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/overflow.h>
14 #include <linux/slab.h>
15 #include <linux/tee_core.h>
16 #include <linux/uaccess.h>
17 #include <crypto/hash.h>
18 #include <crypto/sha1.h>
19 #include "tee_private.h"
20
21 #define TEE_NUM_DEVICES 32
22
23 #define TEE_IOCTL_PARAM_SIZE(x) (size_mul(sizeof(struct tee_param), (x)))
24
25 #define TEE_UUID_NS_NAME_SIZE 128
26
27 /*
28 * TEE Client UUID name space identifier (UUIDv4)
29 *
30 * Value here is random UUID that is allocated as name space identifier for
31 * forming Client UUID's for TEE environment using UUIDv5 scheme.
32 */
33 static const uuid_t tee_client_uuid_ns = UUID_INIT(0x58ac9ca0, 0x2086, 0x4683,
34 0xa1, 0xb8, 0xec, 0x4b,
35 0xc0, 0x8e, 0x01, 0xb6);
36
37 /*
38 * Unprivileged devices in the lower half range and privileged devices in
39 * the upper half range.
40 */
41 static DECLARE_BITMAP(dev_mask, TEE_NUM_DEVICES);
42 static DEFINE_SPINLOCK(driver_lock);
43
44 static const struct class tee_class;
45 static dev_t tee_devt;
46
teedev_open(struct tee_device * teedev)47 struct tee_context *teedev_open(struct tee_device *teedev)
48 {
49 int rc;
50 struct tee_context *ctx;
51
52 if (!tee_device_get(teedev))
53 return ERR_PTR(-EINVAL);
54
55 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
56 if (!ctx) {
57 rc = -ENOMEM;
58 goto err;
59 }
60
61 kref_init(&ctx->refcount);
62 ctx->teedev = teedev;
63 rc = teedev->desc->ops->open(ctx);
64 if (rc)
65 goto err;
66
67 return ctx;
68 err:
69 kfree(ctx);
70 tee_device_put(teedev);
71 return ERR_PTR(rc);
72
73 }
74 EXPORT_SYMBOL_GPL(teedev_open);
75
teedev_ctx_get(struct tee_context * ctx)76 void teedev_ctx_get(struct tee_context *ctx)
77 {
78 if (ctx->releasing)
79 return;
80
81 kref_get(&ctx->refcount);
82 }
83
teedev_ctx_release(struct kref * ref)84 static void teedev_ctx_release(struct kref *ref)
85 {
86 struct tee_context *ctx = container_of(ref, struct tee_context,
87 refcount);
88 ctx->releasing = true;
89 ctx->teedev->desc->ops->release(ctx);
90 kfree(ctx);
91 }
92
teedev_ctx_put(struct tee_context * ctx)93 void teedev_ctx_put(struct tee_context *ctx)
94 {
95 if (ctx->releasing)
96 return;
97
98 kref_put(&ctx->refcount, teedev_ctx_release);
99 }
100
teedev_close_context(struct tee_context * ctx)101 void teedev_close_context(struct tee_context *ctx)
102 {
103 struct tee_device *teedev = ctx->teedev;
104
105 teedev_ctx_put(ctx);
106 tee_device_put(teedev);
107 }
108 EXPORT_SYMBOL_GPL(teedev_close_context);
109
tee_open(struct inode * inode,struct file * filp)110 static int tee_open(struct inode *inode, struct file *filp)
111 {
112 struct tee_context *ctx;
113
114 ctx = teedev_open(container_of(inode->i_cdev, struct tee_device, cdev));
115 if (IS_ERR(ctx))
116 return PTR_ERR(ctx);
117
118 /*
119 * Default user-space behaviour is to wait for tee-supplicant
120 * if not present for any requests in this context.
121 */
122 ctx->supp_nowait = false;
123 filp->private_data = ctx;
124 return 0;
125 }
126
tee_release(struct inode * inode,struct file * filp)127 static int tee_release(struct inode *inode, struct file *filp)
128 {
129 teedev_close_context(filp->private_data);
130 return 0;
131 }
132
133 /**
134 * uuid_v5() - Calculate UUIDv5
135 * @uuid: Resulting UUID
136 * @ns: Name space ID for UUIDv5 function
137 * @name: Name for UUIDv5 function
138 * @size: Size of name
139 *
140 * UUIDv5 is specific in RFC 4122.
141 *
142 * This implements section (for SHA-1):
143 * 4.3. Algorithm for Creating a Name-Based UUID
144 */
uuid_v5(uuid_t * uuid,const uuid_t * ns,const void * name,size_t size)145 static int uuid_v5(uuid_t *uuid, const uuid_t *ns, const void *name,
146 size_t size)
147 {
148 unsigned char hash[SHA1_DIGEST_SIZE];
149 struct crypto_shash *shash = NULL;
150 struct shash_desc *desc = NULL;
151 int rc;
152
153 shash = crypto_alloc_shash("sha1", 0, 0);
154 if (IS_ERR(shash)) {
155 rc = PTR_ERR(shash);
156 pr_err("shash(sha1) allocation failed\n");
157 return rc;
158 }
159
160 desc = kzalloc(sizeof(*desc) + crypto_shash_descsize(shash),
161 GFP_KERNEL);
162 if (!desc) {
163 rc = -ENOMEM;
164 goto out_free_shash;
165 }
166
167 desc->tfm = shash;
168
169 rc = crypto_shash_init(desc);
170 if (rc < 0)
171 goto out_free_desc;
172
173 rc = crypto_shash_update(desc, (const u8 *)ns, sizeof(*ns));
174 if (rc < 0)
175 goto out_free_desc;
176
177 rc = crypto_shash_update(desc, (const u8 *)name, size);
178 if (rc < 0)
179 goto out_free_desc;
180
181 rc = crypto_shash_final(desc, hash);
182 if (rc < 0)
183 goto out_free_desc;
184
185 memcpy(uuid->b, hash, UUID_SIZE);
186
187 /* Tag for version 5 */
188 uuid->b[6] = (hash[6] & 0x0F) | 0x50;
189 uuid->b[8] = (hash[8] & 0x3F) | 0x80;
190
191 out_free_desc:
192 kfree(desc);
193
194 out_free_shash:
195 crypto_free_shash(shash);
196 return rc;
197 }
198
tee_session_calc_client_uuid(uuid_t * uuid,u32 connection_method,const u8 connection_data[TEE_IOCTL_UUID_LEN])199 int tee_session_calc_client_uuid(uuid_t *uuid, u32 connection_method,
200 const u8 connection_data[TEE_IOCTL_UUID_LEN])
201 {
202 gid_t ns_grp = (gid_t)-1;
203 kgid_t grp = INVALID_GID;
204 char *name = NULL;
205 int name_len;
206 int rc;
207
208 if (connection_method == TEE_IOCTL_LOGIN_PUBLIC ||
209 connection_method == TEE_IOCTL_LOGIN_REE_KERNEL) {
210 /* Nil UUID to be passed to TEE environment */
211 uuid_copy(uuid, &uuid_null);
212 return 0;
213 }
214
215 /*
216 * In Linux environment client UUID is based on UUIDv5.
