xref: /kernel/linux/linux-6.6/drivers/tee/tee_core.c (revision 62306a36)
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2015-2016, Linaro Limited
4 */
5
6#define pr_fmt(fmt) "%s: " fmt, __func__
7
8#include <linux/cdev.h>
9#include <linux/cred.h>
10#include <linux/fs.h>
11#include <linux/idr.h>
12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/tee_drv.h>
15#include <linux/uaccess.h>
16#include <crypto/hash.h>
17#include <crypto/sha1.h>
18#include "tee_private.h"
19
20#define TEE_NUM_DEVICES	32
21
22#define TEE_IOCTL_PARAM_SIZE(x) (sizeof(struct tee_param) * (x))
23
24#define TEE_UUID_NS_NAME_SIZE	128
25
26/*
27 * TEE Client UUID name space identifier (UUIDv4)
28 *
29 * Value here is random UUID that is allocated as name space identifier for
30 * forming Client UUID's for TEE environment using UUIDv5 scheme.
31 */
32static const uuid_t tee_client_uuid_ns = UUID_INIT(0x58ac9ca0, 0x2086, 0x4683,
33						   0xa1, 0xb8, 0xec, 0x4b,
34						   0xc0, 0x8e, 0x01, 0xb6);
35
36/*
37 * Unprivileged devices in the lower half range and privileged devices in
38 * the upper half range.
39 */
40static DECLARE_BITMAP(dev_mask, TEE_NUM_DEVICES);
41static DEFINE_SPINLOCK(driver_lock);
42
43static struct class *tee_class;
44static dev_t tee_devt;
45
46struct tee_context *teedev_open(struct tee_device *teedev)
47{
48	int rc;
49	struct tee_context *ctx;
50
51	if (!tee_device_get(teedev))
52		return ERR_PTR(-EINVAL);
53
54	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
55	if (!ctx) {
56		rc = -ENOMEM;
57		goto err;
58	}
59
60	kref_init(&ctx->refcount);
61	ctx->teedev = teedev;
62	rc = teedev->desc->ops->open(ctx);
63	if (rc)
64		goto err;
65
66	return ctx;
67err:
68	kfree(ctx);
69	tee_device_put(teedev);
70	return ERR_PTR(rc);
71
72}
73EXPORT_SYMBOL_GPL(teedev_open);
74
75void teedev_ctx_get(struct tee_context *ctx)
76{
77	if (ctx->releasing)
78		return;
79
80	kref_get(&ctx->refcount);
81}
82
83static 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
92void 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
100void 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}
107EXPORT_SYMBOL_GPL(teedev_close_context);
108
109static 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
126static 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 */
144static 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
190out_free_desc:
191	kfree(desc);
192
193out_free_shash:
194	crypto_free_shash(shash);
195	return rc;
196}
197
198int 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);
263out_free_name:
264	kfree(name);
265
266	return rc;
267}
268EXPORT_SYMBOL_GPL(tee_session_calc_client_uuid);
269
270static 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
286static 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.size = shm->size;
306
307	if (copy_to_user(udata, &data, sizeof(data)))
308		ret = -EFAULT;
309	else
310		ret = tee_shm_get_fd(shm);
311
312	/*
313	 * When user space closes the file descriptor the shared memory
314	 * should be freed or if tee_shm_get_fd() failed then it will
315	 * be freed immediately.
316	 */
317	tee_shm_put(shm);
318	return ret;
319}
320
321static int
322tee_ioctl_shm_register(struct tee_context *ctx,
323		       struct tee_ioctl_shm_register_data __user *udata)
324{
325	long ret;
326	struct tee_ioctl_shm_register_data data;
327	struct tee_shm *shm;
328
329	if (copy_from_user(&data, udata, sizeof(data)))
330		return -EFAULT;
331
332	/* Currently no input flags are supported */
333	if (data.flags)
334		return -EINVAL;
335
336	shm = tee_shm_register_user_buf(ctx, data.addr, data.length);
337	if (IS_ERR(shm))
338		return PTR_ERR(shm);
339
340	data.id = shm->id;
341	data.length = shm->size;
342
343	if (copy_to_user(udata, &data, sizeof(data)))
344		ret = -EFAULT;
345	else
346		ret = tee_shm_get_fd(shm);
347	/*
348	 * When user space closes the file descriptor the shared memory
349	 * should be freed or if tee_shm_get_fd() failed then it will
350	 * be freed immediately.
