, &teedev->dev);
1058
1059         tee_device_put(teedev);
1060         wait_for_completion(&teedev->c_no_users);
1061
1062         /*
1063          * No need to take a mutex any longer now since teedev->desc was
1064          * set to NULL before teedev->c_no_users was completed.
1065          */
1066
1067         teedev->pool = NULL;
1068
1069         put_device(&teedev->dev);
1070 }
1071 EXPORT_SYMBOL_GPL(tee_device_unregister);
1072
1073 /**
1074  * tee_get_drvdata() - Return driver_data pointer
1075  * @teedev:     Device containing the driver_data pointer
1076  * @returns the driver_data pointer supplied to tee_device_alloc().
1077  */
1078 void *tee_get_drvdata(struct tee_device *teedev)
1079 {
1080         return dev_get_drvdata(&teedev->dev);
1081 }
1082 EXPORT_SYMBOL_GPL(tee_get_drvdata);
1083
1084 struct match_dev_data {
1085         struct tee_ioctl_version_data *vers;
1086         const void *data;
1087         int (*match)(struct tee_ioctl_version_data *, const void *);
1088 };
1089
1090 static int match_dev(struct device *dev, const void *data)
1091 {
1092         const struct match_dev_data *match_data = data;
1093         struct tee_device *teedev = container_of(dev, struct tee_device, dev);
1094
1095         teedev->desc->ops->get_version(teedev, match_data->vers);
1096         return match_data->match(match_data->vers, match_data->data);
1097 }
1098
1099 struct tee_context *
1100 tee_client_open_context(struct tee_context *start,
1101                         int (*match)(struct tee_ioctl_version_data *,
1102                                      const void *),
1103                         const void *data, struct tee_ioctl_version_data *vers)
1104 {
1105         struct device *dev = NULL;
1106         struct device *put_dev = NULL;
1107         struct tee_context *ctx = NULL;
1108         struct tee_ioctl_version_data v;
1109         struct match_dev_data match_data = { vers ? vers : &v, data, match };
1110
1111         if (start)
1112                 dev = &start->teedev->dev;
1113
1114         do {
1115                 dev = class_find_device(tee_class, dev, &match_data, match_dev);
1116                 if (!dev) {
1117                         ctx = ERR_PTR(-ENOENT);
1118                         break;
1119                 }
1120
1121                 put_device(put_dev);
1122                 put_dev = dev;
1123
1124                 ctx = teedev_open(container_of(dev, struct tee_device, dev));
1125         } while (IS_ERR(ctx) && PTR_ERR(ctx) != -ENOMEM);
1126
1127         put_device(put_dev);
1128         /*
1129          * Default behaviour for in kernel client is to not wait for
1130          * tee-supplicant if not present for any requests in this context.
1131          * Also this flag could be configured again before call to
1132          * tee_client_open_session() if any in kernel client requires
1133          * different behaviour.
