xref: /linux/drivers/tee/tee_core.c (revision 3f0a50f345f78183f6e9b39c2f45ca5dcaa511ca)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2015-2016, Linaro Limited
4  */
5 
6 #define pr_fmt(fmt) "%s: " fmt, __func__
7 
8 #include <linux/cdev.h>
9 #include <linux/cred.h>
10 #include <linux/fs.h>
11 #include <linux/idr.h>
12 #include <linux/module.h>
13 #include <linux/slab.h>
14 #include <linux/tee_drv.h>
15 #include <linux/uaccess.h>
16 #include <crypto/hash.h>
17 #include <crypto/sha1.h>
18 #include "tee_private.h"
19 
20 #define TEE_NUM_DEVICES	32
21 
22 #define TEE_IOCTL_PARAM_SIZE(x) (sizeof(struct tee_param) * (x))
23 
24 #define TEE_UUID_NS_NAME_SIZE	128
25 
26 /*
27  * TEE Client UUID name space identifier (UUIDv4)
28  *
29  * Value here is random UUID that is allocated as name space identifier for
30  * forming Client UUID's for TEE environment using UUIDv5 scheme.
31  */
32 static const uuid_t tee_client_uuid_ns = UUID_INIT(0x58ac9ca0, 0x2086, 0x4683,
33 						   0xa1, 0xb8, 0xec, 0x4b,
34 						   0xc0, 0x8e, 0x01, 0xb6);
35 
36 /*
37  * Unprivileged devices in the lower half range and privileged devices in
38  * the upper half range.
39  */
40 static DECLARE_BITMAP(dev_mask, TEE_NUM_DEVICES);
41 static DEFINE_SPINLOCK(driver_lock);
42 
43 static struct class *tee_class;
44 static dev_t tee_devt;
45 
46 struct tee_context *teedev_open(struct tee_device *teedev)
47 {
48 	int rc;
49 	struct tee_context *ctx;
50 
51 	if (!tee_device_get(teedev))
52 		return ERR_PTR(-EINVAL);
53 
54 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
55 	if (!ctx) {
56 		rc = -ENOMEM;
57 		goto err;
58 	}
59 
60 	kref_init(&ctx->refcount);
61 	ctx->teedev = teedev;
62 	rc = teedev->desc->ops->open(ctx);
63 	if (rc)
64 		goto err;
65 
66 	return ctx;
67 err:
68 	kfree(ctx);
69 	tee_device_put(teedev);
70 	return ERR_PTR(rc);
71 
72 }
73 EXPORT_SYMBOL_GPL(teedev_open);
74 
75 void teedev_ctx_get(struct tee_context *ctx)
76 {
77 	if (ctx->releasing)
78 		return;
79 
80 	kref_get(&ctx->refcount);
81 }
82 
83 static void teedev_ctx_release(struct kref *ref)
84 {
85 	struct tee_context *ctx = container_of(ref, struct tee_context,
86 					       refcount);
87 	ctx->releasing = true;
88 	ctx->teedev->desc->ops->release(ctx);
89 	kfree(ctx);
90 }
91 
92 void teedev_ctx_put(struct tee_context *ctx)
93 {
94 	if (ctx->releasing)
95 		return;
96 
97 	kref_put(&ctx->refcount, teedev_ctx_release);
98 }
99 
100 void teedev_close_context(struct tee_context *ctx)
101 {
102 	struct tee_device *teedev = ctx->teedev;
103 
104 	teedev_ctx_put(ctx);
105 	tee_device_put(teedev);
106 }
107 EXPORT_SYMBOL_GPL(teedev_close_context);
108 
109 static int tee_open(struct inode *inode, struct file *filp)
110 {
111 	struct tee_context *ctx;
112 
113 	ctx = teedev_open(container_of(inode->i_cdev, struct tee_device, cdev));
114 	if (IS_ERR(ctx))
115 		return PTR_ERR(ctx);
116 
117 	/*
118 	 * Default user-space behaviour is to wait for tee-supplicant
119 	 * if not present for any requests in this context.
120 	 */
121 	ctx->supp_nowait = false;
122 	filp->private_data = ctx;
123 	return 0;
124 }
125 
126 static int tee_release(struct inode *inode, struct file *filp)
127 {
128 	teedev_close_context(filp->private_data);
129 	return 0;
130 }
131 
132 /**
133  * uuid_v5() - Calculate UUIDv5
134  * @uuid: Resulting UUID
135  * @ns: Name space ID for UUIDv5 function
136  * @name: Name for UUIDv5 function
137  * @size: Size of name
138  *
139  * UUIDv5 is specific in RFC 4122.