217 *
218 * Determine client UUID with following semantics for 'name':
219 *
220 * For TEEC_LOGIN_USER:
221 * uid=<uid>
222 *
223 * For TEEC_LOGIN_GROUP:
224 * gid=<gid>
225 *
226 */
227
228 name = kzalloc(TEE_UUID_NS_NAME_SIZE, GFP_KERNEL);
229 if (!name)
230 return -ENOMEM;
231
232 switch (connection_method) {
233 case TEE_IOCTL_LOGIN_USER:
234 name_len = snprintf(name, TEE_UUID_NS_NAME_SIZE, "uid=%x",
235 current_euid().val);
236 if (name_len >= TEE_UUID_NS_NAME_SIZE) {
237 rc = -E2BIG;
238 goto out_free_name;
239 }
240 break;
241
242 case TEE_IOCTL_LOGIN_GROUP:
243 memcpy(&ns_grp, connection_data, sizeof(gid_t));
244 grp = make_kgid(current_user_ns(), ns_grp);
245 if (!gid_valid(grp) || !in_egroup_p(grp)) {
246 rc = -EPERM;
247 goto out_free_name;
248 }
249
250 name_len = snprintf(name, TEE_UUID_NS_NAME_SIZE, "gid=%x",
251 grp.val);
252 if (name_len >= TEE_UUID_NS_NAME_SIZE) {
253 rc = -E2BIG;
254 goto out_free_name;
255 }
256 break;
257
258 default:
259 rc = -EINVAL;
260 goto out_free_name;
261 }
262
263 rc = uuid_v5(uuid, &tee_client_uuid_ns, name, name_len);
264 out_free_name:
265 kfree(name);
266
267 return rc;
268 }
269 EXPORT_SYMBOL_GPL(tee_session_calc_client_uuid);
270
tee_ioctl_version(struct tee_context * ctx,struct tee_ioctl_version_data __user * uvers)271 static int tee_ioctl_version(struct tee_context *ctx,
272 struct tee_ioctl_version_data __user *uvers)
273 {
274 struct tee_ioctl_version_data vers;
275
276 ctx->teedev->desc->ops->get_version(ctx->teedev, &vers);
277
278 if (ctx->teedev->desc->flags & TEE_DESC_PRIVILEGED)
279 vers.gen_caps |= TEE_GEN_CAP_PRIVILEGED;
280
281 if (copy_to_user(uvers, &vers, sizeof(vers)))
282 return -EFAULT;
283
284 return 0;
285 }
286
tee_ioctl_shm_alloc(struct tee_context * ctx,struct tee_ioctl_shm_alloc_data __user * udata)287 static int tee_ioctl_shm_alloc(struct tee_context *ctx,
288 struct tee_ioctl_shm_alloc_data __user *udata)
289 {
290 long ret;
291 struct tee_ioctl_shm_alloc_data data;
292 struct tee_shm *shm;
293
294 if (copy_from_user(&data, udata, sizeof(data)))
295 return -EFAULT;
296
297 /* Currently no input flags are supported */
298 if (data.flags)
299 return -EINVAL;
300
301 shm = tee_shm_alloc_user_buf(ctx, data.size);
302 if (IS_ERR(shm))
303 return PTR_ERR(shm);
304
305 data.id = shm->id;
306 data.size = shm->size;
307
308 if (copy_to_user(udata, &data, sizeof(data)))
309 ret = -EFAULT;
310 else
311 ret = tee_shm_get_fd(shm);
312
313 /*
314 * When user space closes the file descriptor the shared memory
315 * should be freed or if tee_shm_get_fd() failed then it will
316 * be freed immediately.
317 */
318 tee_shm_put(shm);
319 return ret;
320 }
321
322 static int
tee_ioctl_shm_register(struct tee_context * ctx,struct tee_ioctl_shm_register_data __user * udata)323 tee_ioctl_shm_register(struct tee_context *ctx,
324 struct tee_ioctl_shm_register_data __user *udata)
325 {
326 long ret;
327 struct tee_ioctl_shm_register_data data;
328 struct tee_shm *shm;
329
330 if (copy_from_user(&data, udata, sizeof(data)))
331 return -EFAULT;
332
333 /* Currently no input flags are supported */
334 if (data.flags)
335 return -EINVAL;
336
337 shm = tee_shm_register_user_buf(ctx, data.addr, data.length);
338 if (IS_ERR(shm))
339 return PTR_ERR(shm);
340
341 data.id = shm->id;
342 data.length = shm->size;
343
344 if (copy_to_user(udata, &data, sizeof(data)))
345 ret = -EFAULT;
346 else
347 ret = tee_shm_get_fd(shm);
348 /*
349 * When user space closes the file descriptor the shared memory
350 * should be freed or if tee_shm_get_fd() failed then it will
351 * be freed immediately.
