linux/drivers/tee/tee_core.c
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   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 */
  32static 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 */
  40static DECLARE_BITMAP(dev_mask, TEE_NUM_DEVICES);
  41static DEFINE_SPINLOCK(driver_lock);
  42
  43static struct class *tee_class;
  44static dev_t tee_devt;
  45
  46static 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;
  67err:
  68        kfree(ctx);
  69        tee_device_put(teedev);
  70        return ERR_PTR(rc);
  71
  72}
  73
  74void teedev_ctx_get(struct tee_context *ctx)
  75{
  76        if (ctx->releasing)
  77                return;
  78
  79        kref_get(&ctx->refcount);
  80}
  81
  82static 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
  91void 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
  99static void teedev_close_context(struct tee_context *ctx)
 100{
 101        tee_device_put(ctx->teedev);
 102        teedev_ctx_put(ctx);
 103}
 104
 105static 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
 122static 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 */
 140static 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
 186out_free_desc:
 187        kfree(desc);
 188
 189out_free_shash:
 190        crypto_free_shash(shash);
 191        return rc;
 192}
 193
 194int tee_session_calc_client_uuid(uuid_t *uuid, u32 connection_method,
 195                                 const u8 connection_data[TEE_IOCTL_UUID_LEN])
 196{
 197        gid_t ns_grp = (gid_t)-1;
 198        kgid_t grp = INVALID_GID;
 199        char *name = NULL;
 200        int name_len;
 201        int rc;
 202
 203        if (connection_method == TEE_IOCTL_LOGIN_PUBLIC ||
 204            connection_method == TEE_IOCTL_LOGIN_REE_KERNEL) {
 205                /* Nil UUID to be passed to TEE environment */
 206                uuid_copy(uuid, &uuid_null);
 207                return 0;
 208        }
 209
 210        /*
 211         * In Linux environment client UUID is based on UUIDv5.
 212         *
 213         * Determine client UUID with following semantics for 'name':
 214         *
 215         * For TEEC_LOGIN_USER:
 216         * uid=<uid>
 217         *
 218         * For TEEC_LOGIN_GROUP:
 219         * gid=<gid>
 220         *
 221         */
 222
 223        name = kzalloc(TEE_UUID_NS_NAME_SIZE, GFP_KERNEL);
 224        if (!name)
 225                return -ENOMEM;
 226
 227        switch (connection_method) {
 228        case TEE_IOCTL_LOGIN_USER:
 229                name_len = snprintf(name, TEE_UUID_NS_NAME_SIZE, "uid=%x",
 230                                    current_euid().val);
 231                if (name_len >= TEE_UUID_NS_NAME_SIZE) {
 232                        rc = -E2BIG;
 233                        goto out_free_name;
 234                }
 235                break;
 236
 237        case TEE_IOCTL_LOGIN_GROUP:
 238                memcpy(&ns_grp, connection_data, sizeof(gid_t));
 239                grp = make_kgid(current_user_ns(), ns_grp);
 240                if (!gid_valid(grp) || !in_egroup_p(grp)) {
 241                        rc = -EPERM;
 242                        goto out_free_name;
 243                }
 244
 245                name_len = snprintf(name, TEE_UUID_NS_NAME_SIZE, "gid=%x",
 246                                    grp.val);
 247                if (name_len >= TEE_UUID_NS_NAME_SIZE) {
 248                        rc = -E2BIG;
 249                        goto out_free_name;
 250                }
 251                break;
 252
 253        default:
 254                rc = -EINVAL;
 255                goto out_free_name;
 256        }
 257
 258        rc = uuid_v5(uuid, &tee_client_uuid_ns, name, name_len);
 259out_free_name:
 260        kfree(name);
 261
 262        return rc;
 263}
 264EXPORT_SYMBOL_GPL(tee_session_calc_client_uuid);
 265
 266static int tee_ioctl_version(struct tee_context *ctx,
 267                             struct tee_ioctl_version_data __user *uvers)
 268{
 269        struct tee_ioctl_version_data vers;
 270
 271        ctx->teedev->desc->ops->get_version(ctx->teedev, &vers);
 272
 273        if (ctx->teedev->desc->flags & TEE_DESC_PRIVILEGED)
 274                vers.gen_caps |= TEE_GEN_CAP_PRIVILEGED;
 275
 276        if (copy_to_user(uvers, &vers, sizeof(vers)))
 277                return -EFAULT;
 278
 279        return 0;
 280}
 281
 282static int tee_ioctl_shm_alloc(struct tee_context *ctx,
 283                               struct tee_ioctl_shm_alloc_data __user *udata)
 284{
 285        long ret;
 286        struct tee_ioctl_shm_alloc_data data;
 287        struct tee_shm *shm;
 288
 289        if (copy_from_user(&data, udata, sizeof(data)))
 290                return -EFAULT;
 291
 292        /* Currently no input flags are supported */
 293        if (data.flags)
 294                return -EINVAL;
 295
 296        shm = tee_shm_alloc(ctx, data.size, TEE_SHM_MAPPED | TEE_SHM_DMA_BUF);
 297        if (IS_ERR(shm))
 298                return PTR_ERR(shm);
 299
 300        data.id = shm->id;
 301        data.flags = shm->flags;
 302        data.size = shm->size;
 303
 304        if (copy_to_user(udata, &data, sizeof(data)))
 305                ret = -EFAULT;
 306        else
 307                ret = tee_shm_get_fd(shm);
 308
 309        /*
 310         * When user space closes the file descriptor the shared memory
 311         * should be freed or if tee_shm_get_fd() failed then it will
 312         * be freed immediately.