140  *
141  * This implements section (for SHA-1):
142  * 4.3.  Algorithm for Creating a Name-Based UUID
143  */
144 static int uuid_v5(uuid_t *uuid, const uuid_t *ns, const void *name,
145 		   size_t size)
146 {
147 	unsigned char hash[SHA1_DIGEST_SIZE];
148 	struct crypto_shash *shash = NULL;
149 	struct shash_desc *desc = NULL;
150 	int rc;
151 
152 	shash = crypto_alloc_shash("sha1", 0, 0);
153 	if (IS_ERR(shash)) {
154 		rc = PTR_ERR(shash);
155 		pr_err("shash(sha1) allocation failed\n");
156 		return rc;
157 	}
158 
159 	desc = kzalloc(sizeof(*desc) + crypto_shash_descsize(shash),
160 		       GFP_KERNEL);
161 	if (!desc) {
162 		rc = -ENOMEM;
163 		goto out_free_shash;
164 	}
165 
166 	desc->tfm = shash;
167 
168 	rc = crypto_shash_init(desc);
169 	if (rc < 0)
170 		goto out_free_desc;
171 
172 	rc = crypto_shash_update(desc, (const u8 *)ns, sizeof(*ns));
173 	if (rc < 0)
174 		goto out_free_desc;
175 
176 	rc = crypto_shash_update(desc, (const u8 *)name, size);
177 	if (rc < 0)
178 		goto out_free_desc;
179 
180 	rc = crypto_shash_final(desc, hash);
181 	if (rc < 0)
182 		goto out_free_desc;
183 
184 	memcpy(uuid->b, hash, UUID_SIZE);
185 
186 	/* Tag for version 5 */
187 	uuid->b[6] = (hash[6] & 0x0F) | 0x50;
188 	uuid->b[8] = (hash[8] & 0x3F) | 0x80;
189 
190 out_free_desc:
191 	kfree(desc);
192 
193 out_free_shash:
194 	crypto_free_shash(shash);
195 	return rc;
196 }
197 
198 int tee_session_calc_client_uuid(uuid_t *uuid, u32 connection_method,
199 				 const u8 connection_data[TEE_IOCTL_UUID_LEN])
200 {
201 	gid_t ns_grp = (gid_t)-1;
202 	kgid_t grp = INVALID_GID;
203 	char *name = NULL;
204 	int name_len;
205 	int rc;
206 
207 	if (connection_method == TEE_IOCTL_LOGIN_PUBLIC ||
208 	    connection_method == TEE_IOCTL_LOGIN_REE_KERNEL) {
209 		/* Nil UUID to be passed to TEE environment */
210 		uuid_copy(uuid, &uuid_null);
211 		return 0;
212 	}
213 
214 	/*
215 	 * In Linux environment client UUID is based on UUIDv5.
216 	 *
217 	 * Determine client UUID with following semantics for 'name':
218 	 *
219 	 * For TEEC_LOGIN_USER:
220 	 * uid=<uid>
221 	 *
222 	 * For TEEC_LOGIN_GROUP:
223 	 * gid=<gid>
224 	 *
225 	 */
226 
227 	name = kzalloc(TEE_UUID_NS_NAME_SIZE, GFP_KERNEL);
228 	if (!name)
229 		return -ENOMEM;
230 
231 	switch (connection_method) {
232 	case TEE_IOCTL_LOGIN_USER:
233 		name_len = snprintf(name, TEE_UUID_NS_NAME_SIZE, "uid=%x",
234 				    current_euid().val);
235 		if (name_len >= TEE_UUID_NS_NAME_SIZE) {
236 			rc = -E2BIG;
237 			goto out_free_name;
238 		}
239 		break;
240 
241 	case TEE_IOCTL_LOGIN_GROUP:
242 		memcpy(&ns_grp, connection_data, sizeof(gid_t));
243 		grp = make_kgid(current_user_ns(), ns_grp);
244 		if (!gid_valid(grp) || !in_egroup_p(grp)) {
245 			rc = -EPERM;
246 			goto out_free_name;
247 		}
248 
249 		name_len = snprintf(name, TEE_UUID_NS_NAME_SIZE, "gid=%x",
250 				    grp.val);
251 		if (name_len >= TEE_UUID_NS_NAME_SIZE) {
252 			rc = -E2BIG;
253 			goto out_free_name;
254 		}
255 		break;
256 
257 	default:
258 		rc = -EINVAL;
259 		goto out_free_name;
260 	}
261 
262 	rc = uuid_v5(uuid, &tee_client_uuid_ns, name, name_len);
263 out_free_name:
264 	kfree(name);
265 
266 	return rc;
267 }
268 EXPORT_SYMBOL_GPL(tee_session_calc_client_uuid);
269 
270 static int tee_ioctl_version(struct tee_context *ctx,
271 			     struct tee_ioctl_version_data __user *uvers)
272 {
273 	struct tee_ioctl_version_data vers;
274 
275 	ctx->teedev->desc->ops->get_version(ctx->teedev, &vers);
276 
277 	if (ctx->teedev->desc->flags & TEE_DESC_PRIVILEGED)
278 		vers.gen_caps |= TEE_GEN_CAP_PRIVILEGED;
279 
280 	if (copy_to_user(uvers, &vers, sizeof(vers)))
281 		return -EFAULT;
282 
283 	return 0;
284 }
285 
286 static int tee_ioctl_shm_alloc(struct tee_context *ctx,
287 			       struct tee_ioctl_shm_alloc_data __user *udata)
288 {
289 	long ret;
290 	struct tee_ioctl_shm_alloc_data data;
291 	struct tee_shm *shm;
292 
293 	if (copy_from_user(&data, udata, sizeof(data)))
294 		return -EFAULT;
295 
296 	/* Currently no input flags are supported */
297 	if (data.flags)
298 		return -EINVAL;
299 
300 	shm = tee_shm_alloc_user_buf(ctx, data.size);
301 	if (IS_ERR(shm))
302 		return PTR_ERR(shm);
303 
304 	data.id = shm->id;
305 	data.flags = shm->flags;
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
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.flags = shm->flags;
343 	data.length = shm->size;
344 
345 	if (copy_to_user(udata, &data, sizeof(data)))
346 		ret = -EFAULT;
347 	else
348 		ret = tee_shm_get_fd(shm);
349 	/*
350 	 * When user space closes the file descriptor the shared memory
351 	 * should be freed or if tee_shm_get_fd() failed then it will
352 	 * be freed immediately.
