xref: /linux/drivers/tee/tee_core.c (revision 63307d015b91e626c97bb82e88054af3d0b74643)
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/fs.h>
10 #include <linux/idr.h>
11 #include <linux/module.h>
12 #include <linux/slab.h>
13 #include <linux/tee_drv.h>
14 #include <linux/uaccess.h>
15 #include "tee_private.h"
16 
17 #define TEE_NUM_DEVICES	32
18 
19 #define TEE_IOCTL_PARAM_SIZE(x) (sizeof(struct tee_param) * (x))
20 
21 /*
22  * Unprivileged devices in the lower half range and privileged devices in
23  * the upper half range.
24  */
25 static DECLARE_BITMAP(dev_mask, TEE_NUM_DEVICES);
26 static DEFINE_SPINLOCK(driver_lock);
27 
28 static struct class *tee_class;
29 static dev_t tee_devt;
30 
31 static struct tee_context *teedev_open(struct tee_device *teedev)
32 {
33 	int rc;
34 	struct tee_context *ctx;
35 
36 	if (!tee_device_get(teedev))
37 		return ERR_PTR(-EINVAL);
38 
39 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
40 	if (!ctx) {
41 		rc = -ENOMEM;
42 		goto err;
43 	}
44 
45 	kref_init(&ctx->refcount);
46 	ctx->teedev = teedev;
47 	INIT_LIST_HEAD(&ctx->list_shm);
48 	rc = teedev->desc->ops->open(ctx);
49 	if (rc)
50 		goto err;
51 
52 	return ctx;
53 err:
54 	kfree(ctx);
55 	tee_device_put(teedev);
56 	return ERR_PTR(rc);
57 
58 }
59 
60 void teedev_ctx_get(struct tee_context *ctx)
61 {
62 	if (ctx->releasing)
63 		return;
64 
65 	kref_get(&ctx->refcount);
66 }
67 
68 static void teedev_ctx_release(struct kref *ref)
69 {
70 	struct tee_context *ctx = container_of(ref, struct tee_context,
71 					       refcount);
72 	ctx->releasing = true;
73 	ctx->teedev->desc->ops->release(ctx);
74 	kfree(ctx);
75 }
76 
77 void teedev_ctx_put(struct tee_context *ctx)
78 {
79 	if (ctx->releasing)
80 		return;
81 
82 	kref_put(&ctx->refcount, teedev_ctx_release);
83 }
84 
85 static void teedev_close_context(struct tee_context *ctx)
86 {
87 	tee_device_put(ctx->teedev);
88 	teedev_ctx_put(ctx);
89 }
90 
91 static int tee_open(struct inode *inode, struct file *filp)
92 {
93 	struct tee_context *ctx;
94 
95 	ctx = teedev_open(container_of(inode->i_cdev, struct tee_device, cdev));
96 	if (IS_ERR(ctx))
97 		return PTR_ERR(ctx);
98 
99 	/*
100 	 * Default user-space behaviour is to wait for tee-supplicant
101 	 * if not present for any requests in this context.
102 	 */
103 	ctx->supp_nowait = false;
104 	filp->private_data = ctx;
105 	return 0;
106 }
107 
108 static int tee_release(struct inode *inode, struct file *filp)
109 {
110 	teedev_close_context(filp->private_data);
111 	return 0;
112 }
113 
114 static int tee_ioctl_version(struct tee_context *ctx,
115 			     struct tee_ioctl_version_data __user *uvers)
116 {
117 	struct tee_ioctl_version_data vers;
118 
119 	ctx->teedev->desc->ops->get_version(ctx->teedev, &vers);
120 
121 	if (ctx->teedev->desc->flags & TEE_DESC_PRIVILEGED)
122 		vers.gen_caps |= TEE_GEN_CAP_PRIVILEGED;
123 
124 	if (copy_to_user(uvers, &vers, sizeof(vers)))
125 		return -EFAULT;
126 
127 	return 0;
128 }
129 
130 static int tee_ioctl_shm_alloc(struct tee_context *ctx,
131 			       struct tee_ioctl_shm_alloc_data __user *udata)
132 {
133 	long ret;
134 	struct tee_ioctl_shm_alloc_data data;
135 	struct tee_shm *shm;
136 
137 	if (copy_from_user(&data, udata, sizeof(data)))
138 		return -EFAULT;
139 
140 	/* Currently no input flags are supported */
141 	if (data.flags)
142 		return -EINVAL;
143 
144 	shm = tee_shm_alloc(ctx, data.size, TEE_SHM_MAPPED | TEE_SHM_DMA_BUF);
145 	if (IS_ERR(shm))
146 		return PTR_ERR(shm);
147 
148 	data.id = shm->id;
149 	data.flags = shm->flags;
150 	data.size = shm->size;
151 
152 	if (copy_to_user(udata, &data, sizeof(data)))
153 		ret = -EFAULT;
154 	else
155 		ret = tee_shm_get_fd(shm);
156 
157 	/*
158 	 * When user space closes the file descriptor the shared memory
159 	 * should be freed or if tee_shm_get_fd() failed then it will
160 	 * be freed immediately.