1134          */
1135         if (!IS_ERR(ctx))
1136                 ctx->supp_nowait = true;
1137
1138         return ctx;
1139 }
1140 EXPORT_SYMBOL_GPL(tee_client_open_context);
1141
1142 void tee_client_close_context(struct tee_context *ctx)
1143 {
1144         teedev_close_context(ctx);
1145 }
1146 EXPORT_SYMBOL_GPL(tee_client_close_context);
1147
1148 void tee_client_get_version(struct tee_context *ctx,
1149                             struct tee_ioctl_version_data *vers)
1150 {
1151         ctx->teedev->desc->ops->get_version(ctx->teedev, vers);
1152 }
1153 EXPORT_SYMBOL_GPL(tee_client_get_version);
1154
1155 int tee_client_open_session(struct tee_context *ctx,
1156                             struct tee_ioctl_open_session_arg *arg,
1157                             struct tee_param *param)
1158 {
1159         if (!ctx->teedev->desc->ops->open_session)
1160                 return -EINVAL;
1161         return ctx->teedev->desc->ops->open_session(ctx, arg, param);
1162 }
1163 EXPORT_SYMBOL_GPL(tee_client_open_session);
1164
1165 int tee_client_close_session(struct tee_context *ctx, u32 session)
1166 {
1167         if (!ctx->teedev->desc->ops->close_session)
1168                 return -EINVAL;
1169         return ctx->teedev->desc->ops->close_session(ctx, session);
1170 }
1171 EXPORT_SYMBOL_GPL(tee_client_close_session);
1172
1173 int tee_client_invoke_func(struct tee_context *ctx,
1174                            struct tee_ioctl_invoke_arg *arg,
1175                            struct tee_param *param)
1176 {
1177         if (!ctx->teedev->desc->ops->invoke_func)
1178                 return -EINVAL;
1179         return ctx->teedev->desc->ops->invoke_func(ctx, arg, param);
1180 }
1181 EXPORT_SYMBOL_GPL(tee_client_invoke_func);
1182
1183 int tee_client_cancel_req(struct tee_context *ctx,
1184                           struct tee_ioctl_cancel_arg *arg)
1185 {
1186         if (!ctx->teedev->desc->ops->cancel_req)
1187                 return -EINVAL;
1188         return ctx->teedev->desc->ops->cancel_req(ctx, arg->cancel_id,
1189                                                   arg->session);
1190 }
1191
1192 static int tee_client_device_match(struct device *dev,
1193                                    struct device_driver *drv)
1194 {
1195         const struct tee_client_device_id *id_table;
1196         struct tee_client_device *tee_device;
1197
1198         id_table = to_tee_client_driver(drv)->id_table;
1199         tee_device = to_tee_client_device(dev);
1200
1201         while (!uuid_is_null(&id_table->uuid)) {
1202                 if (uuid_equal(&tee_device->id.uuid, &id_table->uuid))
1203                         return 1;
1204                 id_table++;
1205         }
1206
1207         return 0;
1208 }
1209
1210 static int tee_client_device_uevent(struct device *dev,
1211                                     struct kobj_uevent_env *env)
1212 {
1213         uuid_t *dev_id = &to_tee_client_device(dev)->id.uuid;
1214
1215         return add_uevent_var(env, "MODALIAS=tee:%pUb", dev_id);
1216 }
1217
1218 struct bus_type tee_bus_type = {
1219         .name           = "tee",
1220         .match          = tee_client_device_match,
1221         .uevent         = tee_client_device_uevent,
1222 };
1223 EXPORT_SYMBOL_GPL(tee_bus_type);
1224
1225 static int __init tee_init(void)
1226 {
1227         int rc;
1228
1229         tee_class = class_create(THIS_MODULE, "tee");
1230         if (IS_ERR(tee_class)) {
1231                 pr_err("couldn't create class\n");
1232                 return PTR_ERR(tee_class);
1233         }
1234
1235         rc = alloc_chrdev_region(&tee_devt, 0, TEE_NUM_DEVICES, "tee");
1236         if (rc) {
1237                 pr_err("failed to allocate char dev region\n");
1238                 goto out_unreg_class;
1239         }
1240
1241         rc = bus_register(&tee_bus_type);
1242         if (rc) {
1243                 pr_err("failed to register tee bus\n");
1244                 goto out_unreg_chrdev;
1245         }
1246
1247         return 0;
1248
1249 out_unreg_chrdev:
1250         unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1251 out_unreg_class:
1252         class_destroy(tee_class);
1253         tee_class = NULL;
1254
1255         return rc;
1256 }
1257
1258 static void __exit tee_exit(void)
1259 {
1260         bus_unregister(&tee_bus_type);
1261         unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1262         class_destroy(tee_class);
1263         tee_class = NULL;
1264 }
1265
1266 subsys_initcall(tee_init);
1267 module_exit(tee_exit);
1268
1269 MODULE_AUTHOR("Linaro");
1270 MODULE_DESCRIPTION("TEE Driver");
1271 MODULE_VERSION("1.0");
1272 MODULE_LICENSE("GPL v2");