353 	 */
354 	tee_shm_put(shm);
355 	return ret;
356 }
357 
358 static int params_from_user(struct tee_context *ctx, struct tee_param *params,
359 			    size_t num_params,
360 			    struct tee_ioctl_param __user *uparams)
361 {
362 	size_t n;
363 
364 	for (n = 0; n < num_params; n++) {
365 		struct tee_shm *shm;
366 		struct tee_ioctl_param ip;
367 
368 		if (copy_from_user(&ip, uparams + n, sizeof(ip)))
369 			return -EFAULT;
370 
371 		/* All unused attribute bits has to be zero */
372 		if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
373 			return -EINVAL;
374 
375 		params[n].attr = ip.attr;
376 		switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
377 		case TEE_IOCTL_PARAM_ATTR_TYPE_NONE:
378 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
379 			break;
380 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
381 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
382 			params[n].u.value.a = ip.a;
383 			params[n].u.value.b = ip.b;
384 			params[n].u.value.c = ip.c;
385 			break;
386 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
387 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
388 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
389 			/*
390 			 * If a NULL pointer is passed to a TA in the TEE,
391 			 * the ip.c IOCTL parameters is set to TEE_MEMREF_NULL
392 			 * indicating a NULL memory reference.
393 			 */
394 			if (ip.c != TEE_MEMREF_NULL) {
395 				/*
396 				 * If we fail to get a pointer to a shared
397 				 * memory object (and increase the ref count)
398 				 * from an identifier we return an error. All
399 				 * pointers that has been added in params have
400 				 * an increased ref count. It's the callers
401 				 * responibility to do tee_shm_put() on all
402 				 * resolved pointers.
403 				 */
404 				shm = tee_shm_get_from_id(ctx, ip.c);
405 				if (IS_ERR(shm))
406 					return PTR_ERR(shm);
407 
408 				/*
409 				 * Ensure offset + size does not overflow
410 				 * offset and does not overflow the size of
411 				 * the referred shared memory object.
412 				 */
413 				if ((ip.a + ip.b) < ip.a ||
414 				    (ip.a + ip.b) > shm->size) {
415 					tee_shm_put(shm);
416 					return -EINVAL;
417 				}
418 			} else if (ctx->cap_memref_null) {
419 				/* Pass NULL pointer to OP-TEE */
420 				shm = NULL;
421 			} else {
422 				return -EINVAL;
423 			}
424 
425 			params[n].u.memref.shm_offs = ip.a;
426 			params[n].u.memref.size = ip.b;
427 			params[n].u.memref.shm = shm;
428 			break;
429 		default:
430 			/* Unknown attribute */
431 			return -EINVAL;
432 		}
433 	}
434 	return 0;
435 }
436 
437 static int params_to_user(struct tee_ioctl_param __user *uparams,
438 			  size_t num_params, struct tee_param *params)
439 {
440 	size_t n;
441 
442 	for (n = 0; n < num_params; n++) {
443 		struct tee_ioctl_param __user *up = uparams + n;
444 		struct tee_param *p = params + n;
445 
446 		switch (p->attr) {
447 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
448 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
449 			if (put_user(p->u.value.a, &up->a) ||
450 			    put_user(p->u.value.b, &up->b) ||
451 			    put_user(p->u.value.c, &up->c))
452 				return -EFAULT;
453 			break;
454 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
455 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
456 			if (put_user((u64)p->u.memref.size, &up->b))
457 				return -EFAULT;
458 			break;
459 		default:
460 			break;
461 		}
462 	}
463 	return 0;
464 }
465 
466 static int tee_ioctl_open_session(struct tee_context *ctx,
467 				  struct tee_ioctl_buf_data __user *ubuf)
468 {
469 	int rc;
470 	size_t n;
471 	struct tee_ioctl_buf_data buf;
472 	struct tee_ioctl_open_session_arg __user *uarg;
473 	struct tee_ioctl_open_session_arg arg;
474 	struct tee_ioctl_param __user *uparams = NULL;
475 	struct tee_param *params = NULL;
476 	bool have_session = false;
477 
478 	if (!ctx->teedev->desc->ops->open_session)
479 		return -EINVAL;
480 
481 	if (copy_from_user(&buf, ubuf, sizeof(buf)))
482 		return -EFAULT;
483 
484 	if (buf.buf_len > TEE_MAX_ARG_SIZE ||
485 	    buf.buf_len < sizeof(struct tee_ioctl_open_session_arg))
486 		return -EINVAL;
487 
488 	uarg = u64_to_user_ptr(buf.buf_ptr);
489 	if (copy_from_user(&arg, uarg, sizeof(arg)))
490 		return -EFAULT;
491 
492 	if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
493 		return -EINVAL;
494 
495 	if (arg.num_params) {
496 		params = kcalloc(arg.num_params, sizeof(struct tee_param),
497 				 GFP_KERNEL);
498 		if (!params)
499 			return -ENOMEM;
500 		uparams = uarg->params;
501 		rc = params_from_user(ctx, params, arg.num_params, uparams);
502 		if (rc)
503 			goto out;
504 	}
505 
506 	if (arg.clnt_login >= TEE_IOCTL_LOGIN_REE_KERNEL_MIN &&
507 	    arg.clnt_login <= TEE_IOCTL_LOGIN_REE_KERNEL_MAX) {
508 		pr_debug("login method not allowed for user-space client\n");
509 		rc = -EPERM;
510 		goto out;
511 	}
512 
513 	rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params);
514 	if (rc)
515 		goto out;
516 	have_session = true;
517 
518 	if (put_user(arg.session, &uarg->session) ||
519 	    put_user(arg.ret, &uarg->ret) ||
520 	    put_user(arg.ret_origin, &uarg->ret_origin)) {
521 		rc = -EFAULT;
522 		goto out;
523 	}
524 	rc = params_to_user(uparams, arg.num_params, params);
525 out:
526 	/*
527 	 * If we've succeeded to open the session but failed to communicate
528 	 * it back to user space, close the session again to avoid leakage.