 313         */
 314        tee_shm_put(shm);
 315        return ret;
 316}
 317
 318static int
 319tee_ioctl_shm_register(struct tee_context *ctx,
 320                       struct tee_ioctl_shm_register_data __user *udata)
 321{
 322        long ret;
 323        struct tee_ioctl_shm_register_data data;
 324        struct tee_shm *shm;
 325
 326        if (copy_from_user(&data, udata, sizeof(data)))
 327                return -EFAULT;
 328
 329        /* Currently no input flags are supported */
 330        if (data.flags)
 331                return -EINVAL;
 332
 333        shm = tee_shm_register(ctx, data.addr, data.length,
 334                               TEE_SHM_DMA_BUF | TEE_SHM_USER_MAPPED);
 335        if (IS_ERR(shm))
 336                return PTR_ERR(shm);
 337
 338        data.id = shm->id;
 339        data.flags = shm->flags;
 340        data.length = shm->size;
 341
 342        if (copy_to_user(udata, &data, sizeof(data)))
 343                ret = -EFAULT;
 344        else
 345                ret = tee_shm_get_fd(shm);
 346        /*
 347         * When user space closes the file descriptor the shared memory
 348         * should be freed or if tee_shm_get_fd() failed then it will
 349         * be freed immediately.
 350         */
 351        tee_shm_put(shm);
 352        return ret;
 353}
 354
 355static int params_from_user(struct tee_context *ctx, struct tee_param *params,
 356                            size_t num_params,
 357                            struct tee_ioctl_param __user *uparams)
 358{
 359        size_t n;
 360
 361        for (n = 0; n < num_params; n++) {
 362                struct tee_shm *shm;
 363                struct tee_ioctl_param ip;
 364
 365                if (copy_from_user(&ip, uparams + n, sizeof(ip)))
 366                        return -EFAULT;
 367
 368                /* All unused attribute bits has to be zero */
 369                if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
 370                        return -EINVAL;
 371
 372                params[n].attr = ip.attr;
 373                switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
 374                case TEE_IOCTL_PARAM_ATTR_TYPE_NONE:
 375                case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
 376                        break;
 377                case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
 378                case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 379                        params[n].u.value.a = ip.a;
 380                        params[n].u.value.b = ip.b;
 381                        params[n].u.value.c = ip.c;
 382                        break;
 383                case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
 384                case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 385                case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 386                        /*
 387                         * If a NULL pointer is passed to a TA in the TEE,
 388                         * the ip.c IOCTL parameters is set to TEE_MEMREF_NULL
 389                         * indicating a NULL memory reference.
 390                         */
 391                        if (ip.c != TEE_MEMREF_NULL) {
 392                                /*
 393                                 * If we fail to get a pointer to a shared
 394                                 * memory object (and increase the ref count)
 395                                 * from an identifier we return an error. All
 396                                 * pointers that has been added in params have
 397                                 * an increased ref count. It's the callers
 398                                 * responibility to do tee_shm_put() on all
 399                                 * resolved pointers.
 400                                 */
 401                                shm = tee_shm_get_from_id(ctx, ip.c);
 402                                if (IS_ERR(shm))
 403                                        return PTR_ERR(shm);
 404
 405                                /*
 406                                 * Ensure offset + size does not overflow
 407                                 * offset and does not overflow the size of
 408                                 * the referred shared memory object.