161 	 */
162 	tee_shm_put(shm);
163 	return ret;
164 }
165 
166 static int
167 tee_ioctl_shm_register(struct tee_context *ctx,
168 		       struct tee_ioctl_shm_register_data __user *udata)
169 {
170 	long ret;
171 	struct tee_ioctl_shm_register_data data;
172 	struct tee_shm *shm;
173 
174 	if (copy_from_user(&data, udata, sizeof(data)))
175 		return -EFAULT;
176 
177 	/* Currently no input flags are supported */
178 	if (data.flags)
179 		return -EINVAL;
180 
181 	shm = tee_shm_register(ctx, data.addr, data.length,
182 			       TEE_SHM_DMA_BUF | TEE_SHM_USER_MAPPED);
183 	if (IS_ERR(shm))
184 		return PTR_ERR(shm);
185 
186 	data.id = shm->id;
187 	data.flags = shm->flags;
188 	data.length = shm->size;
189 
190 	if (copy_to_user(udata, &data, sizeof(data)))
191 		ret = -EFAULT;
192 	else
193 		ret = tee_shm_get_fd(shm);
194 	/*
195 	 * When user space closes the file descriptor the shared memory
196 	 * should be freed or if tee_shm_get_fd() failed then it will
197 	 * be freed immediately.
198 	 */
199 	tee_shm_put(shm);
200 	return ret;
201 }
202 
203 static int params_from_user(struct tee_context *ctx, struct tee_param *params,
204 			    size_t num_params,
205 			    struct tee_ioctl_param __user *uparams)
206 {
207 	size_t n;
208 
209 	for (n = 0; n < num_params; n++) {
210 		struct tee_shm *shm;
211 		struct tee_ioctl_param ip;
212 
213 		if (copy_from_user(&ip, uparams + n, sizeof(ip)))
214 			return -EFAULT;
215 
216 		/* All unused attribute bits has to be zero */
217 		if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
218 			return -EINVAL;
219 
220 		params[n].attr = ip.attr;
221 		switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
222 		case TEE_IOCTL_PARAM_ATTR_TYPE_NONE:
223 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
224 			break;
225 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
226 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
227 			params[n].u.value.a = ip.a;
228 			params[n].u.value.b = ip.b;
229 			params[n].u.value.c = ip.c;
230 			break;
231 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
232 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
233 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
234 			/*
235 			 * If we fail to get a pointer to a shared memory
236 			 * object (and increase the ref count) from an
237 			 * identifier we return an error. All pointers that
238 			 * has been added in params have an increased ref
239 			 * count. It's the callers responibility to do
240 			 * tee_shm_put() on all resolved pointers.
241 			 */
242 			shm = tee_shm_get_from_id(ctx, ip.c);
243 			if (IS_ERR(shm))
244 				return PTR_ERR(shm);
245 
246 			/*
247 			 * Ensure offset + size does not overflow offset
248 			 * and does not overflow the size of the referred
249 			 * shared memory object.
250 			 */
251 			if ((ip.a + ip.b) < ip.a ||
252 			    (ip.a + ip.b) > shm->size) {
253 				tee_shm_put(shm);
254 				return -EINVAL;
255 			}
256 
257 			params[n].u.memref.shm_offs = ip.a;
258 			params[n].u.memref.size = ip.b;
259 			params[n].u.memref.shm = shm;
260 			break;
261 		default:
262 			/* Unknown attribute */
263 			return -EINVAL;
264 		}
265 	}
266 	return 0;
267 }
268 
269 static int params_to_user(struct tee_ioctl_param __user *uparams,
270 			  size_t num_params, struct tee_param *params)
271 {
272 	size_t n;
273 
274 	for (n = 0; n < num_params; n++) {
275 		struct tee_ioctl_param __user *up = uparams + n;
276 		struct tee_param *p = params + n;
277 
278 		switch (p->attr) {
279 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
280 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
281 			if (put_user(p->u.value.a, &up->a) ||
282 			    put_user(p->u.value.b, &up->b) ||
283 			    put_user(p->u.value.c, &up->c))
284 				return -EFAULT;
285 			break;
286 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
287 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
288 			if (put_user((u64)p->u.memref.size, &up->b))
289 				return -EFAULT;
290 		default:
291 			break;
292 		}
293 	}
294 	return 0;
295 }
296 
297 static int tee_ioctl_open_session(struct tee_context *ctx,
298 				  struct tee_ioctl_buf_data __user *ubuf)
299 {
300 	int rc;
301 	size_t n;