352 */
353 tee_shm_put(shm);
354 return ret;
355 }
356
params_from_user(struct tee_context * ctx,struct tee_param * params,size_t num_params,struct tee_ioctl_param __user * uparams)357 static int params_from_user(struct tee_context *ctx, struct tee_param *params,
358 size_t num_params,
359 struct tee_ioctl_param __user *uparams)
360 {
361 size_t n;
362
363 for (n = 0; n < num_params; n++) {
364 struct tee_shm *shm;
365 struct tee_ioctl_param ip;
366
367 if (copy_from_user(&ip, uparams + n, sizeof(ip)))
368 return -EFAULT;
369
370 /* All unused attribute bits has to be zero */
371 if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
372 return -EINVAL;
373
374 params[n].attr = ip.attr;
375 switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
376 case TEE_IOCTL_PARAM_ATTR_TYPE_NONE:
377 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
378 break;
379 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
380 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
381 params[n].u.value.a = ip.a;
382 params[n].u.value.b = ip.b;
383 params[n].u.value.c = ip.c;
384 break;
385 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
386 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
387 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
388 /*
389 * If a NULL pointer is passed to a TA in the TEE,
390 * the ip.c IOCTL parameters is set to TEE_MEMREF_NULL
391 * indicating a NULL memory reference.
392 */
393 if (ip.c != TEE_MEMREF_NULL) {
394 /*
395 * If we fail to get a pointer to a shared
396 * memory object (and increase the ref count)
397 * from an identifier we return an error. All
398 * pointers that has been added in params have
399 * an increased ref count. It's the callers
400 * responibility to do tee_shm_put() on all
401 * resolved pointers.
402 */
403 shm = tee_shm_get_from_id(ctx, ip.c);
404 if (IS_ERR(shm))
405 return PTR_ERR(shm);
406
407 /*
408 * Ensure offset + size does not overflow
409 * offset and does not overflow the size of
410 * the referred shared memory object.
411 */
412 if ((ip.a + ip.b) < ip.a ||
413 (ip.a + ip.b) > shm->size) {
414 tee_shm_put(shm);
415 return -EINVAL;
416 }
417 } else if (ctx->cap_memref_null) {
418 /* Pass NULL pointer to OP-TEE */
419 shm = NULL;
420 } else {
421 return -EINVAL;
422 }
423
424 params[n].u.memref.shm_offs = ip.a;
425 params[n].u.memref.size = ip.b;
426 params[n].u.memref.shm = shm;
427 break;
428 default:
429 /* Unknown attribute */
430 return -EINVAL;
431 }
432 }
433 return 0;
434 }
435
params_to_user(struct tee_ioctl_param __user * uparams,size_t num_params,struct tee_param * params)436 static int params_to_user(struct tee_ioctl_param __user *uparams,
437 size_t num_params, struct tee_param *params)
438 {
439 size_t n;
440
441 for (n = 0; n < num_params; n++) {
442 struct tee_ioctl_param __user *up = uparams + n;
443 struct tee_param *p = params + n;
444
445 switch (p->attr) {
446 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
447 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
448 if (put_user(p->u.value.a, &up->a) ||
449 put_user(p->u.value.b, &up->b) ||
450 put_user(p->u.value.c, &up->c))
451 return -EFAULT;
452 break;
453 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
454 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
455 if (put_user((u64)p->u.memref.size, &up->b))
456 return -EFAULT;
457 break;
458 default:
459 break;
460 }
461 }
462 return 0;
463 }
464
tee_ioctl_open_session(struct tee_context * ctx,struct tee_ioctl_buf_data __user * ubuf)465 static int tee_ioctl_open_session(struct tee_context *ctx,
466 struct tee_ioctl_buf_data __user *ubuf)
467 {
468 int rc;
469 size_t n;
470 struct tee_ioctl_buf_data buf;
471 struct tee_ioctl_open_session_arg __user *uarg;
472 struct tee_ioctl_open_session_arg arg;
473 struct tee_ioctl_param __user *uparams = NULL;
474 struct tee_param *params = NULL;
475 bool have_session = false;
476
477 if (!ctx->teedev->desc->ops->open_session)
478 return -EINVAL;
479
480 if (copy_from_user(&buf, ubuf, sizeof(buf)))
481 return -EFAULT;
482
483 if (buf.buf_len > TEE_MAX_ARG_SIZE ||
484 buf.buf_len < sizeof(struct tee_ioctl_open_session_arg))
485 return -EINVAL;
486
487 uarg = u64_to_user_ptr(buf.buf_ptr);
488 if (copy_from_user(&arg, uarg, sizeof(arg)))
489 return -EFAULT;
490
491 if (size_add(sizeof(arg), TEE_IOCTL_PARAM_SIZE(arg.num_params)) != buf.buf_len)
492 return -EINVAL;
493
494 if (arg.num_params) {
495 params = kcalloc(arg.num_params, sizeof(struct tee_param),
496 GFP_KERNEL);
497 if (!params)
498 return -ENOMEM;
499 uparams = uarg->params;
500 rc = params_from_user(ctx, params, arg.num_params, uparams);
501 if (rc)
502 goto out;
503 }
504
505 if (arg.clnt_login >= TEE_IOCTL_LOGIN_REE_KERNEL_MIN &&
506 arg.clnt_login <= TEE_IOCTL_LOGIN_REE_KERNEL_MAX) {
507 pr_debug("login method not allowed for user-space client\n");
508 rc = -EPERM;
509 goto out;
510 }
511
512 rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params);
513 if (rc)
514 goto out;
515 have_session = true;
516
517 if (put_user(arg.session, &uarg->session) ||
518 put_user(arg.ret, &uarg->ret) ||
519 put_user(arg.ret_origin, &uarg->ret_origin)) {
520 rc = -EFAULT;
521 goto out;
522 }
523 rc = params_to_user(uparams, arg.num_params, params);
524 out:
525 /*
526 * If we've succeeded to open the session but failed to communicate
527 * it back to user space, close the session again to avoid leakage.