 409                                 */
 410                                if ((ip.a + ip.b) < ip.a ||
 411                                    (ip.a + ip.b) > shm->size) {
 412                                        tee_shm_put(shm);
 413                                        return -EINVAL;
 414                                }
 415                        } else if (ctx->cap_memref_null) {
 416                                /* Pass NULL pointer to OP-TEE */
 417                                shm = NULL;
 418                        } else {
 419                                return -EINVAL;
 420                        }
 421
 422                        params[n].u.memref.shm_offs = ip.a;
 423                        params[n].u.memref.size = ip.b;
 424                        params[n].u.memref.shm = shm;
 425                        break;
 426                default:
 427                        /* Unknown attribute */
 428                        return -EINVAL;
 429                }
 430        }
 431        return 0;
 432}
 433
 434static int params_to_user(struct tee_ioctl_param __user *uparams,
 435                          size_t num_params, struct tee_param *params)
 436{
 437        size_t n;
 438
 439        for (n = 0; n < num_params; n++) {
 440                struct tee_ioctl_param __user *up = uparams + n;
 441                struct tee_param *p = params + n;
 442
 443                switch (p->attr) {
 444                case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
 445                case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 446                        if (put_user(p->u.value.a, &up->a) ||
 447                            put_user(p->u.value.b, &up->b) ||
 448                            put_user(p->u.value.c, &up->c))
 449                                return -EFAULT;
 450                        break;
 451                case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 452                case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 453                        if (put_user((u64)p->u.memref.size, &up->b))
 454                                return -EFAULT;
 455                default:
 456                        break;
 457                }
 458        }
 459        return 0;
 460}
 461
 462static int tee_ioctl_open_session(struct tee_context *ctx,
 463                                  struct tee_ioctl_buf_data __user *ubuf)
 464{
 465        int rc;
 466        size_t n;
 467        struct tee_ioctl_buf_data buf;
 468        struct tee_ioctl_open_session_arg __user *uarg;
 469        struct tee_ioctl_open_session_arg arg;
 470        struct tee_ioctl_param __user *uparams = NULL;
 471        struct tee_param *params = NULL;
 472        bool have_session = false;
 473
 474        if (!ctx->teedev->desc->ops->open_session)
 475                return -EINVAL;
 476
 477        if (copy_from_user(&buf, ubuf, sizeof(buf)))
 478                return -EFAULT;
 479
 480        if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 481            buf.buf_len < sizeof(struct tee_ioctl_open_session_arg))
 482                return -EINVAL;
 483
 484        uarg = u64_to_user_ptr(buf.buf_ptr);
 485        if (copy_from_user(&arg, uarg, sizeof(arg)))
 486                return -EFAULT;
 487
 488        if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
 489                return -EINVAL;
 490
 491        if (arg.num_params) {
 492                params = kcalloc(arg.num_params, sizeof(struct tee_param),
 493                                 GFP_KERNEL);
 494                if (!params)
 495                        return -ENOMEM;
 496                uparams = uarg->params;
 497                rc = params_from_user(ctx, params, arg.num_params, uparams);
 498                if (rc)
 499                        goto out;
 500        }
 501
 502        if (arg.clnt_login >= TEE_IOCTL_LOGIN_REE_KERNEL_MIN &&
 503            arg.clnt_login <= TEE_IOCTL_LOGIN_REE_KERNEL_MAX) {
 504                pr_debug("login method not allowed for user-space client\n");
 505                rc = -EPERM;
 506                goto out;
 507        }
 508
 509        rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params);
 510        if (rc)
 511                goto out;
 512        have_session = true;
 513
 514        if (put_user(arg.session, &uarg->session) ||
 515            put_user(arg.ret, &uarg->ret) ||
 516            put_user(arg.ret_origin, &uarg->ret_origin)) {
 517                rc = -EFAULT;
 518                goto out;
 519        }
 520        rc = params_to_user(uparams, arg.num_params, params);
 521out:
 522        /*
 523         * If we've succeeded to open the session but failed to communicate
 524         * it back to user space, close the session again to avoid leakage.
 525         */
 526        if (rc && have_session && ctx->teedev->desc->ops->close_session)
 527                ctx->teedev->desc->ops->close_session(ctx, arg.session);
 528
 529        if (params) {
 530                /* Decrease ref count for all valid shared memory pointers */
 531                for (n = 0; n < arg.num_params; n++)
 532                        if (tee_param_is_memref(params + n) &&
 533                            params[n].u.memref.shm)
 534                                tee_shm_put(params[n].u.memref.shm);
 535                kfree(params);
 536        }
 537
 538        return rc;
 539}
 540
 541static int tee_ioctl_invoke(struct tee_context *ctx,
 542                            struct tee_ioctl_buf_data __user *ubuf)
 543{
 544        int rc;
 545        size_t n;
 546        struct tee_ioctl_buf_data buf;
 547        struct tee_ioctl_invoke_arg __user *uarg;
 548        struct tee_ioctl_invoke_arg arg;
 549        struct tee_ioctl_param __user *uparams = NULL;
 550        struct tee_param *params = NULL;
 551
 552        if (!ctx->teedev->desc->ops->invoke_func)
 553                return -EINVAL;
 554
 555        if (copy_from_user(&buf, ubuf, sizeof(buf)))
 556                return -EFAULT;
 557
 558        if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 559            buf.buf_len < sizeof(struct tee_ioctl_invoke_arg))
 560                return -EINVAL;
 561
 562        uarg = u64_to_user_ptr(buf.buf_ptr);
 563        if (copy_from_user(&arg, uarg, sizeof(arg)))
 564                return -EFAULT;
 565
 566        if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
 567                return -EINVAL;
 568
 569        if (arg.num_params) {
 570                params = kcalloc(arg.num_params, sizeof(struct tee_param),
 571                                 GFP_KERNEL);
 572                if (!params)
 573                        return -ENOMEM;
 574                uparams = uarg->params;
 575                rc = params_from_user(ctx, params, arg.num_params, uparams);
 576                if (rc)
 577                        goto out;