302 	struct tee_ioctl_buf_data buf;
303 	struct tee_ioctl_open_session_arg __user *uarg;
304 	struct tee_ioctl_open_session_arg arg;
305 	struct tee_ioctl_param __user *uparams = NULL;
306 	struct tee_param *params = NULL;
307 	bool have_session = false;
308 
309 	if (!ctx->teedev->desc->ops->open_session)
310 		return -EINVAL;
311 
312 	if (copy_from_user(&buf, ubuf, sizeof(buf)))
313 		return -EFAULT;
314 
315 	if (buf.buf_len > TEE_MAX_ARG_SIZE ||
316 	    buf.buf_len < sizeof(struct tee_ioctl_open_session_arg))
317 		return -EINVAL;
318 
319 	uarg = u64_to_user_ptr(buf.buf_ptr);
320 	if (copy_from_user(&arg, uarg, sizeof(arg)))
321 		return -EFAULT;
322 
323 	if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
324 		return -EINVAL;
325 
326 	if (arg.num_params) {
327 		params = kcalloc(arg.num_params, sizeof(struct tee_param),
328 				 GFP_KERNEL);
329 		if (!params)
330 			return -ENOMEM;
331 		uparams = uarg->params;
332 		rc = params_from_user(ctx, params, arg.num_params, uparams);
333 		if (rc)
334 			goto out;
335 	}
336 
337 	rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params);
338 	if (rc)
339 		goto out;
340 	have_session = true;
341 
342 	if (put_user(arg.session, &uarg->session) ||
343 	    put_user(arg.ret, &uarg->ret) ||
344 	    put_user(arg.ret_origin, &uarg->ret_origin)) {
345 		rc = -EFAULT;
346 		goto out;
347 	}
348 	rc = params_to_user(uparams, arg.num_params, params);
349 out:
350 	/*
351 	 * If we've succeeded to open the session but failed to communicate
352 	 * it back to user space, close the session again to avoid leakage.
353 	 */
354 	if (rc && have_session && ctx->teedev->desc->ops->close_session)
355 		ctx->teedev->desc->ops->close_session(ctx, arg.session);
356 
357 	if (params) {
358 		/* Decrease ref count for all valid shared memory pointers */
359 		for (n = 0; n < arg.num_params; n++)
360 			if (tee_param_is_memref(params + n) &&
361 			    params[n].u.memref.shm)
362 				tee_shm_put(params[n].u.memref.shm);
363 		kfree(params);
364 	}
365 
366 	return rc;
367 }
368 
369 static int tee_ioctl_invoke(struct tee_context *ctx,
370 			    struct tee_ioctl_buf_data __user *ubuf)
371 {
372 	int rc;
373 	size_t n;
374 	struct tee_ioctl_buf_data buf;
375 	struct tee_ioctl_invoke_arg __user *uarg;
376 	struct tee_ioctl_invoke_arg arg;
377 	struct tee_ioctl_param __user *uparams = NULL;
378 	struct tee_param *params = NULL;
379 
380 	if (!ctx->teedev->desc->ops->invoke_func)
381 		return -EINVAL;
382 
383 	if (copy_from_user(&buf, ubuf, sizeof(buf)))
384 		return -EFAULT;
385 
386 	if (buf.buf_len > TEE_MAX_ARG_SIZE ||
387 	    buf.buf_len < sizeof(struct tee_ioctl_invoke_arg))
388 		return -EINVAL;
389 
390 	uarg = u64_to_user_ptr(buf.buf_ptr);
391 	if (copy_from_user(&arg, uarg, sizeof(arg)))
392 		return -EFAULT;
393 
394 	if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
395 		return -EINVAL;
396 
397 	if (arg.num_params) {
398 		params = kcalloc(arg.num_params, sizeof(struct tee_param),
399 				 GFP_KERNEL);
400 		if (!params)
401 			return -ENOMEM;
402 		uparams = uarg->params;
403 		rc = params_from_user(ctx, params, arg.num_params, uparams);
404 		if (rc)
405 			goto out;
406 	}
407 
408 	rc = ctx->teedev->desc->ops->invoke_func(ctx, &arg, params);
409 	if (rc)
410 		goto out;
411 
412 	if (put_user(arg.ret, &uarg->ret) ||
413 	    put_user(arg.ret_origin, &uarg->ret_origin)) {
414 		rc = -EFAULT;
415 		goto out;
416 	}
417 	rc = params_to_user(uparams, arg.num_params, params);
418 out:
419 	if (params) {
420 		/* Decrease ref count for all valid shared memory pointers */
421 		for (n = 0; n < arg.num_params; n++)
422 			if (tee_param_is_memref(params + n) &&
423 			    params[n].u.memref.shm)
424 				tee_shm_put(params[n].u.memref.shm);
425 		kfree(params);
426 	}
427 	return rc;
428 }
429 
430 static int tee_ioctl_cancel(struct tee_context *ctx,
431 			    struct tee_ioctl_cancel_arg __user *uarg)
432 {
433 	struct tee_ioctl_cancel_arg arg;
434 
435 	if (!ctx->teedev->desc->ops->cancel_req)
436 		return -EINVAL;
437 
438 	if (copy_from_user(&arg, uarg, sizeof(arg)))
439 		return -EFAULT;
440 
441 	return ctx->teedev->desc->ops->cancel_req(ctx, arg.cancel_id,
442 						  arg.session);
443 }
444 
445 static int