528 */
529 if (rc && have_session && ctx->teedev->desc->ops->close_session)
530 ctx->teedev->desc->ops->close_session(ctx, arg.session);
531
532 if (params) {
533 /* Decrease ref count for all valid shared memory pointers */
534 for (n = 0; n < arg.num_params; n++)
535 if (tee_param_is_memref(params + n) &&
536 params[n].u.memref.shm)
537 tee_shm_put(params[n].u.memref.shm);
538 kfree(params);
539 }
540
541 return rc;
542 }
543
tee_ioctl_invoke(struct tee_context * ctx,struct tee_ioctl_buf_data __user * ubuf)544 static int tee_ioctl_invoke(struct tee_context *ctx,
545 struct tee_ioctl_buf_data __user *ubuf)
546 {
547 int rc;
548 size_t n;
549 struct tee_ioctl_buf_data buf;
550 struct tee_ioctl_invoke_arg __user *uarg;
551 struct tee_ioctl_invoke_arg arg;
552 struct tee_ioctl_param __user *uparams = NULL;
553 struct tee_param *params = NULL;
554
555 if (!ctx->teedev->desc->ops->invoke_func)
556 return -EINVAL;
557
558 if (copy_from_user(&buf, ubuf, sizeof(buf)))
559 return -EFAULT;
560
561 if (buf.buf_len > TEE_MAX_ARG_SIZE ||
562 buf.buf_len < sizeof(struct tee_ioctl_invoke_arg))
563 return -EINVAL;
564
565 uarg = u64_to_user_ptr(buf.buf_ptr);
566 if (copy_from_user(&arg, uarg, sizeof(arg)))
567 return -EFAULT;
568
569 if (size_add(sizeof(arg), TEE_IOCTL_PARAM_SIZE(arg.num_params)) != buf.buf_len)
570 return -EINVAL;
571
572 if (arg.num_params) {
573 params = kcalloc(arg.num_params, sizeof(struct tee_param),
574 GFP_KERNEL);
575 if (!params)
576 return -ENOMEM;
577 uparams = uarg->params;
578 rc = params_from_user(ctx, params, arg.num_params, uparams);
579 if (rc)
580 goto out;
581 }
582
583 rc = ctx->teedev->desc->ops->invoke_func(ctx, &arg, params);
584 if (rc)
585 goto out;
586
587 if (put_user(arg.ret, &uarg->ret) ||
588 put_user(arg.ret_origin, &uarg->ret_origin)) {
589 rc = -EFAULT;
590 goto out;
591 }
592 rc = params_to_user(uparams, arg.num_params, params);
593 out:
594 if (params) {
595 /* Decrease ref count for all valid shared memory pointers */
596 for (n = 0; n < arg.num_params; n++)
597 if (tee_param_is_memref(params + n) &&
598 params[n].u.memref.shm)
599 tee_shm_put(params[n].u.memref.shm);
600 kfree(params);
601 }
602 return rc;
603 }
604
tee_ioctl_cancel(struct tee_context * ctx,struct tee_ioctl_cancel_arg __user * uarg)605 static int tee_ioctl_cancel(struct tee_context *ctx,
606 struct tee_ioctl_cancel_arg __user *uarg)
607 {
608 struct tee_ioctl_cancel_arg arg;
609
610 if (!ctx->teedev->desc->ops->cancel_req)
611 return -EINVAL;
612
613 if (copy_from_user(&arg, uarg, sizeof(arg)))
614 return -EFAULT;
615
616 return ctx->teedev->desc->ops->cancel_req(ctx, arg.cancel_id,
617 arg.session);
618 }
619
620 static int
tee_ioctl_close_session(struct tee_context * ctx,struct tee_ioctl_close_session_arg __user * uarg)621 tee_ioctl_close_session(struct tee_context *ctx,
622 struct tee_ioctl_close_session_arg __user *uarg)
623 {
624 struct tee_ioctl_close_session_arg arg;
625
626 if (!ctx->teedev->desc->ops->close_session)
627 return -EINVAL;
628
629 if (copy_from_user(&arg, uarg, sizeof(arg)))
630 return -EFAULT;
631
632 return ctx->teedev->desc->ops->close_session(ctx, arg.session);
633 }
634
params_to_supp(struct tee_context * ctx,struct tee_ioctl_param __user * uparams,size_t num_params,struct tee_param * params)635 static int params_to_supp(struct tee_context *ctx,
636 struct tee_ioctl_param __user *uparams,
637 size_t num_params, struct tee_param *params)
638 {
639 size_t n;
640
641 for (n = 0; n < num_params; n++) {
642 struct tee_ioctl_param ip;
643 struct tee_param *p = params + n;
644
645 ip.attr = p->attr;
646 switch (p->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
647 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
648 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
649 ip.a = p->u.value.a;
650 ip.b = p->u.value.b;
651 ip.c = p->u.value.c;
652 break;
653 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
654 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
655 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
656 ip.b = p->u.memref.size;
657 if (!p->u.memref.shm) {
658 ip.a = 0;
659 ip.c = (u64)-1; /* invalid shm id */
660 break;
661 }
662 ip.a = p->u.memref.shm_offs;
663 ip.c = p->u.memref.shm->id;
664 break;
665 default:
666 ip.a = 0;
667 ip.b = 0;
668 ip.c = 0;
669 break;
670 }
671
672 if (copy_to_user(uparams + n, &ip, sizeof(ip)))
673 return -EFAULT;
674 }
675
676 return 0;
677 }
678
tee_ioctl_supp_recv(struct tee_context * ctx,struct tee_ioctl_buf_data __user * ubuf)679 static int tee_ioctl_supp_recv(struct tee_context *ctx,
680 struct tee_ioctl_buf_data __user *ubuf)
681 {
682 int rc;
683 struct tee_ioctl_buf_data buf;
684 struct tee_iocl_supp_recv_arg __user *uarg;
685 struct tee_param *params;
686 u32 num_params;
687 u32 func;
688
689 if (!ctx->teedev->desc->ops->supp_recv)
690 return -EINVAL;
691
692 if (copy_from_user(&buf, ubuf, sizeof(buf)))
693 return -EFAULT;
694
695 if (buf.buf_len > TEE_MAX_ARG_SIZE ||
696 buf.buf_len < sizeof(struct tee_iocl_supp_recv_arg))
697 return -EINVAL;
698
699 uarg = u64_to_user_ptr(buf.buf_ptr);
700 if (get_user(num_params, &uarg->num_params))
701 return -EFAULT;
702
703 if (size_add(sizeof(*uarg), TEE_IOCTL_PARAM_SIZE(num_params)) != buf.buf_len)