351	 */
352	tee_shm_put(shm);
353	return ret;
354}
355
356static int params_from_user(struct tee_context *ctx, struct tee_param *params,
357			    size_t num_params,
358			    struct tee_ioctl_param __user *uparams)
359{
360	size_t n;
361
362	for (n = 0; n < num_params; n++) {
363		struct tee_shm *shm;
364		struct tee_ioctl_param ip;
365
366		if (copy_from_user(&ip, uparams + n, sizeof(ip)))
367			return -EFAULT;
368
369		/* All unused attribute bits has to be zero */
370		if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
371			return -EINVAL;
372
373		params[n].attr = ip.attr;
374		switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
375		case TEE_IOCTL_PARAM_ATTR_TYPE_NONE:
376		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
377			break;
378		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
379		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
380			params[n].u.value.a = ip.a;
381			params[n].u.value.b = ip.b;
382			params[n].u.value.c = ip.c;
383			break;
384		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
385		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
386		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
387			/*
388			 * If a NULL pointer is passed to a TA in the TEE,
389			 * the ip.c IOCTL parameters is set to TEE_MEMREF_NULL
390			 * indicating a NULL memory reference.
391			 */
392			if (ip.c != TEE_MEMREF_NULL) {
393				/*
394				 * If we fail to get a pointer to a shared
395				 * memory object (and increase the ref count)
396				 * from an identifier we return an error. All
397				 * pointers that has been added in params have
398				 * an increased ref count. It's the callers
399				 * responibility to do tee_shm_put() on all
400				 * resolved pointers.
401				 */
402				shm = tee_shm_get_from_id(ctx, ip.c);
403				if (IS_ERR(shm))
404					return PTR_ERR(shm);
405
406				/*
407				 * Ensure offset + size does not overflow
408				 * offset and does not overflow the size of
409				 * the referred shared memory object.
410				 */
411				if ((ip.a + ip.b) < ip.a ||
412				    (ip.a + ip.b) > shm->size) {
413					tee_shm_put(shm);
414					return -EINVAL;
415				}
416			} else if (ctx->cap_memref_null) {
417				/* Pass NULL pointer to OP-TEE */
418				shm = NULL;
419			} else {
420				return -EINVAL;
421			}
422
423			params[n].u.memref.shm_offs = ip.a;
424			params[n].u.memref.size = ip.b;
425			params[n].u.memref.shm = shm;
426			break;
427		default:
428			/* Unknown attribute */
429			return -EINVAL;
430		}
431	}
432	return 0;
433}
434
435static int params_to_user(struct tee_ioctl_param __user *uparams,
436			  size_t num_params, struct tee_param *params)
437{
438	size_t n;
439
440	for (n = 0; n < num_params; n++) {
441		struct tee_ioctl_param __user *up = uparams + n;
442		struct tee_param *p = params + n;
443
444		switch (p->attr) {
445		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
446		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
447			if (put_user(p->u.value.a, &up->a) ||
448			    put_user(p->u.value.b, &up->b) ||
449			    put_user(p->u.value.c, &up->c))
450				return -EFAULT;
451			break;
452		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
453		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
454			if (put_user((u64)p->u.memref.size, &up->b))
455				return -EFAULT;
456			break;
457		default:
458			break;
459		}
460	}
461	return 0;
462}
463
464static int tee_ioctl_open_session(struct tee_context *ctx,
465				  struct tee_ioctl_buf_data __user *ubuf)
466{
467	int rc;
468	size_t n;
469	struct tee_ioctl_buf_data buf;
470	struct tee_ioctl_open_session_arg __user *uarg;
471	struct tee_ioctl_open_session_arg arg;
472	struct tee_ioctl_param __user *uparams = NULL;
473	struct tee_param *params = NULL;
474	bool have_session = false;
475
476	if (!ctx->teedev->desc->ops->open_session)
477		return -EINVAL;
478
479	if (copy_from_user(&buf, ubuf, sizeof(buf)))
480		return -EFAULT;