446 tee_ioctl_close_session(struct tee_context *ctx,
447 			struct tee_ioctl_close_session_arg __user *uarg)
448 {
449 	struct tee_ioctl_close_session_arg arg;
450 
451 	if (!ctx->teedev->desc->ops->close_session)
452 		return -EINVAL;
453 
454 	if (copy_from_user(&arg, uarg, sizeof(arg)))
455 		return -EFAULT;
456 
457 	return ctx->teedev->desc->ops->close_session(ctx, arg.session);
458 }
459 
460 static int params_to_supp(struct tee_context *ctx,
461 			  struct tee_ioctl_param __user *uparams,
462 			  size_t num_params, struct tee_param *params)
463 {
464 	size_t n;
465 
466 	for (n = 0; n < num_params; n++) {
467 		struct tee_ioctl_param ip;
468 		struct tee_param *p = params + n;
469 
470 		ip.attr = p->attr;
471 		switch (p->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
472 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
473 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
474 			ip.a = p->u.value.a;
475 			ip.b = p->u.value.b;
476 			ip.c = p->u.value.c;
477 			break;
478 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
479 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
480 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
481 			ip.b = p->u.memref.size;
482 			if (!p->u.memref.shm) {
483 				ip.a = 0;
484 				ip.c = (u64)-1; /* invalid shm id */
485 				break;
486 			}
487 			ip.a = p->u.memref.shm_offs;
488 			ip.c = p->u.memref.shm->id;
489 			break;
490 		default:
491 			ip.a = 0;
492 			ip.b = 0;
493 			ip.c = 0;
494 			break;
495 		}
496 
497 		if (copy_to_user(uparams + n, &ip, sizeof(ip)))
498 			return -EFAULT;
499 	}
500 
501 	return 0;
502 }
503 
504 static int tee_ioctl_supp_recv(struct tee_context *ctx,
505 			       struct tee_ioctl_buf_data __user *ubuf)
506 {
507 	int rc;
508 	struct tee_ioctl_buf_data buf;
509 	struct tee_iocl_supp_recv_arg __user *uarg;
510 	struct tee_param *params;
511 	u32 num_params;
512 	u32 func;
513 
514 	if (!ctx->teedev->desc->ops->supp_recv)
515 		return -EINVAL;
516 
517 	if (copy_from_user(&buf, ubuf, sizeof(buf)))
518 		return -EFAULT;
519 
520 	if (buf.buf_len > TEE_MAX_ARG_SIZE ||
521 	    buf.buf_len < sizeof(struct tee_iocl_supp_recv_arg))
522 		return -EINVAL;
523 
524 	uarg = u64_to_user_ptr(buf.buf_ptr);
525 	if (get_user(num_params, &uarg->num_params))
526 		return -EFAULT;
527 
528 	if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) != buf.buf_len)
529 		return -EINVAL;
530 
531 	params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
532 	if (!params)
533 		return -ENOMEM;
534 
535 	rc = params_from_user(ctx, params, num_params, uarg->params);
536 	if (rc)
537 		goto out;
538 
539 	rc = ctx->teedev->desc->ops->supp_recv(ctx, &func, &num_params, params);
540 	if (rc)
541 		goto out;
542 
543 	if (put_user(func, &uarg->func) ||
544 	    put_user(num_params, &uarg->num_params)) {
545 		rc = -EFAULT;
546 		goto out;
547 	}
548 
549 	rc = params_to_supp(ctx, uarg->params, num_params, params);
550 out:
551 	kfree(params);
552 	return rc;
553 }
554 
555 static int params_from_supp(struct tee_param *params, size_t num_params,
556 			    struct tee_ioctl_param __user *uparams)
557 {
558 	size_t n;
559 
560 	for (n = 0; n < num_params; n++) {
561 		struct tee_param *p = params + n;
562 		struct tee_ioctl_param ip;
563 
564 		if (copy_from_user(&ip, uparams + n, sizeof(ip)))
565 			return -EFAULT;
566 
567 		/* All unused attribute bits has to be zero */
568 		if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
569 			return -EINVAL;
570 
571 		p->attr = ip.attr;
572 		switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
573 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
574 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
575 			/* Only out and in/out values can be updated */
576 			p->u.value.a = ip.a;
577 			p->u.value.b = ip.b;
578 			p->u.value.c = ip.c;
579 			break;
580 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
581 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
582 			/*
583 			 * Only the size of the memref can be updated.
584 			 * Since we don't have access to the original
585 			 * parameters here, only store the supplied size.
586 			 * The driver will copy the updated size into the
587 			 * original parameters.