704 return -EINVAL;
705
706 params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
707 if (!params)
708 return -ENOMEM;
709
710 rc = params_from_user(ctx, params, num_params, uarg->params);
711 if (rc)
712 goto out;
713
714 rc = ctx->teedev->desc->ops->supp_recv(ctx, &func, &num_params, params);
715 if (rc)
716 goto out;
717
718 if (put_user(func, &uarg->func) ||
719 put_user(num_params, &uarg->num_params)) {
720 rc = -EFAULT;
721 goto out;
722 }
723
724 rc = params_to_supp(ctx, uarg->params, num_params, params);
725 out:
726 kfree(params);
727 return rc;
728 }
729
params_from_supp(struct tee_param * params,size_t num_params,struct tee_ioctl_param __user * uparams)730 static int params_from_supp(struct tee_param *params, size_t num_params,
731 struct tee_ioctl_param __user *uparams)
732 {
733 size_t n;
734
735 for (n = 0; n < num_params; n++) {
736 struct tee_param *p = params + n;
737 struct tee_ioctl_param ip;
738
739 if (copy_from_user(&ip, uparams + n, sizeof(ip)))
740 return -EFAULT;
741
742 /* All unused attribute bits has to be zero */
743 if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
744 return -EINVAL;
745
746 p->attr = ip.attr;
747 switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
748 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
749 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
750 /* Only out and in/out values can be updated */
751 p->u.value.a = ip.a;
752 p->u.value.b = ip.b;
753 p->u.value.c = ip.c;
754 break;
755 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
756 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
757 /*
758 * Only the size of the memref can be updated.
759 * Since we don't have access to the original
760 * parameters here, only store the supplied size.
761 * The driver will copy the updated size into the
762 * original parameters.
763 */
764 p->u.memref.shm = NULL;
765 p->u.memref.shm_offs = 0;
766 p->u.memref.size = ip.b;
767 break;
768 default:
769 memset(&p->u, 0, sizeof(p->u));
770 break;
771 }
772 }
773 return 0;
774 }
775
tee_ioctl_supp_send(struct tee_context * ctx,struct tee_ioctl_buf_data __user * ubuf)776 static int tee_ioctl_supp_send(struct tee_context *ctx,
777 struct tee_ioctl_buf_data __user *ubuf)
778 {
779 long rc;
780 struct tee_ioctl_buf_data buf;
781 struct tee_iocl_supp_send_arg __user *uarg;
782 struct tee_param *params;
783 u32 num_params;
784 u32 ret;
785
786 /* Not valid for this driver */
787 if (!ctx->teedev->desc->ops->supp_send)
788 return -EINVAL;
789
790 if (copy_from_user(&buf, ubuf, sizeof(buf)))
791 return -EFAULT;
792
793 if (buf.buf_len > TEE_MAX_ARG_SIZE ||
794 buf.buf_len < sizeof(struct tee_iocl_supp_send_arg))
795 return -EINVAL;
796
797 uarg = u64_to_user_ptr(buf.buf_ptr);
798 if (get_user(ret, &uarg->ret) ||
799 get_user(num_params, &uarg->num_params))
800 return -EFAULT;
801
802 if (size_add(sizeof(*uarg), TEE_IOCTL_PARAM_SIZE(num_params)) > buf.buf_len)
803 return -EINVAL;
804
805 params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
806 if (!params)
807 return -ENOMEM;
808
809 rc = params_from_supp(params, num_params, uarg->params);
810 if (rc)
811 goto out;
812
813 rc = ctx->teedev->desc->ops->supp_send(ctx, ret, num_params, params);
814 out:
815 kfree(params);
816 return rc;
817 }
818
tee_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)819 static long tee_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
820 {
821 struct tee_context *ctx = filp->private_data;
822 void __user *uarg = (void __user *)arg;
823
824 switch (cmd) {
825 case TEE_IOC_VERSION:
826 return tee_ioctl_version(ctx, uarg);
827 case TEE_IOC_SHM_ALLOC:
828 return tee_ioctl_shm_alloc(ctx, uarg);
829 case TEE_IOC_SHM_REGISTER:
830 return tee_ioctl_shm_register(ctx, uarg);
831 case TEE_IOC_OPEN_SESSION:
832 return tee_ioctl_open_session(ctx, uarg);
833 case TEE_IOC_INVOKE:
834 return tee_ioctl_invoke(ctx, uarg);
835 case TEE_IOC_CANCEL:
836 return tee_ioctl_cancel(ctx, uarg);
837 case TEE_IOC_CLOSE_SESSION:
838 return tee_ioctl_close_session(ctx, uarg);
839 case TEE_IOC_SUPPL_RECV:
840 return tee_ioctl_supp_recv(ctx, uarg);
841 case TEE_IOC_SUPPL_SEND:
842 return tee_ioctl_supp_send(ctx, uarg);
843 default:
844 return -EINVAL;
845 }
846 }
847
848 static const struct file_operations tee_fops = {
849 .owner = THIS_MODULE,
850 .open = tee_open,
851 .release = tee_release,
852 .unlocked_ioctl = tee_ioctl,
853 .compat_ioctl = compat_ptr_ioctl,
854 };
855
tee_release_device(struct device * dev)856 static void tee_release_device(struct device *dev)
857 {
858 struct tee_device *teedev = container_of(dev, struct tee_device, dev);
859
860 spin_lock(&driver_lock);
861 clear_bit(teedev->id, dev_mask);
862 spin_unlock(&driver_lock);
863 mutex_destroy(&teedev->mutex);
864 idr_destroy(&teedev->idr);
865 kfree(teedev);
866 }
867
868 /**
869 * tee_device_alloc() - Allocate a new struct tee_device instance
870 * @teedesc: Descriptor for this driver
871 * @dev: Parent device for this device
872 * @pool: Shared memory pool, NULL if not used
873 * @driver_data: Private driver data for this device
874 *
875 * Allocates a new struct tee_device instance. The device is
876 * removed by tee_device_unregister().