529 	 */
530 	if (rc && have_session && ctx->teedev->desc->ops->close_session)
531 		ctx->teedev->desc->ops->close_session(ctx, arg.session);
532 
533 	if (params) {
534 		/* Decrease ref count for all valid shared memory pointers */
535 		for (n = 0; n < arg.num_params; n++)
536 			if (tee_param_is_memref(params + n) &&
537 			    params[n].u.memref.shm)
538 				tee_shm_put(params[n].u.memref.shm);
539 		kfree(params);
540 	}
541 
542 	return rc;
543 }
544 
545 static int tee_ioctl_invoke(struct tee_context *ctx,
546 			    struct tee_ioctl_buf_data __user *ubuf)
547 {
548 	int rc;
549 	size_t n;
550 	struct tee_ioctl_buf_data buf;
551 	struct tee_ioctl_invoke_arg __user *uarg;
552 	struct tee_ioctl_invoke_arg arg;
553 	struct tee_ioctl_param __user *uparams = NULL;
554 	struct tee_param *params = NULL;
555 
556 	if (!ctx->teedev->desc->ops->invoke_func)
557 		return -EINVAL;
558 
559 	if (copy_from_user(&buf, ubuf, sizeof(buf)))
560 		return -EFAULT;
561 
562 	if (buf.buf_len > TEE_MAX_ARG_SIZE ||
563 	    buf.buf_len < sizeof(struct tee_ioctl_invoke_arg))
564 		return -EINVAL;
565 
566 	uarg = u64_to_user_ptr(buf.buf_ptr);
567 	if (copy_from_user(&arg, uarg, sizeof(arg)))
568 		return -EFAULT;
569 
570 	if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
571 		return -EINVAL;
572 
573 	if (arg.num_params) {
574 		params = kcalloc(arg.num_params, sizeof(struct tee_param),
575 				 GFP_KERNEL);
576 		if (!params)
577 			return -ENOMEM;
578 		uparams = uarg->params;
579 		rc = params_from_user(ctx, params, arg.num_params, uparams);
580 		if (rc)
581 			goto out;
582 	}
583 
584 	rc = ctx->teedev->desc->ops->invoke_func(ctx, &arg, params);
585 	if (rc)
586 		goto out;
587 
588 	if (put_user(arg.ret, &uarg->ret) ||
589 	    put_user(arg.ret_origin, &uarg->ret_origin)) {
590 		rc = -EFAULT;
591 		goto out;
592 	}
593 	rc = params_to_user(uparams, arg.num_params, params);
594 out:
595 	if (params) {
596 		/* Decrease ref count for all valid shared memory pointers */
597 		for (n = 0; n < arg.num_params; n++)
598 			if (tee_param_is_memref(params + n) &&
599 			    params[n].u.memref.shm)
600 				tee_shm_put(params[n].u.memref.shm);
601 		kfree(params);
602 	}
603 	return rc;
604 }
605 
606 static int tee_ioctl_cancel(struct tee_context *ctx,
607 			    struct tee_ioctl_cancel_arg __user *uarg)
608 {
609 	struct tee_ioctl_cancel_arg arg;
610 
611 	if (!ctx->teedev->desc->ops->cancel_req)
612 		return -EINVAL;
613 
614 	if (copy_from_user(&arg, uarg, sizeof(arg)))
615 		return -EFAULT;
616 
617 	return ctx->teedev->desc->ops->cancel_req(ctx, arg.cancel_id,
618 						  arg.session);
619 }
620 
621 static int
622 tee_ioctl_close_session(struct tee_context *ctx,
623 			struct tee_ioctl_close_session_arg __user *uarg)
624 {
625 	struct tee_ioctl_close_session_arg arg;
626 
627 	if (!ctx->teedev->desc->ops->close_session)
628 		return -EINVAL;
629 
630 	if (copy_from_user(&arg, uarg, sizeof(arg)))
631 		return -EFAULT;
632 
633 	return ctx->teedev->desc->ops->close_session(ctx, arg.session);
634 }
635 
636 static int params_to_supp(struct tee_context *ctx,
637 			  struct tee_ioctl_param __user *uparams,
638 			  size_t num_params, struct tee_param *params)
639 {
640 	size_t n;
641 
642 	for (n = 0; n < num_params; n++) {
643 		struct tee_ioctl_param ip;
644 		struct tee_param *p = params + n;
645 
646 		ip.attr = p->attr;
647 		switch (p->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
648 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
649 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
650 			ip.a = p->u.value.a;
651 			ip.b = p->u.value.b;
652 			ip.c = p->u.value.c;
653 			break;
654 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
655 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
656 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
657 			ip.b = p->u.memref.size;
658 			if (!p->u.memref.shm) {
659 				ip.a = 0;
660 				ip.c = (u64)-1; /* invalid shm id */
661 				break;
662 			}
663 			ip.a = p->u.memref.shm_offs;
664 			ip.c = p->u.memref.shm->id;
665 			break;
666 		default:
667 			ip.a = 0;
668 			ip.b = 0;
669 			ip.c = 0;
670 			break;
671 		}
672 
673 		if (copy_to_user(uparams + n, &ip, sizeof(ip)))
674 			return -EFAULT;
675 	}
676 
677 	return 0;
678 }
679 
680 static int tee_ioctl_supp_recv(struct tee_context *ctx,
681 			       struct tee_ioctl_buf_data __user *ubuf)
682 {
683 	int rc;
684 	struct tee_ioctl_buf_data buf;
685 	struct tee_iocl_supp_recv_arg __user *uarg;