588 			 */
589 			p->u.memref.shm = NULL;
590 			p->u.memref.shm_offs = 0;
591 			p->u.memref.size = ip.b;
592 			break;
593 		default:
594 			memset(&p->u, 0, sizeof(p->u));
595 			break;
596 		}
597 	}
598 	return 0;
599 }
600 
601 static int tee_ioctl_supp_send(struct tee_context *ctx,
602 			       struct tee_ioctl_buf_data __user *ubuf)
603 {
604 	long rc;
605 	struct tee_ioctl_buf_data buf;
606 	struct tee_iocl_supp_send_arg __user *uarg;
607 	struct tee_param *params;
608 	u32 num_params;
609 	u32 ret;
610 
611 	/* Not valid for this driver */
612 	if (!ctx->teedev->desc->ops->supp_send)
613 		return -EINVAL;
614 
615 	if (copy_from_user(&buf, ubuf, sizeof(buf)))
616 		return -EFAULT;
617 
618 	if (buf.buf_len > TEE_MAX_ARG_SIZE ||
619 	    buf.buf_len < sizeof(struct tee_iocl_supp_send_arg))
620 		return -EINVAL;
621 
622 	uarg = u64_to_user_ptr(buf.buf_ptr);
623 	if (get_user(ret, &uarg->ret) ||
624 	    get_user(num_params, &uarg->num_params))
625 		return -EFAULT;
626 
627 	if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) > buf.buf_len)
628 		return -EINVAL;
629 
630 	params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
631 	if (!params)
632 		return -ENOMEM;
633 
634 	rc = params_from_supp(params, num_params, uarg->params);
635 	if (rc)
636 		goto out;
637 
638 	rc = ctx->teedev->desc->ops->supp_send(ctx, ret, num_params, params);
639 out:
640 	kfree(params);
641 	return rc;
642 }
643 
644 static long tee_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
645 {
646 	struct tee_context *ctx = filp->private_data;
647 	void __user *uarg = (void __user *)arg;
648 
649 	switch (cmd) {
650 	case TEE_IOC_VERSION:
651 		return tee_ioctl_version(ctx, uarg);
652 	case TEE_IOC_SHM_ALLOC:
653 		return tee_ioctl_shm_alloc(ctx, uarg);
654 	case TEE_IOC_SHM_REGISTER:
655 		return tee_ioctl_shm_register(ctx, uarg);
656 	case TEE_IOC_OPEN_SESSION:
657 		return tee_ioctl_open_session(ctx, uarg);
658 	case TEE_IOC_INVOKE:
659 		return tee_ioctl_invoke(ctx, uarg);
660 	case TEE_IOC_CANCEL:
661 		return tee_ioctl_cancel(ctx, uarg);
662 	case TEE_IOC_CLOSE_SESSION:
663 		return tee_ioctl_close_session(ctx, uarg);
664 	case TEE_IOC_SUPPL_RECV:
665 		return tee_ioctl_supp_recv(ctx, uarg);
666 	case TEE_IOC_SUPPL_SEND:
667 		return tee_ioctl_supp_send(ctx, uarg);
668 	default:
669 		return -EINVAL;
670 	}
671 }
672 
673 static const struct file_operations tee_fops = {
674 	.owner = THIS_MODULE,
675 	.open = tee_open,
676 	.release = tee_release,
677 	.unlocked_ioctl = tee_ioctl,
678 	.compat_ioctl = tee_ioctl,
679 };
680 
681 static void tee_release_device(struct device *dev)
682 {
683 	struct tee_device *teedev = container_of(dev, struct tee_device, dev);
684 
685 	spin_lock(&driver_lock);
686 	clear_bit(teedev->id, dev_mask);
687 	spin_unlock(&driver_lock);
688 	mutex_destroy(&teedev->mutex);
689 	idr_destroy(&teedev->idr);
690 	kfree(teedev);
691 }
692 
693 /**
694  * tee_device_alloc() - Allocate a new struct tee_device instance
695  * @teedesc:	Descriptor for this driver
696  * @dev:	Parent device for this device
697  * @pool:	Shared memory pool, NULL if not used
698  * @driver_data: Private driver data for this device
699  *
700  * Allocates a new struct tee_device instance. The device is
701  * removed by tee_device_unregister().