877 *
878 * @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
879 */
tee_device_alloc(const struct tee_desc * teedesc,struct device * dev,struct tee_shm_pool * pool,void * driver_data)880 struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
881 struct device *dev,
882 struct tee_shm_pool *pool,
883 void *driver_data)
884 {
885 struct tee_device *teedev;
886 void *ret;
887 int rc, max_id;
888 int offs = 0;
889
890 if (!teedesc || !teedesc->name || !teedesc->ops ||
891 !teedesc->ops->get_version || !teedesc->ops->open ||
892 !teedesc->ops->release || !pool)
893 return ERR_PTR(-EINVAL);
894
895 teedev = kzalloc(sizeof(*teedev), GFP_KERNEL);
896 if (!teedev) {
897 ret = ERR_PTR(-ENOMEM);
898 goto err;
899 }
900
901 max_id = TEE_NUM_DEVICES / 2;
902
903 if (teedesc->flags & TEE_DESC_PRIVILEGED) {
904 offs = TEE_NUM_DEVICES / 2;
905 max_id = TEE_NUM_DEVICES;
906 }
907
908 spin_lock(&driver_lock);
909 teedev->id = find_next_zero_bit(dev_mask, max_id, offs);
910 if (teedev->id < max_id)
911 set_bit(teedev->id, dev_mask);
912 spin_unlock(&driver_lock);
913
914 if (teedev->id >= max_id) {
915 ret = ERR_PTR(-ENOMEM);
916 goto err;
917 }
918
919 snprintf(teedev->name, sizeof(teedev->name), "tee%s%d",
920 teedesc->flags & TEE_DESC_PRIVILEGED ? "priv" : "",
921 teedev->id - offs);
922
923 teedev->dev.class = &tee_class;
924 teedev->dev.release = tee_release_device;
925 teedev->dev.parent = dev;
926
927 teedev->dev.devt = MKDEV(MAJOR(tee_devt), teedev->id);
928
929 rc = dev_set_name(&teedev->dev, "%s", teedev->name);
930 if (rc) {
931 ret = ERR_PTR(rc);
932 goto err_devt;
933 }
934
935 cdev_init(&teedev->cdev, &tee_fops);
936 teedev->cdev.owner = teedesc->owner;
937
938 dev_set_drvdata(&teedev->dev, driver_data);
939 device_initialize(&teedev->dev);
940
941 /* 1 as tee_device_unregister() does one final tee_device_put() */
942 teedev->num_users = 1;
943 init_completion(&teedev->c_no_users);
944 mutex_init(&teedev->mutex);
945 idr_init(&teedev->idr);
946
947 teedev->desc = teedesc;
948 teedev->pool = pool;
949
950 return teedev;
951 err_devt:
952 unregister_chrdev_region(teedev->dev.devt, 1);
953 err:
954 pr_err("could not register %s driver\n",
955 teedesc->flags & TEE_DESC_PRIVILEGED ? "privileged" : "client");
956 if (teedev && teedev->id < TEE_NUM_DEVICES) {
957 spin_lock(&driver_lock);
958 clear_bit(teedev->id, dev_mask);
959 spin_unlock(&driver_lock);
960 }
961 kfree(teedev);
962 return ret;
963 }
964 EXPORT_SYMBOL_GPL(tee_device_alloc);
965
tee_device_set_dev_groups(struct tee_device * teedev,const struct attribute_group ** dev_groups)966 void tee_device_set_dev_groups(struct tee_device *teedev,
967 const struct attribute_group **dev_groups)
968 {
969 teedev->dev.groups = dev_groups;
970 }
971 EXPORT_SYMBOL_GPL(tee_device_set_dev_groups);
972
implementation_id_show(struct device * dev,struct device_attribute * attr,char * buf)973 static ssize_t implementation_id_show(struct device *dev,
974 struct device_attribute *attr, char *buf)
975 {
976 struct tee_device *teedev = container_of(dev, struct tee_device, dev);
977 struct tee_ioctl_version_data vers;
978
979 teedev->desc->ops->get_version(teedev, &vers);
980 return scnprintf(buf, PAGE_SIZE, "%d\n", vers.impl_id);
981 }
982 static DEVICE_ATTR_RO(implementation_id);
983
984 static struct attribute *tee_dev_attrs[] = {
985 &dev_attr_implementation_id.attr,
986 NULL
987 };
988
989 ATTRIBUTE_GROUPS(tee_dev);
990
991 static const struct class tee_class = {
992 .name = "tee",
993 .dev_groups = tee_dev_groups,
994 };
995
996 /**
997 * tee_device_register() - Registers a TEE device
998 * @teedev: Device to register
999 *
1000 * tee_device_unregister() need to be called to remove the @teedev if
1001 * this function fails.