686 	struct tee_param *params;
687 	u32 num_params;
688 	u32 func;
689 
690 	if (!ctx->teedev->desc->ops->supp_recv)
691 		return -EINVAL;
692 
693 	if (copy_from_user(&buf, ubuf, sizeof(buf)))
694 		return -EFAULT;
695 
696 	if (buf.buf_len > TEE_MAX_ARG_SIZE ||
697 	    buf.buf_len < sizeof(struct tee_iocl_supp_recv_arg))
698 		return -EINVAL;
699 
700 	uarg = u64_to_user_ptr(buf.buf_ptr);
701 	if (get_user(num_params, &uarg->num_params))
702 		return -EFAULT;
703 
704 	if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) != buf.buf_len)
705 		return -EINVAL;
706 
707 	params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
708 	if (!params)
709 		return -ENOMEM;
710 
711 	rc = params_from_user(ctx, params, num_params, uarg->params);
712 	if (rc)
713 		goto out;
714 
715 	rc = ctx->teedev->desc->ops->supp_recv(ctx, &func, &num_params, params);
716 	if (rc)
717 		goto out;
718 
719 	if (put_user(func, &uarg->func) ||
720 	    put_user(num_params, &uarg->num_params)) {
721 		rc = -EFAULT;
722 		goto out;
723 	}
724 
725 	rc = params_to_supp(ctx, uarg->params, num_params, params);
726 out:
727 	kfree(params);
728 	return rc;
729 }
730 
731 static int params_from_supp(struct tee_param *params, size_t num_params,
732 			    struct tee_ioctl_param __user *uparams)
733 {
734 	size_t n;
735 
736 	for (n = 0; n < num_params; n++) {
737 		struct tee_param *p = params + n;
738 		struct tee_ioctl_param ip;
739 
740 		if (copy_from_user(&ip, uparams + n, sizeof(ip)))
741 			return -EFAULT;
742 
743 		/* All unused attribute bits has to be zero */
744 		if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
745 			return -EINVAL;
746 
747 		p->attr = ip.attr;
748 		switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
749 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
750 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
751 			/* Only out and in/out values can be updated */
752 			p->u.value.a = ip.a;
753 			p->u.value.b = ip.b;
754 			p->u.value.c = ip.c;
755 			break;
756 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
757 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
758 			/*
759 			 * Only the size of the memref can be updated.
760 			 * Since we don't have access to the original
761 			 * parameters here, only store the supplied size.
762 			 * The driver will copy the updated size into the
763 			 * original parameters.
764 			 */
765 			p->u.memref.shm = NULL;
766 			p->u.memref.shm_offs = 0;
767 			p->u.memref.size = ip.b;
768 			break;
769 		default:
770 			memset(&p->u, 0, sizeof(p->u));
771 			break;
772 		}
773 	}
774 	return 0;
775 }
776 
777 static int tee_ioctl_supp_send(struct tee_context *ctx,
778 			       struct tee_ioctl_buf_data __user *ubuf)
779 {
780 	long rc;
781 	struct tee_ioctl_buf_data buf;
782 	struct tee_iocl_supp_send_arg __user *uarg;
783 	struct tee_param *params;
784 	u32 num_params;
785 	u32 ret;
786 
787 	/* Not valid for this driver */
788 	if (!ctx->teedev->desc->ops->supp_send)
789 		return -EINVAL;
790 
791 	if (copy_from_user(&buf, ubuf, sizeof(buf)))
792 		return -EFAULT;
793 
794 	if (buf.buf_len > TEE_MAX_ARG_SIZE ||
795 	    buf.buf_len < sizeof(struct tee_iocl_supp_send_arg))
796 		return -EINVAL;
797 
798 	uarg = u64_to_user_ptr(buf.buf_ptr);
799 	if (get_user(ret, &uarg->ret) ||
800 	    get_user(num_params, &uarg->num_params))
801 		return -EFAULT;
802 
803 	if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) > buf.buf_len)
804 		return -EINVAL;
805 
806 	params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
807 	if (!params)
808 		return -ENOMEM;
809 
810 	rc = params_from_supp(params, num_params, uarg->params);
811 	if (rc)
812 		goto out;
813 
814 	rc = ctx->teedev->desc->ops->supp_send(ctx, ret, num_params, params);
815 out:
816 	kfree(params);
817 	return rc;
818 }
819 
820 static long tee_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
821 {
822 	struct tee_context *ctx = filp->private_data;
823 	void __user *uarg = (void __user *)arg;
824 
825 	switch (cmd) {
826 	case TEE_IOC_VERSION:
827 		return tee_ioctl_version(ctx, uarg);
828 	case TEE_IOC_SHM_ALLOC:
829 		return tee_ioctl_shm_alloc(ctx, uarg);
830 	case TEE_IOC_SHM_REGISTER:
831 		return tee_ioctl_shm_register(ctx, uarg);
832 	case TEE_IOC_OPEN_SESSION:
833 		return tee_ioctl_open_session(ctx, uarg);
834 	case TEE_IOC_INVOKE:
835 		return tee_ioctl_invoke(ctx, uarg);
836 	case TEE_IOC_CANCEL:
837 		return tee_ioctl_cancel(ctx, uarg);