702  *
703  * @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
704  */
705 struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
706 				    struct device *dev,
707 				    struct tee_shm_pool *pool,
708 				    void *driver_data)
709 {
710 	struct tee_device *teedev;
711 	void *ret;
712 	int rc, max_id;
713 	int offs = 0;
714 
715 	if (!teedesc || !teedesc->name || !teedesc->ops ||
716 	    !teedesc->ops->get_version || !teedesc->ops->open ||
717 	    !teedesc->ops->release || !pool)
718 		return ERR_PTR(-EINVAL);
719 
720 	teedev = kzalloc(sizeof(*teedev), GFP_KERNEL);
721 	if (!teedev) {
722 		ret = ERR_PTR(-ENOMEM);
723 		goto err;
724 	}
725 
726 	max_id = TEE_NUM_DEVICES / 2;
727 
728 	if (teedesc->flags & TEE_DESC_PRIVILEGED) {
729 		offs = TEE_NUM_DEVICES / 2;
730 		max_id = TEE_NUM_DEVICES;
731 	}
732 
733 	spin_lock(&driver_lock);
734 	teedev->id = find_next_zero_bit(dev_mask, max_id, offs);
735 	if (teedev->id < max_id)
736 		set_bit(teedev->id, dev_mask);
737 	spin_unlock(&driver_lock);
738 
739 	if (teedev->id >= max_id) {
740 		ret = ERR_PTR(-ENOMEM);
741 		goto err;
742 	}
743 
744 	snprintf(teedev->name, sizeof(teedev->name), "tee%s%d",
745 		 teedesc->flags & TEE_DESC_PRIVILEGED ? "priv" : "",
746 		 teedev->id - offs);
747 
748 	teedev->dev.class = tee_class;
749 	teedev->dev.release = tee_release_device;
750 	teedev->dev.parent = dev;
751 
752 	teedev->dev.devt = MKDEV(MAJOR(tee_devt), teedev->id);
753 
754 	rc = dev_set_name(&teedev->dev, "%s", teedev->name);
755 	if (rc) {
756 		ret = ERR_PTR(rc);
757 		goto err_devt;
758 	}
759 
760 	cdev_init(&teedev->cdev, &tee_fops);
761 	teedev->cdev.owner = teedesc->owner;
762 	teedev->cdev.kobj.parent = &teedev->dev.kobj;
763 
764 	dev_set_drvdata(&teedev->dev, driver_data);
765 	device_initialize(&teedev->dev);
766 
767 	/* 1 as tee_device_unregister() does one final tee_device_put() */
768 	teedev->num_users = 1;
769 	init_completion(&teedev->c_no_users);
770 	mutex_init(&teedev->mutex);
771 	idr_init(&teedev->idr);
772 
773 	teedev->desc = teedesc;
774 	teedev->pool = pool;
775 
776 	return teedev;
777 err_devt:
778 	unregister_chrdev_region(teedev->dev.devt, 1);
779 err:
780 	pr_err("could not register %s driver\n",
781 	       teedesc->flags & TEE_DESC_PRIVILEGED ? "privileged" : "client");
782 	if (teedev && teedev->id < TEE_NUM_DEVICES) {
783 		spin_lock(&driver_lock);
784 		clear_bit(teedev->id, dev_mask);
785 		spin_unlock(&driver_lock);
786 	}
787 	kfree(teedev);
788 	return ret;
789 }
790 EXPORT_SYMBOL_GPL(tee_device_alloc);
791 
792 static ssize_t implementation_id_show(struct device *dev,
793 				      struct device_attribute *attr, char *buf)
794 {
795 	struct tee_device *teedev = container_of(dev, struct tee_device, dev);
796 	struct tee_ioctl_version_data vers;
797 
798 	teedev->desc->ops->get_version(teedev, &vers);
799 	return scnprintf(buf, PAGE_SIZE, "%d\n", vers.impl_id);
800 }
801 static DEVICE_ATTR_RO(implementation_id);
802 
803 static struct attribute *tee_dev_attrs[] = {
804 	&dev_attr_implementation_id.attr,
805 	NULL
806 };
807 
808 static const struct attribute_group tee_dev_group = {
809 	.attrs = tee_dev_attrs,
810 };
811 
812 /**
813  * tee_device_register() - Registers a TEE device
814  * @teedev:	Device to register
815  *
816  * tee_device_unregister() need to be called to remove the @teedev if
817  * this function fails.