 578        }
 579
 580        rc = ctx->teedev->desc->ops->invoke_func(ctx, &arg, params);
 581        if (rc)
 582                goto out;
 583
 584        if (put_user(arg.ret, &uarg->ret) ||
 585            put_user(arg.ret_origin, &uarg->ret_origin)) {
 586                rc = -EFAULT;
 587                goto out;
 588        }
 589        rc = params_to_user(uparams, arg.num_params, params);
 590out:
 591        if (params) {
 592                /* Decrease ref count for all valid shared memory pointers */
 593                for (n = 0; n < arg.num_params; n++)
 594                        if (tee_param_is_memref(params + n) &&
 595                            params[n].u.memref.shm)
 596                                tee_shm_put(params[n].u.memref.shm);
 597                kfree(params);
 598        }
 599        return rc;
 600}
 601
 602static int tee_ioctl_cancel(struct tee_context *ctx,
 603                            struct tee_ioctl_cancel_arg __user *uarg)
 604{
 605        struct tee_ioctl_cancel_arg arg;
 606
 607        if (!ctx->teedev->desc->ops->cancel_req)
 608                return -EINVAL;
 609
 610        if (copy_from_user(&arg, uarg, sizeof(arg)))
 611                return -EFAULT;
 612
 613        return ctx->teedev->desc->ops->cancel_req(ctx, arg.cancel_id,
 614                                                  arg.session);
 615}
 616
 617static int
 618tee_ioctl_close_session(struct tee_context *ctx,
 619                        struct tee_ioctl_close_session_arg __user *uarg)
 620{
 621        struct tee_ioctl_close_session_arg arg;
 622
 623        if (!ctx->teedev->desc->ops->close_session)
 624                return -EINVAL;
 625
 626        if (copy_from_user(&arg, uarg, sizeof(arg)))
 627                return -EFAULT;
 628
 629        return ctx->teedev->desc->ops->close_session(ctx, arg.session);
 630}
 631
 632static int params_to_supp(struct tee_context *ctx,
 633                          struct tee_ioctl_param __user *uparams,
 634                          size_t num_params, struct tee_param *params)
 635{
 636        size_t n;
 637
 638        for (n = 0; n < num_params; n++) {
 639                struct tee_ioctl_param ip;
 640                struct tee_param *p = params + n;
 641
 642                ip.attr = p->attr;
 643                switch (p->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
 644                case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
 645                case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 646                        ip.a = p->u.value.a;
 647                        ip.b = p->u.value.b;
 648                        ip.c = p->u.value.c;
 649                        break;
 650                case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
 651                case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 652                case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 653                        ip.b = p->u.memref.size;
 654                        if (!p->u.memref.shm) {
 655                                ip.a = 0;
 656                                ip.c = (u64)-1; /* invalid shm id */
 657                                break;
 658                        }
 659                        ip.a = p->u.memref.shm_offs;
 660                        ip.c = p->u.memref.shm->id;
 661                        break;
 662                default:
 663                        ip.a = 0;
 664                        ip.b = 0;
 665                        ip.c = 0;
 666                        break;
 667                }
 668
 669                if (copy_to_user(uparams + n, &ip, sizeof(ip)))
 670                        return -EFAULT;
 671        }
 672
 673        return 0;
 674}
 675
 676static int tee_ioctl_supp_recv(struct tee_context *ctx,
 677                               struct tee_ioctl_buf_data __user *ubuf)
 678{
 679        int rc;
 680        struct tee_ioctl_buf_data buf;
 681        struct tee_iocl_supp_recv_arg __user *uarg;
 682        struct tee_param *params;
 683        u32 num_params;
 684        u32 func;
 685
 686        if (!ctx->teedev->desc->ops->supp_recv)
 687                return -EINVAL;
 688
 689        if (copy_from_user(&buf, ubuf, sizeof(buf)))
 690                return -EFAULT;
 691
 692        if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 693            buf.buf_len < sizeof(struct tee_iocl_supp_recv_arg))
 694                return -EINVAL;
 695
 696        uarg = u64_to_user_ptr(buf.buf_ptr);
 697        if (get_user(num_params, &uarg->num_params))
 698                return -EFAULT;
 699
 700        if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) != buf.buf_len)
 701                return -EINVAL;
 702
 703        params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
 704        if (!params)
 705                return -ENOMEM;
 706
 707        rc = params_from_user(ctx, params, num_params, uarg->params);
 708        if (rc)
 709                goto out;
 710
 711        rc = ctx->teedev->desc->ops->supp_recv(ctx, &func, &num_params, params);
 712        if (rc)
 713                goto out;
 714
 715        if (put_user(func, &uarg->func) ||
 716            put_user(num_params, &uarg->num_params)) {
 717                rc = -EFAULT;
 718                goto out;
 719        }
 720
 721        rc = params_to_supp(ctx, uarg->params, num_params, params);
 722out:
 723        kfree(params);
 724        return rc;
 725}
 726
 727static int params_from_supp(struct tee_param *params, size_t num_params,
 728                            struct tee_ioctl_param __user *uparams)
 729{
 730        size_t n;
 731
 732        for (n = 0; n < num_params; n++) {
 733                struct tee_param *p = params + n;
 734                struct tee_ioctl_param ip;
 735
 736                if (copy_from_user(&ip, uparams + n, sizeof(ip)))
 737                        return -EFAULT;
 738
 739                /* All unused attribute bits has to be zero */
 740                if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
 741                        return -EINVAL;
 742
 743                p->attr = ip.attr;
 744                switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
 745                case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
 746                case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 747                        /* Only out and in/out values can be updated */
 748                        p->u.value.a = ip.a;
 749                        p->u.value.b = ip.b;
 750                        p->u.value.c = ip.c;
 751                        break;
 752                case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 753                case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 754                        /*
 755                         * Only the size of the memref can be updated.