1002 *
1003 * @returns < 0 on failure
1004 */
tee_device_register(struct tee_device * teedev)1005 int tee_device_register(struct tee_device *teedev)
1006 {
1007 int rc;
1008
1009 if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
1010 dev_err(&teedev->dev, "attempt to register twice\n");
1011 return -EINVAL;
1012 }
1013
1014 rc = cdev_device_add(&teedev->cdev, &teedev->dev);
1015 if (rc) {
1016 dev_err(&teedev->dev,
1017 "unable to cdev_device_add() %s, major %d, minor %d, err=%d\n",
1018 teedev->name, MAJOR(teedev->dev.devt),
1019 MINOR(teedev->dev.devt), rc);
1020 return rc;
1021 }
1022
1023 teedev->flags |= TEE_DEVICE_FLAG_REGISTERED;
1024 return 0;
1025 }
1026 EXPORT_SYMBOL_GPL(tee_device_register);
1027
tee_device_put(struct tee_device * teedev)1028 void tee_device_put(struct tee_device *teedev)
1029 {
1030 mutex_lock(&teedev->mutex);
1031 /* Shouldn't put in this state */
1032 if (!WARN_ON(!teedev->desc)) {
1033 teedev->num_users--;
1034 if (!teedev->num_users) {
1035 teedev->desc = NULL;
1036 complete(&teedev->c_no_users);
1037 }
1038 }
1039 mutex_unlock(&teedev->mutex);
1040 }
1041
tee_device_get(struct tee_device * teedev)1042 bool tee_device_get(struct tee_device *teedev)
1043 {
1044 mutex_lock(&teedev->mutex);
1045 if (!teedev->desc) {
1046 mutex_unlock(&teedev->mutex);
1047 return false;
1048 }
1049 teedev->num_users++;
1050 mutex_unlock(&teedev->mutex);
1051 return true;
1052 }
1053
1054 /**
1055 * tee_device_unregister() - Removes a TEE device
1056 * @teedev: Device to unregister
1057 *
1058 * This function should be called to remove the @teedev even if
1059 * tee_device_register() hasn't been called yet. Does nothing if
1060 * @teedev is NULL.
1061 */
tee_device_unregister(struct tee_device * teedev)1062 void tee_device_unregister(struct tee_device *teedev)
1063 {
1064 if (!teedev)
1065 return;
1066
1067 if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED)
1068 cdev_device_del(&teedev->cdev, &teedev->dev);
1069
1070 tee_device_put(teedev);
1071 wait_for_completion(&teedev->c_no_users);
1072
1073 /*
1074 * No need to take a mutex any longer now since teedev->desc was
1075 * set to NULL before teedev->c_no_users was completed.
1076 */
1077
1078 teedev->pool = NULL;
1079
1080 put_device(&teedev->dev);
1081 }
1082 EXPORT_SYMBOL_GPL(tee_device_unregister);
1083
1084 /**
1085 * tee_get_drvdata() - Return driver_data pointer
1086 * @teedev: Device containing the driver_data pointer
1087 * @returns the driver_data pointer supplied to tee_device_alloc().
1088 */
tee_get_drvdata(struct tee_device * teedev)1089 void *tee_get_drvdata(struct tee_device *teedev)
1090 {
1091 return dev_get_drvdata(&teedev->dev);
1092 }
1093 EXPORT_SYMBOL_GPL(tee_get_drvdata);
1094
1095 struct match_dev_data {
1096 struct tee_ioctl_version_data *vers;
1097 const void *data;
1098 int (*match)(struct tee_ioctl_version_data *, const void *);
1099 };
1100
match_dev(struct device * dev,const void * data)1101 static int match_dev(struct device *dev, const void *data)
1102 {
1103 const struct match_dev_data *match_data = data;
1104 struct tee_device *teedev = container_of(dev, struct tee_device, dev);
1105
1106 teedev->desc->ops->get_version(teedev, match_data->vers);
1107 return match_data->match(match_data->vers, match_data->data);
1108 }
1109
1110 struct tee_context *
tee_client_open_context(struct tee_context * start,int (* match)(struct tee_ioctl_version_data *,const void *),const void * data,struct tee_ioctl_version_data * vers)1111 tee_client_open_context(struct tee_context *start,
1112 int (*match)(struct tee_ioctl_version_data *,
1113 const void *),
1114 const void *data, struct tee_ioctl_version_data *vers)
1115 {
1116 struct device *dev = NULL;
1117 struct device *put_dev = NULL;
1118 struct tee_context *ctx = NULL;
1119 struct tee_ioctl_version_data v;
1120 struct match_dev_data match_data = { vers ? vers : &v, data, match };
1121
1122 if (start)
1123 dev = &start->teedev->dev;
1124
1125 do {
1126 dev = class_find_device(&tee_class, dev, &match_data, match_dev);
1127 if (!dev) {
1128 ctx = ERR_PTR(-ENOENT);
1129 break;
1130 }
1131
1132 put_device(put_dev);
1133 put_dev = dev;
1134
1135 ctx = teedev_open(container_of(dev, struct tee_device, dev));
1136 } while (IS_ERR(ctx) && PTR_ERR(ctx) != -ENOMEM);
1137
1138 put_device(put_dev);
1139 /*
1140 * Default behaviour for in kernel client is to not wait for
1141 * tee-supplicant if not present for any requests in this context.
1142 * Also this flag could be configured again before call to
1143 * tee_client_open_session() if any in kernel client requires
1144 * different behaviour.