818  *
819  * @returns < 0 on failure
820  */
821 int tee_device_register(struct tee_device *teedev)
822 {
823 	int rc;
824 
825 	if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
826 		dev_err(&teedev->dev, "attempt to register twice\n");
827 		return -EINVAL;
828 	}
829 
830 	rc = cdev_add(&teedev->cdev, teedev->dev.devt, 1);
831 	if (rc) {
832 		dev_err(&teedev->dev,
833 			"unable to cdev_add() %s, major %d, minor %d, err=%d\n",
834 			teedev->name, MAJOR(teedev->dev.devt),
835 			MINOR(teedev->dev.devt), rc);
836 		return rc;
837 	}
838 
839 	rc = device_add(&teedev->dev);
840 	if (rc) {
841 		dev_err(&teedev->dev,
842 			"unable to device_add() %s, major %d, minor %d, err=%d\n",
843 			teedev->name, MAJOR(teedev->dev.devt),
844 			MINOR(teedev->dev.devt), rc);
845 		goto err_device_add;
846 	}
847 
848 	rc = sysfs_create_group(&teedev->dev.kobj, &tee_dev_group);
849 	if (rc) {
850 		dev_err(&teedev->dev,
851 			"failed to create sysfs attributes, err=%d\n", rc);
852 		goto err_sysfs_create_group;
853 	}
854 
855 	teedev->flags |= TEE_DEVICE_FLAG_REGISTERED;
856 	return 0;
857 
858 err_sysfs_create_group:
859 	device_del(&teedev->dev);
860 err_device_add:
861 	cdev_del(&teedev->cdev);
862 	return rc;
863 }
864 EXPORT_SYMBOL_GPL(tee_device_register);
865 
866 void tee_device_put(struct tee_device *teedev)
867 {
868 	mutex_lock(&teedev->mutex);
869 	/* Shouldn't put in this state */
870 	if (!WARN_ON(!teedev->desc)) {
871 		teedev->num_users--;
872 		if (!teedev->num_users) {
873 			teedev->desc = NULL;
874 			complete(&teedev->c_no_users);
875 		}
876 	}
877 	mutex_unlock(&teedev->mutex);
878 }
879 
880 bool tee_device_get(struct tee_device *teedev)
881 {
882 	mutex_lock(&teedev->mutex);
883 	if (!teedev->desc) {
884 		mutex_unlock(&teedev->mutex);
885 		return false;
886 	}
887 	teedev->num_users++;
888 	mutex_unlock(&teedev->mutex);
889 	return true;
890 }
891 
892 /**
893  * tee_device_unregister() - Removes a TEE device
894  * @teedev:	Device to unregister
895  *
896  * This function should be called to remove the @teedev even if
897  * tee_device_register() hasn't been called yet. Does nothing if
898  * @teedev is NULL.
899  */
900 void tee_device_unregister(struct tee_device *teedev)
901 {
902 	if (!teedev)
903 		return;
904 
905 	if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
906 		sysfs_remove_group(&teedev->dev.kobj, &tee_dev_group);
907 		cdev_del(&teedev->cdev);
908 		device_del(&teedev->dev);
909 	}
910 
911 	tee_device_put(teedev);
912 	wait_for_completion(&teedev->c_no_users);
913 
914 	/*
915 	 * No need to take a mutex any longer now since teedev->desc was
916 	 * set to NULL before teedev->c_no_users was completed.
917 	 */
918 
919 	teedev->pool = NULL;
920 
921 	put_device(&teedev->dev);
922 }
923 EXPORT_SYMBOL_GPL(tee_device_unregister);
924 
925 /**
926  * tee_get_drvdata() - Return driver_data pointer
927  * @teedev:	Device containing the driver_data pointer
928  * @returns the driver_data pointer supplied to tee_register().
929  */
930 void *tee_get_drvdata(struct tee_device *teedev)
931 {
932 	return dev_get_drvdata(&teedev->dev);
933 }
934 EXPORT_SYMBOL_GPL(tee_get_drvdata);
935 
936 struct match_dev_data {
937 	struct tee_ioctl_version_data *vers;
938 	const void *data;
939 	int (*match)(struct tee_ioctl_version_data *, const void *);
940 };
941 
942 static int match_dev(struct device *dev, const void *data)
943 {
944 	const struct match_dev_data *match_data = data;
945 	struct tee_device *teedev = container_of(dev, struct tee_device, dev);
946 
947 	teedev->desc->ops->get_version(teedev, match_data->vers);
948 	return match_data->match(match_data->vers, match_data->data);
949 }
950 
951 struct tee_context *
952 tee_client_open_context(struct tee_context *start,
953 			int (*match)(struct tee_ioctl_version_data *,
954 				     const void *),
955 			const void *data, struct tee_ioctl_version_data *vers)
956 {
957 	struct device *dev = NULL;
958 	struct device *put_dev = NULL;
959 	struct tee_context *ctx = NULL;
960 	struct tee_ioctl_version_data v;
961 	struct match_dev_data match_data = { vers ? vers : &v, data, match };
962 
963 	if (start)
964 		dev = &start->teedev->dev;
965 
966 	do {
967 		dev = class_find_device(tee_class, dev, &match_data, match_dev);
968 		if (!dev) {
969 			ctx = ERR_PTR(-ENOENT);
970 			break;
971 		}
972 
973 		put_device(put_dev);
974 		put_dev = dev;
975 
976 		ctx = teedev_open(container_of(dev, struct tee_device, dev));
977 	} while (IS_ERR(ctx) && PTR_ERR(ctx) != -ENOMEM);
978 
979 	put_device(put_dev);
980 	/*
981 	 * Default behaviour for in kernel client is to not wait for
982 	 * tee-supplicant if not present for any requests in this context.
983 	 * Also this flag could be configured again before call to
984 	 * tee_client_open_session() if any in kernel client requires
985 	 * different behaviour.