 756                         * Since we don't have access to the original
 757                         * parameters here, only store the supplied size.
 758                         * The driver will copy the updated size into the
 759                         * original parameters.
 760                         */
 761                        p->u.memref.shm = NULL;
 762                        p->u.memref.shm_offs = 0;
 763                        p->u.memref.size = ip.b;
 764                        break;
 765                default:
 766                        memset(&p->u, 0, sizeof(p->u));
 767                        break;
 768                }
 769        }
 770        return 0;
 771}
 772
 773static int tee_ioctl_supp_send(struct tee_context *ctx,
 774                               struct tee_ioctl_buf_data __user *ubuf)
 775{
 776        long rc;
 777        struct tee_ioctl_buf_data buf;
 778        struct tee_iocl_supp_send_arg __user *uarg;
 779        struct tee_param *params;
 780        u32 num_params;
 781        u32 ret;
 782
 783        /* Not valid for this driver */
 784        if (!ctx->teedev->desc->ops->supp_send)
 785                return -EINVAL;
 786
 787        if (copy_from_user(&buf, ubuf, sizeof(buf)))
 788                return -EFAULT;
 789
 790        if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 791            buf.buf_len < sizeof(struct tee_iocl_supp_send_arg))
 792                return -EINVAL;
 793
 794        uarg = u64_to_user_ptr(buf.buf_ptr);
 795        if (get_user(ret, &uarg->ret) ||
 796            get_user(num_params, &uarg->num_params))
 797                return -EFAULT;
 798
 799        if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) > buf.buf_len)
 800                return -EINVAL;
 801
 802        params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
 803        if (!params)
 804                return -ENOMEM;
 805
 806        rc = params_from_supp(params, num_params, uarg->params);
 807        if (rc)
 808                goto out;
 809
 810        rc = ctx->teedev->desc->ops->supp_send(ctx, ret, num_params, params);
 811out:
 812        kfree(params);
 813        return rc;
 814}
 815
 816static long tee_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 817{
 818        struct tee_context *ctx = filp->private_data;
 819        void __user *uarg = (void __user *)arg;
 820
 821        switch (cmd) {
 822        case TEE_IOC_VERSION:
 823                return tee_ioctl_version(ctx, uarg);
 824        case TEE_IOC_SHM_ALLOC:
 825                return tee_ioctl_shm_alloc(ctx, uarg);
 826        case TEE_IOC_SHM_REGISTER:
 827                return tee_ioctl_shm_register(ctx, uarg);
 828        case TEE_IOC_OPEN_SESSION:
 829                return tee_ioctl_open_session(ctx, uarg);
 830        case TEE_IOC_INVOKE:
 831                return tee_ioctl_invoke(ctx, uarg);
 832        case TEE_IOC_CANCEL:
 833                return tee_ioctl_cancel(ctx, uarg);
 834        case TEE_IOC_CLOSE_SESSION:
 835                return tee_ioctl_close_session(ctx, uarg);
 836        case TEE_IOC_SUPPL_RECV:
 837                return tee_ioctl_supp_recv(ctx, uarg);
 838        case TEE_IOC_SUPPL_SEND:
 839                return tee_ioctl_supp_send(ctx, uarg);
 840        default:
 841                return -EINVAL;
 842        }
 843}
 844
 845static const struct file_operations tee_fops = {
 846        .owner = THIS_MODULE,
 847        .open = tee_open,
 848        .release = tee_release,
 849        .unlocked_ioctl = tee_ioctl,
 850        .compat_ioctl = compat_ptr_ioctl,
 851};
 852
 853static void tee_release_device(struct device *dev)
 854{
 855        struct tee_device *teedev = container_of(dev, struct tee_device, dev);
 856
 857        spin_lock(&driver_lock);
 858        clear_bit(teedev->id, dev_mask);
 859        spin_unlock(&driver_lock);
 860        mutex_destroy(&teedev->mutex);
 861        idr_destroy(&teedev->idr);
 862        kfree(teedev);
 863}
 864
 865/**
 866 * tee_device_alloc() - Allocate a new struct tee_device instance
 867 * @teedesc:    Descriptor for this driver
 868 * @dev:        Parent device for this device
 869 * @pool:       Shared memory pool, NULL if not used
 870 * @driver_data: Private driver data for this device
 871 *
 872 * Allocates a new struct tee_device instance. The device is
 873 * removed by tee_device_unregister().