1145 */
1146 if (!IS_ERR(ctx))
1147 ctx->supp_nowait = true;
1148
1149 return ctx;
1150 }
1151 EXPORT_SYMBOL_GPL(tee_client_open_context);
1152
tee_client_close_context(struct tee_context * ctx)1153 void tee_client_close_context(struct tee_context *ctx)
1154 {
1155 teedev_close_context(ctx);
1156 }
1157 EXPORT_SYMBOL_GPL(tee_client_close_context);
1158
tee_client_get_version(struct tee_context * ctx,struct tee_ioctl_version_data * vers)1159 void tee_client_get_version(struct tee_context *ctx,
1160 struct tee_ioctl_version_data *vers)
1161 {
1162 ctx->teedev->desc->ops->get_version(ctx->teedev, vers);
1163 }
1164 EXPORT_SYMBOL_GPL(tee_client_get_version);
1165
tee_client_open_session(struct tee_context * ctx,struct tee_ioctl_open_session_arg * arg,struct tee_param * param)1166 int tee_client_open_session(struct tee_context *ctx,
1167 struct tee_ioctl_open_session_arg *arg,
1168 struct tee_param *param)
1169 {
1170 if (!ctx->teedev->desc->ops->open_session)
1171 return -EINVAL;
1172 return ctx->teedev->desc->ops->open_session(ctx, arg, param);
1173 }
1174 EXPORT_SYMBOL_GPL(tee_client_open_session);
1175
tee_client_close_session(struct tee_context * ctx,u32 session)1176 int tee_client_close_session(struct tee_context *ctx, u32 session)
1177 {
1178 if (!ctx->teedev->desc->ops->close_session)
1179 return -EINVAL;
1180 return ctx->teedev->desc->ops->close_session(ctx, session);
1181 }
1182 EXPORT_SYMBOL_GPL(tee_client_close_session);
1183
tee_client_system_session(struct tee_context * ctx,u32 session)1184 int tee_client_system_session(struct tee_context *ctx, u32 session)
1185 {
1186 if (!ctx->teedev->desc->ops->system_session)
1187 return -EINVAL;
1188 return ctx->teedev->desc->ops->system_session(ctx, session);
1189 }
1190 EXPORT_SYMBOL_GPL(tee_client_system_session);
1191
tee_client_invoke_func(struct tee_context * ctx,struct tee_ioctl_invoke_arg * arg,struct tee_param * param)1192 int tee_client_invoke_func(struct tee_context *ctx,
1193 struct tee_ioctl_invoke_arg *arg,
1194 struct tee_param *param)
1195 {
1196 if (!ctx->teedev->desc->ops->invoke_func)
1197 return -EINVAL;
1198 return ctx->teedev->desc->ops->invoke_func(ctx, arg, param);
1199 }
1200 EXPORT_SYMBOL_GPL(tee_client_invoke_func);
1201
tee_client_cancel_req(struct tee_context * ctx,struct tee_ioctl_cancel_arg * arg)1202 int tee_client_cancel_req(struct tee_context *ctx,
1203 struct tee_ioctl_cancel_arg *arg)
1204 {
1205 if (!ctx->teedev->desc->ops->cancel_req)
1206 return -EINVAL;
1207 return ctx->teedev->desc->ops->cancel_req(ctx, arg->cancel_id,
1208 arg->session);
1209 }
1210
tee_client_device_match(struct device * dev,const struct device_driver * drv)1211 static int tee_client_device_match(struct device *dev,
1212 const struct device_driver *drv)
1213 {
1214 const struct tee_client_device_id *id_table;
1215 struct tee_client_device *tee_device;
1216
1217 id_table = to_tee_client_driver(drv)->id_table;
1218 tee_device = to_tee_client_device(dev);
1219
1220 while (!uuid_is_null(&id_table->uuid)) {
1221 if (uuid_equal(&tee_device->id.uuid, &id_table->uuid))
1222 return 1;
1223 id_table++;
1224 }
1225
1226 return 0;
1227 }
1228
tee_client_device_uevent(const struct device * dev,struct kobj_uevent_env * env)1229 static int tee_client_device_uevent(const struct device *dev,
1230 struct kobj_uevent_env *env)
1231 {
1232 uuid_t *dev_id = &to_tee_client_device(dev)->id.uuid;
1233
1234 return add_uevent_var(env, "MODALIAS=tee:%pUb", dev_id);
1235 }
1236
1237 const struct bus_type tee_bus_type = {
1238 .name = "tee",
1239 .match = tee_client_device_match,
1240 .uevent = tee_client_device_uevent,
1241 };
1242 EXPORT_SYMBOL_GPL(tee_bus_type);
1243
tee_init(void)1244 static int __init tee_init(void)
1245 {
1246 int rc;
1247
1248 rc = class_register(&tee_class);
1249 if (rc) {
1250 pr_err("couldn't create class\n");
1251 return rc;
1252 }
1253
1254 rc = alloc_chrdev_region(&tee_devt, 0, TEE_NUM_DEVICES, "tee");
1255 if (rc) {
1256 pr_err("failed to allocate char dev region\n");
1257 goto out_unreg_class;
1258 }
1259
1260 rc = bus_register(&tee_bus_type);
1261 if (rc) {
1262 pr_err("failed to register tee bus\n");
1263 goto out_unreg_chrdev;
1264 }
1265
1266 return 0;
1267
1268 out_unreg_chrdev:
1269 unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1270 out_unreg_class:
1271 class_unregister(&tee_class);
1272
1273 return rc;
1274 }
1275
tee_exit(void)1276 static void __exit tee_exit(void)
1277 {
1278 bus_unregister(&tee_bus_type);
1279 unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1280 class_unregister(&tee_class);
1281 }
1282
1283 subsys_initcall(tee_init);
1284 module_exit(tee_exit);
1285
1286 MODULE_AUTHOR("Linaro");
1287 MODULE_DESCRIPTION("TEE Driver");
1288 MODULE_VERSION("1.0");
1289 MODULE_LICENSE("GPL v2");
1290