986 	 */
987 	if (!IS_ERR(ctx))
988 		ctx->supp_nowait = true;
989 
990 	return ctx;
991 }
992 EXPORT_SYMBOL_GPL(tee_client_open_context);
993 
994 void tee_client_close_context(struct tee_context *ctx)
995 {
996 	teedev_close_context(ctx);
997 }
998 EXPORT_SYMBOL_GPL(tee_client_close_context);
999 
1000 void tee_client_get_version(struct tee_context *ctx,
1001 			    struct tee_ioctl_version_data *vers)
1002 {
1003 	ctx->teedev->desc->ops->get_version(ctx->teedev, vers);
1004 }
1005 EXPORT_SYMBOL_GPL(tee_client_get_version);
1006 
1007 int tee_client_open_session(struct tee_context *ctx,
1008 			    struct tee_ioctl_open_session_arg *arg,
1009 			    struct tee_param *param)
1010 {
1011 	if (!ctx->teedev->desc->ops->open_session)
1012 		return -EINVAL;
1013 	return ctx->teedev->desc->ops->open_session(ctx, arg, param);
1014 }
1015 EXPORT_SYMBOL_GPL(tee_client_open_session);
1016 
1017 int tee_client_close_session(struct tee_context *ctx, u32 session)
1018 {
1019 	if (!ctx->teedev->desc->ops->close_session)
1020 		return -EINVAL;
1021 	return ctx->teedev->desc->ops->close_session(ctx, session);
1022 }
1023 EXPORT_SYMBOL_GPL(tee_client_close_session);
1024 
1025 int tee_client_invoke_func(struct tee_context *ctx,
1026 			   struct tee_ioctl_invoke_arg *arg,
1027 			   struct tee_param *param)
1028 {
1029 	if (!ctx->teedev->desc->ops->invoke_func)
1030 		return -EINVAL;
1031 	return ctx->teedev->desc->ops->invoke_func(ctx, arg, param);
1032 }
1033 EXPORT_SYMBOL_GPL(tee_client_invoke_func);
1034 
1035 int tee_client_cancel_req(struct tee_context *ctx,
1036 			  struct tee_ioctl_cancel_arg *arg)
1037 {
1038 	if (!ctx->teedev->desc->ops->cancel_req)
1039 		return -EINVAL;
1040 	return ctx->teedev->desc->ops->cancel_req(ctx, arg->cancel_id,
1041 						  arg->session);
1042 }
1043 
1044 static int tee_client_device_match(struct device *dev,
1045 				   struct device_driver *drv)
1046 {
1047 	const struct tee_client_device_id *id_table;
1048 	struct tee_client_device *tee_device;
1049 
1050 	id_table = to_tee_client_driver(drv)->id_table;
1051 	tee_device = to_tee_client_device(dev);
1052 
1053 	while (!uuid_is_null(&id_table->uuid)) {
1054 		if (uuid_equal(&tee_device->id.uuid, &id_table->uuid))
1055 			return 1;
1056 		id_table++;
1057 	}
1058 
1059 	return 0;
1060 }
1061 
1062 static int tee_client_device_uevent(struct device *dev,
1063 				    struct kobj_uevent_env *env)
1064 {
1065 	uuid_t *dev_id = &to_tee_client_device(dev)->id.uuid;
1066 
1067 	return add_uevent_var(env, "MODALIAS=tee:%pUb", dev_id);
1068 }
1069 
1070 struct bus_type tee_bus_type = {
1071 	.name		= "tee",
1072 	.match		= tee_client_device_match,
1073 	.uevent		= tee_client_device_uevent,
1074 };
1075 EXPORT_SYMBOL_GPL(tee_bus_type);
1076 
1077 static int __init tee_init(void)
1078 {
1079 	int rc;
1080 
1081 	tee_class = class_create(THIS_MODULE, "tee");
1082 	if (IS_ERR(tee_class)) {
1083 		pr_err("couldn't create class\n");
1084 		return PTR_ERR(tee_class);
1085 	}
1086 
1087 	rc = alloc_chrdev_region(&tee_devt, 0, TEE_NUM_DEVICES, "tee");
1088 	if (rc) {
1089 		pr_err("failed to allocate char dev region\n");
1090 		goto out_unreg_class;
1091 	}
1092 
1093 	rc = bus_register(&tee_bus_type);
1094 	if (rc) {
1095 		pr_err("failed to register tee bus\n");
1096 		goto out_unreg_chrdev;
1097 	}
1098 
1099 	return 0;
1100 
1101 out_unreg_chrdev:
1102 	unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1103 out_unreg_class:
1104 	class_destroy(tee_class);
1105 	tee_class = NULL;
1106 
1107 	return rc;
1108 }
1109 
1110 static void __exit tee_exit(void)
1111 {
1112 	bus_unregister(&tee_bus_type);
1113 	unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1114 	class_destroy(tee_class);
1115 	tee_class = NULL;
1116 }
1117 
1118 subsys_initcall(tee_init);
1119 module_exit(tee_exit);
1120 
1121 MODULE_AUTHOR("Linaro");
1122 MODULE_DESCRIPTION("TEE Driver");
1123 MODULE_VERSION("1.0");
1124 MODULE_LICENSE("GPL v2");
1125