481
482	if (buf.buf_len > TEE_MAX_ARG_SIZE ||
483	    buf.buf_len < sizeof(struct tee_ioctl_open_session_arg))
484		return -EINVAL;
485
486	uarg = u64_to_user_ptr(buf.buf_ptr);
487	if (copy_from_user(&arg, uarg, sizeof(arg)))
488		return -EFAULT;
489
490	if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
491		return -EINVAL;
492
493	if (arg.num_params) {
494		params = kcalloc(arg.num_params, sizeof(struct tee_param),
495				 GFP_KERNEL);
496		if (!params)
497			return -ENOMEM;
498		uparams = uarg->params;
499		rc = params_from_user(ctx, params, arg.num_params, uparams);
500		if (rc)
501			goto out;
502	}
503
504	if (arg.clnt_login >= TEE_IOCTL_LOGIN_REE_KERNEL_MIN &&
505	    arg.clnt_login <= TEE_IOCTL_LOGIN_REE_KERNEL_MAX) {
506		pr_debug("login method not allowed for user-space client\n");
507		rc = -EPERM;
508		goto out;
509	}
510
511	rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params);
512	if (rc)
513		goto out;
514	have_session = true;
515
516	if (put_user(arg.session, &uarg->session) ||
517	    put_user(arg.ret, &uarg->ret) ||
518	    put_user(arg.ret_origin, &uarg->ret_origin)) {
519		rc = -EFAULT;
520		goto out;
521	}
522	rc = params_to_user(uparams, arg.num_params, params);
523out:
524	/*
525	 * If we've succeeded to open the session but failed to communicate
526	 * it back to user space, close the session again to avoid leakage.
527	 */
528	if (rc && have_session && ctx->teedev->desc->ops->close_session)
529		ctx->teedev->desc->ops->close_session(ctx, arg.session);
530
531	if (params) {
532		/* Decrease ref count for all valid shared memory pointers */
533		for (n = 0; n < arg.num_params; n++)
534			if (tee_param_is_memref(params + n) &&
535			    params[n].u.memref.shm)
536				tee_shm_put(params[n].u.memref.shm);
537		kfree(params);
538	}
539
540	return rc;
541}
542
543static int tee_ioctl_invoke(struct tee_context *ctx,
544			    struct tee_ioctl_buf_data __user *ubuf)
545{
546	int rc;
547	size_t n;
548	struct tee_ioctl_buf_data buf;
549	struct tee_ioctl_invoke_arg __user *uarg;
550	struct tee_ioctl_invoke_arg arg;
551	struct tee_ioctl_param __user *uparams = NULL;
552	struct tee_param *params = NULL;
553
554	if (!ctx->teedev->desc->ops->invoke_func)
555		return -EINVAL;
556
557	if (copy_from_user(&buf, ubuf, sizeof(buf)))
558		return -EFAULT;
559
560	if (buf.buf_len > TEE_MAX_ARG_SIZE ||
561	    buf.buf_len < sizeof(struct tee_ioctl_invoke_arg))
562		return -EINVAL;
563
564	uarg = u64_to_user_ptr(buf.buf_ptr);
565	if (copy_from_user(&arg, uarg, sizeof(arg)))
566		return -EFAULT;
567
568	if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
569		return -EINVAL;
570
571	if (arg.num_params) {
572		params = kcalloc(arg.num_params, sizeof(struct tee_param),
573				 GFP_KERNEL);
574		if (!params)
575			return -ENOMEM;
576		uparams = uarg->params;
577		rc = params_from_user(ctx, params, arg.num_params, uparams);
578		if (rc)
579			goto out;
580	}
581
582	rc = ctx->teedev->desc->ops->invoke_func(ctx, &arg, params);
583	if (rc)
584		goto out;
585
586	if (put_user(arg.ret, &uarg->ret) ||
587	    put_user(arg.ret_origin, &uarg->ret_origin)) {
588		rc = -EFAULT;
589		goto out;
590	}
591	rc = params_to_user(uparams, arg.num_params, params);
592out:
593	if (params) {
594		/* Decrease ref count for all valid shared memory pointers */
595		for (n = 0; n < arg.num_params; n++)
596			if (tee_param_is_memref(params + n) &&
597			    params[n].u.memref.shm)
598				tee_shm_put(params[n].u.memref.shm);
599		kfree(params);
600	}
601	return rc;
602}
603
604static int tee_ioctl_cancel(struct tee_context *ctx,
605			    struct tee_ioctl_cancel_arg __user *uarg)
606{
607	struct tee_ioctl_cancel_arg arg;
608
609	if (!ctx->teedev->desc->ops->cancel_req)
610		return -EINVAL;
611
612	if (copy_from_user(&arg, uarg, sizeof(arg)))
613		return -EFAULT;
614
615	return ctx->teedev->desc->ops->cancel_req(ctx, arg.cancel_id,
616						  arg.session);
617}
618