 874 *
 875 * @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
 876 */
 877struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
 878                                    struct device *dev,
 879                                    struct tee_shm_pool *pool,
 880                                    void *driver_data)
 881{
 882        struct tee_device *teedev;
 883        void *ret;
 884        int rc, max_id;
 885        int offs = 0;
 886
 887        if (!teedesc || !teedesc->name || !teedesc->ops ||
 888            !teedesc->ops->get_version || !teedesc->ops->open ||
 889            !teedesc->ops->release || !pool)
 890                return ERR_PTR(-EINVAL);
 891
 892        teedev = kzalloc(sizeof(*teedev), GFP_KERNEL);
 893        if (!teedev) {
 894                ret = ERR_PTR(-ENOMEM);
 895                goto err;
 896        }
 897
 898        max_id = TEE_NUM_DEVICES / 2;
 899
 900        if (teedesc->flags & TEE_DESC_PRIVILEGED) {
 901                offs = TEE_NUM_DEVICES / 2;
 902                max_id = TEE_NUM_DEVICES;
 903        }
 904
 905        spin_lock(&driver_lock);
 906        teedev->id = find_next_zero_bit(dev_mask, max_id, offs);
 907        if (teedev->id < max_id)
 908                set_bit(teedev->id, dev_mask);
 909        spin_unlock(&driver_lock);
 910
 911        if (teedev->id >= max_id) {
 912                ret = ERR_PTR(-ENOMEM);
 913                goto err;
 914        }
 915
 916        snprintf(teedev->name, sizeof(teedev->name), "tee%s%d",
 917                 teedesc->flags & TEE_DESC_PRIVILEGED ? "priv" : "",
 918                 teedev->id - offs);
 919
 920        teedev->dev.class = tee_class;
 921        teedev->dev.release = tee_release_device;
 922        teedev->dev.parent = dev;
 923
 924        teedev->dev.devt = MKDEV(MAJOR(tee_devt), teedev->id);
 925
 926        rc = dev_set_name(&teedev->dev, "%s", teedev->name);
 927        if (rc) {
 928                ret = ERR_PTR(rc);
 929                goto err_devt;
 930        }
 931
 932        cdev_init(&teedev->cdev, &tee_fops);
 933        teedev->cdev.owner = teedesc->owner;
 934
 935        dev_set_drvdata(&teedev->dev, driver_data);
 936        device_initialize(&teedev->dev);
 937
 938        /* 1 as tee_device_unregister() does one final tee_device_put() */
 939        teedev->num_users = 1;
 940        init_completion(&teedev->c_no_users);
 941        mutex_init(&teedev->mutex);
 942        idr_init(&teedev->idr);
 943
 944        teedev->desc = teedesc;
 945        teedev->pool = pool;
 946
 947        return teedev;
 948err_devt:
 949        unregister_chrdev_region(teedev->dev.devt, 1);
 950err:
 951        pr_err("could not register %s driver\n",
 952               teedesc->flags & TEE_DESC_PRIVILEGED ? "privileged" : "client");
 953        if (teedev && teedev->id < TEE_NUM_DEVICES) {
 954                spin_lock(&driver_lock);
 955                clear_bit(teedev->id, dev_mask);
 956                spin_unlock(&driver_lock);
 957        }
 958        kfree(teedev);
 959        return ret;
 960}
 961EXPORT_SYMBOL_GPL(tee_device_alloc);
 962
 963static ssize_t implementation_id_show(struct device *dev,
 964                                      struct device_attribute *attr, char *buf)
 965{
 966        struct tee_device *teedev = container_of(dev, struct tee_device, dev);
 967        struct tee_ioctl_version_data vers;
 968
 969        teedev->desc->ops->get_version(teedev, &vers);
 970        return scnprintf(buf, PAGE_SIZE, "%d\n", vers.impl_id);
 971}
 972static DEVICE_ATTR_RO(implementation_id);
 973
 974static struct attribute *tee_dev_attrs[] = {
 975        &dev_attr_implementation_id.attr,
 976        NULL
 977};
 978
 979ATTRIBUTE_GROUPS(tee_dev);
 980
 981/**
 982 * tee_device_register() - Registers a TEE device
 983 * @teedev:     Device to register
 984 *
 985 * tee_device_unregister() need to be called to remove the @teedev if
 986 * this function fails.