838 	case TEE_IOC_CLOSE_SESSION:
839 		return tee_ioctl_close_session(ctx, uarg);
840 	case TEE_IOC_SUPPL_RECV:
841 		return tee_ioctl_supp_recv(ctx, uarg);
842 	case TEE_IOC_SUPPL_SEND:
843 		return tee_ioctl_supp_send(ctx, uarg);
844 	default:
845 		return -EINVAL;
846 	}
847 }
848 
849 static const struct file_operations tee_fops = {
850 	.owner = THIS_MODULE,
851 	.open = tee_open,
852 	.release = tee_release,
853 	.unlocked_ioctl = tee_ioctl,
854 	.compat_ioctl = compat_ptr_ioctl,
855 };
856 
857 static void tee_release_device(struct device *dev)
858 {
859 	struct tee_device *teedev = container_of(dev, struct tee_device, dev);
860 
861 	spin_lock(&driver_lock);
862 	clear_bit(teedev->id, dev_mask);
863 	spin_unlock(&driver_lock);
864 	mutex_destroy(&teedev->mutex);
865 	idr_destroy(&teedev->idr);
866 	kfree(teedev);
867 }
868 
869 /**
870  * tee_device_alloc() - Allocate a new struct tee_device instance
871  * @teedesc:	Descriptor for this driver
872  * @dev:	Parent device for this device
873  * @pool:	Shared memory pool, NULL if not used
874  * @driver_data: Private driver data for this device
875  *
876  * Allocates a new struct tee_device instance. The device is
877  * removed by tee_device_unregister().
878  *
879  * @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
880  */
881 struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
882 				    struct device *dev,
883 				    struct tee_shm_pool *pool,
884 				    void *driver_data)
885 {
886 	struct tee_device *teedev;
887 	void *ret;
888 	int rc, max_id;
889 	int offs = 0;
890 
891 	if (!teedesc || !teedesc->name || !teedesc->ops ||
892 	    !teedesc->ops->get_version || !teedesc->ops->open ||
893 	    !teedesc->ops->release || !pool)
894 		return ERR_PTR(-EINVAL);
895 
896 	teedev = kzalloc(sizeof(*teedev), GFP_KERNEL);
897 	if (!teedev) {
898 		ret = ERR_PTR(-ENOMEM);
899 		goto err;
900 	}
901 
902 	max_id = TEE_NUM_DEVICES / 2;
903 
904 	if (teedesc->flags & TEE_DESC_PRIVILEGED) {
905 		offs = TEE_NUM_DEVICES / 2;
906 		max_id = TEE_NUM_DEVICES;
907 	}
908 
909 	spin_lock(&driver_lock);
910 	teedev->id = find_next_zero_bit(dev_mask, max_id, offs);
911 	if (teedev->id < max_id)
912 		set_bit(teedev->id, dev_mask);
913 	spin_unlock(&driver_lock);
914 
915 	if (teedev->id >= max_id) {
916 		ret = ERR_PTR(-ENOMEM);
917 		goto err;
918 	}
919 
920 	snprintf(teedev->name, sizeof(teedev->name), "tee%s%d",
921 		 teedesc->flags & TEE_DESC_PRIVILEGED ? "priv" : "",
922 		 teedev->id - offs);
923 
924 	teedev->dev.class = tee_class;
925 	teedev->dev.release = tee_release_device;
926 	teedev->dev.parent = dev;
927 
928 	teedev->dev.devt = MKDEV(MAJOR(tee_devt), teedev->id);
929 
930 	rc = dev_set_name(&teedev->dev, "%s", teedev->name);
931 	if (rc) {
932 		ret = ERR_PTR(rc);
933 		goto err_devt;
934 	}
935 
936 	cdev_init(&teedev->cdev, &tee_fops);
937 	teedev->cdev.owner = teedesc->owner;
938 
939 	dev_set_drvdata(&teedev->dev, driver_data);
940 	device_initialize(&teedev->dev);
941 
942 	/* 1 as tee_device_unregister() does one final tee_device_put() */
943 	teedev->num_users = 1;
944 	init_completion(&teedev->c_no_users);
945 	mutex_init(&teedev->mutex);
946 	idr_init(&teedev->idr);
947 
948 	teedev->desc = teedesc;
949 	teedev->pool = pool;
950 
951 	return teedev;
952 err_devt:
953 	unregister_chrdev_region(teedev->dev.devt, 1);
954 err:
955 	pr_err("could not register %s driver\n",
956 	       teedesc->flags & TEE_DESC_PRIVILEGED ? "privileged" : "client");
957 	if (teedev && teedev->id < TEE_NUM_DEVICES) {
958 		spin_lock(&driver_lock);
959 		clear_bit(teedev->id, dev_mask);
960 		spin_unlock(&driver_lock);
961 	}
962 	kfree(teedev);
963 	return ret;
964 }
965 EXPORT_SYMBOL_GPL(tee_device_alloc);
966 
967 static ssize_t implementation_id_show(struct device *dev,
968 				      struct device_attribute *attr, char *buf)
969 {
970 	struct tee_device *teedev = container_of(dev, struct tee_device, dev);
971 	struct tee_ioctl_version_data vers;
972 
973 	teedev->desc->ops->get_version(teedev, &vers);
974 	return scnprintf(buf, PAGE_SIZE, "%d\n", vers.impl_id);
975 }
976 static DEVICE_ATTR_RO(implementation_id);
977 
978 static struct attribute *tee_dev_attrs[] = {
979 	&dev_attr_implementation_id.attr,
980 	NULL
981 };
982 
983 ATTRIBUTE_GROUPS(tee_dev);
984 
985 /**
986  * tee_device_register() - Registers a TEE device
987  * @teedev:	Device to register
988  *
989  * tee_device_unregister() need to be called to remove the @teedev if
990  * this function fails.