619static int
620tee_ioctl_close_session(struct tee_context *ctx,
621			struct tee_ioctl_close_session_arg __user *uarg)
622{
623	struct tee_ioctl_close_session_arg arg;
624
625	if (!ctx->teedev->desc->ops->close_session)
626		return -EINVAL;
627
628	if (copy_from_user(&arg, uarg, sizeof(arg)))
629		return -EFAULT;
630
631	return ctx->teedev->desc->ops->close_session(ctx, arg.session);
632}
633
634static int params_to_supp(struct tee_context *ctx,
635			  struct tee_ioctl_param __user *uparams,
636			  size_t num_params, struct tee_param *params)
637{
638	size_t n;
639
640	for (n = 0; n < num_params; n++) {
641		struct tee_ioctl_param ip;
642		struct tee_param *p = params + n;
643
644		ip.attr = p->attr;
645		switch (p->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
646		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
647		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
648			ip.a = p->u.value.a;
649			ip.b = p->u.value.b;
650			ip.c = p->u.value.c;
651			break;
652		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
653		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
654		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
655			ip.b = p->u.memref.size;
656			if (!p->u.memref.shm) {
657				ip.a = 0;
658				ip.c = (u64)-1; /* invalid shm id */
659				break;
660			}
661			ip.a = p->u.memref.shm_offs;
662			ip.c = p->u.memref.shm->id;
663			break;
664		default:
665			ip.a = 0;
666			ip.b = 0;
667			ip.c = 0;
668			break;
669		}
670
671		if (copy_to_user(uparams + n, &ip, sizeof(ip)))
672			return -EFAULT;
673	}
674
675	return 0;
676}
677
678static int tee_ioctl_supp_recv(struct tee_context *ctx,
679			       struct tee_ioctl_buf_data __user *ubuf)
680{
681	int rc;
682	struct tee_ioctl_buf_data buf;
683	struct tee_iocl_supp_recv_arg __user *uarg;
684	struct tee_param *params;
685	u32 num_params;
686	u32 func;
687
688	if (!ctx->teedev->desc->ops->supp_recv)
689		return -EINVAL;
690
691	if (copy_from_user(&buf, ubuf, sizeof(buf)))
692		return -EFAULT;
693
694	if (buf.buf_len > TEE_MAX_ARG_SIZE ||
695	    buf.buf_len < sizeof(struct tee_iocl_supp_recv_arg))
696		return -EINVAL;
697
698	uarg = u64_to_user_ptr(buf.buf_ptr);
699	if (get_user(num_params, &uarg->num_params))
700		return -EFAULT;
701
702	if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) != buf.buf_len)
703		return -EINVAL;
704
705	params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
706	if (!params)
707		return -ENOMEM;
708
709	rc = params_from_user(ctx, params, num_params, uarg->params);
710	if (rc)
711		goto out;
712
713	rc = ctx->teedev->desc->ops->supp_recv(ctx, &func, &num_params, params);
714	if (rc)
715		goto out;
716
717	if (put_user(func, &uarg->func) ||
718	    put_user(num_params, &uarg->num_params)) {
719		rc = -EFAULT;
720		goto out;
721	}
722
723	rc = params_to_supp(ctx, uarg->params, num_params, params);
724out:
725	kfree(params);
726	return rc;
727}
728
729static int params_from_supp(struct tee_param *params, size_t num_params,
730			    struct tee_ioctl_param __user *uparams)
731{
732	size_t n;
733
734	for (n = 0; n < num_params; n++) {
735		struct tee_param *p = params + n;
736		struct tee_ioctl_param ip;
737
738		if (copy_from_user(&ip, uparams + n, sizeof(ip)))
739			return -EFAULT;
740
741		/* All unused attribute bits has to be zero */
742		if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
743			return -EINVAL;
744
745		p->attr = ip.attr;
746		switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
747		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
748		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
749			/* Only out and in/out values can be updated */
750			p->u.value.a = ip.a;
751			p->u.value.b = ip.b;
752			p->u.value.c = ip.c;
753			break;
754		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
755		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
756			/*
757			 * Only the size of the memref can be updated.