 987 *
 988 * @returns < 0 on failure
 989 */
 990int tee_device_register(struct tee_device *teedev)
 991{
 992        int rc;
 993
 994        if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
 995                dev_err(&teedev->dev, "attempt to register twice\n");
 996                return -EINVAL;
 997        }
 998
 999        teedev->dev.groups = tee_dev_groups;
1000
1001        rc = cdev_device_add(&teedev->cdev, &teedev->dev);
1002        if (rc) {
1003                dev_err(&teedev->dev,
1004                        "unable to cdev_device_add() %s, major %d, minor %d, err=%d\n",
1005                        teedev->name, MAJOR(teedev->dev.devt),
1006                        MINOR(teedev->dev.devt), rc);
1007                return rc;
1008        }
1009
1010        teedev->flags |= TEE_DEVICE_FLAG_REGISTERED;
1011        return 0;
1012}
1013EXPORT_SYMBOL_GPL(tee_device_register);
1014
1015void tee_device_put(struct tee_device *teedev)
1016{
1017        mutex_lock(&teedev->mutex);
1018        /* Shouldn't put in this state */
1019        if (!WARN_ON(!teedev->desc)) {
1020                teedev->num_users--;
1021                if (!teedev->num_users) {
1022                        teedev->desc = NULL;
1023                        complete(&teedev->c_no_users);
1024                }
1025        }
1026        mutex_unlock(&teedev->mutex);
1027}
1028
1029bool tee_device_get(struct tee_device *teedev)
1030{
1031        mutex_lock(&teedev->mutex);
1032        if (!teedev->desc) {
1033                mutex_unlock(&teedev->mutex);
1034                return false;
1035        }
1036        teedev->num_users++;
1037        mutex_unlock(&teedev->mutex);
1038        return true;
1039}
1040
1041/**
1042 * tee_device_unregister() - Removes a TEE device
1043 * @teedev:     Device to unregister
1044 *
1045 * This function should be called to remove the @teedev even if
1046 * tee_device_register() hasn't been called yet. Does nothing if
1047 * @teedev is NULL.
1048 */
1049void tee_device_unregister(struct tee_device *teedev)
1050{
1051        if (!teedev)
1052                return;
1053
1054        if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED)
1055                cdev_device_del(&teedev->cdev, &teedev->dev);
1056
1057        tee_device_put(teedev);
1058        wait_for_completion(&teedev->c_no_users);
1059
1060        /*
1061         * No need to take a mutex any longer now since teedev->desc was
1062         * set to NULL before teedev->c_no_users was completed.
1063         */
1064
1065        teedev->pool = NULL;
1066
1067        put_device(&teedev->dev);
1068}
1069EXPORT_SYMBOL_GPL(tee_device_unregister);
1070
1071/**
1072 * tee_get_drvdata() - Return driver_data pointer
1073 * @teedev:     Device containing the driver_data pointer
1074 * @returns the driver_data pointer supplied to tee_register().
1075 */
1076void *tee_get_drvdata(struct tee_device *teedev)
1077{
1078        return dev_get_drvdata(&teedev->dev);
1079}
1080EXPORT_SYMBOL_GPL(tee_get_drvdata);
1081
1082struct match_dev_data {
1083        struct tee_ioctl_version_data *vers;
1084        const void *data;
1085        int (*match)(struct tee_ioctl_version_data *, const void *);
1086};
1087
1088static int match_dev(struct device *dev, const void *data)
1089{
1090        const struct match_dev_data *match_data = data;
1091        struct tee_device *teedev = container_of(dev, struct tee_device, dev);
1092
1093        teedev->desc->ops->get_version(teedev, match_data->vers);
1094        return match_data->match(match_data->vers, match_data->data);
1095}
1096
1097struct tee_context *
1098tee_client_open_context(struct tee_context *start,
1099                        int (*match)(struct tee_ioctl_version_data *,
1100                                     const void *),
1101                        const void *data, struct tee_ioctl_version_data *vers)
1102{
1103        struct device *dev = NULL;
1104        struct device *put_dev = NULL;
1105        struct tee_context *ctx = NULL;
1106        struct tee_ioctl_version_data v;
1107        struct match_dev_data match_data = { vers ? vers : &v, data, match };
1108
1109        if (start)
1110                dev = &start->teedev->dev;
1111
1112        do {
1113                dev = class_find_device(tee_class, dev, &match_data, match_dev);
1114                if (!dev) {
1115                        ctx = ERR_PTR(-ENOENT);
1116                        break;
1117                }
1118
1119                put_device(put_dev);
1120                put_dev = dev;
1121
1122                ctx = teedev_open(container_of(dev, struct tee_device, dev));
1123        } while (IS_ERR(ctx) && PTR_ERR(ctx) != -ENOMEM);
1124
1125        put_device(put_dev);
1126        /*
1127         * Default behaviour for in kernel client is to not wait for
1128         * tee-supplicant if not present for any requests in this context.
1129         * Also this flag could be configured again before call to
1130         * tee_client_open_session() if any in kernel client requires
1131         * different behaviour.