991  *
992  * @returns < 0 on failure
993  */
994 int tee_device_register(struct tee_device *teedev)
995 {
996 	int rc;
997 
998 	if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
999 		dev_err(&teedev->dev, "attempt to register twice\n");
1000 		return -EINVAL;
1001 	}
1002 
1003 	teedev->dev.groups = tee_dev_groups;
1004 
1005 	rc = cdev_device_add(&teedev->cdev, &teedev->dev);
1006 	if (rc) {
1007 		dev_err(&teedev->dev,
1008 			"unable to cdev_device_add() %s, major %d, minor %d, err=%d\n",
1009 			teedev->name, MAJOR(teedev->dev.devt),
1010 			MINOR(teedev->dev.devt), rc);
1011 		return rc;
1012 	}
1013 
1014 	teedev->flags |= TEE_DEVICE_FLAG_REGISTERED;
1015 	return 0;
1016 }
1017 EXPORT_SYMBOL_GPL(tee_device_register);
1018 
1019 void tee_device_put(struct tee_device *teedev)
1020 {
1021 	mutex_lock(&teedev->mutex);
1022 	/* Shouldn't put in this state */
1023 	if (!WARN_ON(!teedev->desc)) {
1024 		teedev->num_users--;
1025 		if (!teedev->num_users) {
1026 			teedev->desc = NULL;
1027 			complete(&teedev->c_no_users);
1028 		}
1029 	}
1030 	mutex_unlock(&teedev->mutex);
1031 }
1032 
1033 bool tee_device_get(struct tee_device *teedev)
1034 {
1035 	mutex_lock(&teedev->mutex);
1036 	if (!teedev->desc) {
1037 		mutex_unlock(&teedev->mutex);
1038 		return false;
1039 	}
1040 	teedev->num_users++;
1041 	mutex_unlock(&teedev->mutex);
1042 	return true;
1043 }
1044 
1045 /**
1046  * tee_device_unregister() - Removes a TEE device
1047  * @teedev:	Device to unregister
1048  *
1049  * This function should be called to remove the @teedev even if
1050  * tee_device_register() hasn't been called yet. Does nothing if
1051  * @teedev is NULL.
1052  */
1053 void tee_device_unregister(struct tee_device *teedev)
1054 {
1055 	if (!teedev)
1056 		return;
1057 
1058 	if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED)
1059 		cdev_device_del(&teedev->cdev, &teedev->dev);
1060 
1061 	tee_device_put(teedev);
1062 	wait_for_completion(&teedev->c_no_users);
1063 
1064 	/*
1065 	 * No need to take a mutex any longer now since teedev->desc was
1066 	 * set to NULL before teedev->c_no_users was completed.
1067 	 */
1068 
1069 	teedev->pool = NULL;
1070 
1071 	put_device(&teedev->dev);
1072 }
1073 EXPORT_SYMBOL_GPL(tee_device_unregister);
1074 
1075 /**
1076  * tee_get_drvdata() - Return driver_data pointer
1077  * @teedev:	Device containing the driver_data pointer
1078  * @returns the driver_data pointer supplied to tee_register().
1079  */
1080 void *tee_get_drvdata(struct tee_device *teedev)
1081 {
1082 	return dev_get_drvdata(&teedev->dev);
1083 }
1084 EXPORT_SYMBOL_GPL(tee_get_drvdata);
1085 
1086 struct match_dev_data {
1087 	struct tee_ioctl_version_data *vers;
1088 	const void *data;
1089 	int (*match)(struct tee_ioctl_version_data *, const void *);
1090 };
1091 
1092 static int match_dev(struct device *dev, const void *data)
1093 {
1094 	const struct match_dev_data *match_data = data;
1095 	struct tee_device *teedev = container_of(dev, struct tee_device, dev);
1096 
1097 	teedev->desc->ops->get_version(teedev, match_data->vers);
1098 	return match_data->match(match_data->vers, match_data->data);
1099 }
1100 
1101 struct tee_context *
1102 tee_client_open_context(struct tee_context *start,
1103 			int (*match)(struct tee_ioctl_version_data *,
1104 				     const void *),
1105 			const void *data, struct tee_ioctl_version_data *vers)
1106 {
1107 	struct device *dev = NULL;
1108 	struct device *put_dev = NULL;
1109 	struct tee_context *ctx = NULL;
1110 	struct tee_ioctl_version_data v;
1111 	struct match_dev_data match_data = { vers ? vers : &v, data, match };
1112 
1113 	if (start)
1114 		dev = &start->teedev->dev;
1115 
1116 	do {
1117 		dev = class_find_device(tee_class, dev, &match_data, match_dev);
1118 		if (!dev) {
1119 			ctx = ERR_PTR(-ENOENT);
1120 			break;
1121 		}
1122 
1123 		put_device(put_dev);
1124 		put_dev = dev;
1125 
1126 		ctx = teedev_open(container_of(dev, struct tee_device, dev));
1127 	} while (IS_ERR(ctx) && PTR_ERR(ctx) != -ENOMEM);
1128 
1129 	put_device(put_dev);
1130 	/*
1131 	 * Default behaviour for in kernel client is to not wait for
1132 	 * tee-supplicant if not present for any requests in this context.
