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