1132         */
1133        if (!IS_ERR(ctx))
1134                ctx->supp_nowait = true;
1135
1136        return ctx;
1137}
1138EXPORT_SYMBOL_GPL(tee_client_open_context);
1139
1140void tee_client_close_context(struct tee_context *ctx)
1141{
1142        teedev_close_context(ctx);
1143}
1144EXPORT_SYMBOL_GPL(tee_client_close_context);
1145
1146void tee_client_get_version(struct tee_context *ctx,
1147                            struct tee_ioctl_version_data *vers)
1148{
1149        ctx->teedev->desc->ops->get_version(ctx->teedev, vers);
1150}
1151EXPORT_SYMBOL_GPL(tee_client_get_version);
1152
1153int tee_client_open_session(struct tee_context *ctx,
1154                            struct tee_ioctl_open_session_arg *arg,
1155                            struct tee_param *param)
1156{
1157        if (!ctx->teedev->desc->ops->open_session)
1158                return -EINVAL;
1159        return ctx->teedev->desc->ops->open_session(ctx, arg, param);
1160}
1161EXPORT_SYMBOL_GPL(tee_client_open_session);
1162
1163int tee_client_close_session(struct tee_context *ctx, u32 session)
1164{
1165        if (!ctx->teedev->desc->ops->close_session)
1166                return -EINVAL;
1167        return ctx->teedev->desc->ops->close_session(ctx, session);
1168}
1169EXPORT_SYMBOL_GPL(tee_client_close_session);
1170
1171int tee_client_invoke_func(struct tee_context *ctx,
1172                           struct tee_ioctl_invoke_arg *arg,
1173                           struct tee_param *param)
1174{
1175        if (!ctx->teedev->desc->ops->invoke_func)
1176                return -EINVAL;
1177        return ctx->teedev->desc->ops->invoke_func(ctx, arg, param);
1178}
1179EXPORT_SYMBOL_GPL(tee_client_invoke_func);
1180
1181int tee_client_cancel_req(struct tee_context *ctx,
1182                          struct tee_ioctl_cancel_arg *arg)
1183{
1184        if (!ctx->teedev->desc->ops->cancel_req)
1185                return -EINVAL;
1186        return ctx->teedev->desc->ops->cancel_req(ctx, arg->cancel_id,
1187                                                  arg->session);
1188}
1189
1190static int tee_client_device_match(struct device *dev,
1191                                   struct device_driver *drv)
1192{
1193        const struct tee_client_device_id *id_table;
1194        struct tee_client_device *tee_device;
1195
1196        id_table = to_tee_client_driver(drv)->id_table;
1197        tee_device = to_tee_client_device(dev);
1198
1199        while (!uuid_is_null(&id_table->uuid)) {
1200                if (uuid_equal(&tee_device->id.uuid, &id_table->uuid))
1201                        return 1;
1202                id_table++;
1203        }
1204
1205        return 0;
1206}
1207
1208static int tee_client_device_uevent(struct device *dev,
1209                                    struct kobj_uevent_env *env)
1210{
1211        uuid_t *dev_id = &to_tee_client_device(dev)->id.uuid;
1212
1213        return add_uevent_var(env, "MODALIAS=tee:%pUb", dev_id);
1214}
1215
1216struct bus_type tee_bus_type = {
1217        .name           = "tee",
1218        .match          = tee_client_device_match,
1219        .uevent         = tee_client_device_uevent,
1220};
1221EXPORT_SYMBOL_GPL(tee_bus_type);
1222
1223static int __init tee_init(void)
1224{
1225        int rc;
1226
1227        tee_class = class_create(THIS_MODULE, "tee");
1228        if (IS_ERR(tee_class)) {
1229                pr_err("couldn't create class\n");
1230                return PTR_ERR(tee_class);
1231        }
1232
1233        rc = alloc_chrdev_region(&tee_devt, 0, TEE_NUM_DEVICES, "tee");
1234        if (rc) {
1235                pr_err("failed to allocate char dev region\n");
1236                goto out_unreg_class;
1237        }
1238
1239        rc = bus_register(&tee_bus_type);
1240        if (rc) {
1241                pr_err("failed to register tee bus\n");
1242                goto out_unreg_chrdev;
1243        }
1244
1245        return 0;
1246
1247out_unreg_chrdev:
1248        unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1249out_unreg_class:
1250        class_destroy(tee_class);
1251        tee_class = NULL;
1252
1253        return rc;
1254}
1255
1256static void __exit tee_exit(void)
1257{
1258        bus_unregister(&tee_bus_type);
1259        unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1260        class_destroy(tee_class);
1261        tee_class = NULL;
1262}
1263
1264subsys_initcall(tee_init);
1265module_exit(tee_exit);
1266
1267MODULE_AUTHOR("Linaro");
1268MODULE_DESCRIPTION("TEE Driver");
1269MODULE_VERSION("1.0");
1270MODULE_LICENSE("GPL v2");
1271