1133 	 * Also this flag could be configured again before call to
1134 	 * tee_client_open_session() if any in kernel client requires
1135 	 * different behaviour.
1136 	 */
1137 	if (!IS_ERR(ctx))
1138 		ctx->supp_nowait = true;
1139 
1140 	return ctx;
1141 }
1142 EXPORT_SYMBOL_GPL(tee_client_open_context);
1143 
1144 void tee_client_close_context(struct tee_context *ctx)
1145 {
1146 	teedev_close_context(ctx);
1147 }
1148 EXPORT_SYMBOL_GPL(tee_client_close_context);
1149 
1150 void tee_client_get_version(struct tee_context *ctx,
1151 			    struct tee_ioctl_version_data *vers)
1152 {
1153 	ctx->teedev->desc->ops->get_version(ctx->teedev, vers);
1154 }
1155 EXPORT_SYMBOL_GPL(tee_client_get_version);
1156 
1157 int tee_client_open_session(struct tee_context *ctx,
1158 			    struct tee_ioctl_open_session_arg *arg,
1159 			    struct tee_param *param)
1160 {
1161 	if (!ctx->teedev->desc->ops->open_session)
1162 		return -EINVAL;
1163 	return ctx->teedev->desc->ops->open_session(ctx, arg, param);
1164 }
1165 EXPORT_SYMBOL_GPL(tee_client_open_session);
1166 
1167 int tee_client_close_session(struct tee_context *ctx, u32 session)
1168 {
1169 	if (!ctx->teedev->desc->ops->close_session)
1170 		return -EINVAL;
1171 	return ctx->teedev->desc->ops->close_session(ctx, session);
1172 }
1173 EXPORT_SYMBOL_GPL(tee_client_close_session);
1174 
1175 int tee_client_invoke_func(struct tee_context *ctx,
1176 			   struct tee_ioctl_invoke_arg *arg,
1177 			   struct tee_param *param)
1178 {
1179 	if (!ctx->teedev->desc->ops->invoke_func)
1180 		return -EINVAL;
1181 	return ctx->teedev->desc->ops->invoke_func(ctx, arg, param);
1182 }
1183 EXPORT_SYMBOL_GPL(tee_client_invoke_func);
1184 
1185 int tee_client_cancel_req(struct tee_context *ctx,
1186 			  struct tee_ioctl_cancel_arg *arg)
1187 {
1188 	if (!ctx->teedev->desc->ops->cancel_req)
1189 		return -EINVAL;
1190 	return ctx->teedev->desc->ops->cancel_req(ctx, arg->cancel_id,
1191 						  arg->session);
1192 }
1193 
1194 static int tee_client_device_match(struct device *dev,
1195 				   struct device_driver *drv)
1196 {
1197 	const struct tee_client_device_id *id_table;
1198 	struct tee_client_device *tee_device;
1199 
1200 	id_table = to_tee_client_driver(drv)->id_table;
1201 	tee_device = to_tee_client_device(dev);
1202 
1203 	while (!uuid_is_null(&id_table->uuid)) {
1204 		if (uuid_equal(&tee_device->id.uuid, &id_table->uuid))
1205 			return 1;
1206 		id_table++;
1207 	}
1208 
1209 	return 0;
1210 }
1211 
1212 static int tee_client_device_uevent(struct device *dev,
1213 				    struct kobj_uevent_env *env)
1214 {
1215 	uuid_t *dev_id = &to_tee_client_device(dev)->id.uuid;
1216 
1217 	return add_uevent_var(env, "MODALIAS=tee:%pUb", dev_id);
1218 }
1219 
1220 struct bus_type tee_bus_type = {
1221 	.name		= "tee",
1222 	.match		= tee_client_device_match,
1223 	.uevent		= tee_client_device_uevent,
1224 };
1225 EXPORT_SYMBOL_GPL(tee_bus_type);
1226 
1227 static int __init tee_init(void)
1228 {
1229 	int rc;
1230 
1231 	tee_class = class_create(THIS_MODULE, "tee");
1232 	if (IS_ERR(tee_class)) {
1233 		pr_err("couldn't create class\n");
1234 		return PTR_ERR(tee_class);
1235 	}
1236 
1237 	rc = alloc_chrdev_region(&tee_devt, 0, TEE_NUM_DEVICES, "tee");
1238 	if (rc) {
1239 		pr_err("failed to allocate char dev region\n");
1240 		goto out_unreg_class;
1241 	}
1242 
1243 	rc = bus_register(&tee_bus_type);
1244 	if (rc) {
1245 		pr_err("failed to register tee bus\n");
1246 		goto out_unreg_chrdev;
1247 	}
1248 
1249 	return 0;
1250 
1251 out_unreg_chrdev:
1252 	unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1253 out_unreg_class:
1254 	class_destroy(tee_class);
1255 	tee_class = NULL;
1256 
1257 	return rc;
1258 }
1259 
1260 static void __exit tee_exit(void)
1261 {
1262 	bus_unregister(&tee_bus_type);
1263 	unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1264 	class_destroy(tee_class);
1265 	tee_class = NULL;
1266 }
1267 
1268 subsys_initcall(tee_init);
1269 module_exit(tee_exit);
1270 
1271 MODULE_AUTHOR("Linaro");
1272 MODULE_DESCRIPTION("TEE Driver");
1273 MODULE_VERSION("1.0");
1274 MODULE_LICENSE("GPL v2");
1275