758			 * Since we don't have access to the original
759			 * parameters here, only store the supplied size.
760			 * The driver will copy the updated size into the
761			 * original parameters.
762			 */
763			p->u.memref.shm = NULL;
764			p->u.memref.shm_offs = 0;
765			p->u.memref.size = ip.b;
766			break;
767		default:
768			memset(&p->u, 0, sizeof(p->u));
769			break;
770		}
771	}
772	return 0;
773}
774
775static int tee_ioctl_supp_send(struct tee_context *ctx,
776			       struct tee_ioctl_buf_data __user *ubuf)
777{
778	long rc;
779	struct tee_ioctl_buf_data buf;
780	struct tee_iocl_supp_send_arg __user *uarg;
781	struct tee_param *params;
782	u32 num_params;
783	u32 ret;
784
785	/* Not valid for this driver */
786	if (!ctx->teedev->desc->ops->supp_send)
787		return -EINVAL;
788
789	if (copy_from_user(&buf, ubuf, sizeof(buf)))
790		return -EFAULT;
791
792	if (buf.buf_len > TEE_MAX_ARG_SIZE ||
793	    buf.buf_len < sizeof(struct tee_iocl_supp_send_arg))
794		return -EINVAL;
795
796	uarg = u64_to_user_ptr(buf.buf_ptr);
797	if (get_user(ret, &uarg->ret) ||
798	    get_user(num_params, &uarg->num_params))
799		return -EFAULT;
800
801	if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) > buf.buf_len)
802		return -EINVAL;
803
804	params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
805	if (!params)
806		return -ENOMEM;
807
808	rc = params_from_supp(params, num_params, uarg->params);
809	if (rc)
810		goto out;
811
812	rc = ctx->teedev->desc->ops->supp_send(ctx, ret, num_params, params);
813out:
814	kfree(params);
815	return rc;
816}
817
818static long tee_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
819{
820	struct tee_context *ctx = filp->private_data;
821	void __user *uarg = (void __user *)arg;
822
823	switch (cmd) {
824	case TEE_IOC_VERSION:
825		return tee_ioctl_version(ctx, uarg);
826	case TEE_IOC_SHM_ALLOC:
827		return tee_ioctl_shm_alloc(ctx, uarg);
828	case TEE_IOC_SHM_REGISTER:
829		return tee_ioctl_shm_register(ctx, uarg);
830	case TEE_IOC_OPEN_SESSION:
831		return tee_ioctl_open_session(ctx, uarg);
832	case TEE_IOC_INVOKE:
833		return tee_ioctl_invoke(ctx, uarg);
834	case TEE_IOC_CANCEL:
835		return tee_ioctl_cancel(ctx, uarg);
836	case TEE_IOC_CLOSE_SESSION:
837		return tee_ioctl_close_session(ctx, uarg);
838	case TEE_IOC_SUPPL_RECV:
839		return tee_ioctl_supp_recv(ctx, uarg);
840	case TEE_IOC_SUPPL_SEND:
841		return tee_ioctl_supp_send(ctx, uarg);
842	default:
843		return -EINVAL;
844	}
845}
846
847static const struct file_operations tee_fops = {
848	.owner = THIS_MODULE,
849	.open = tee_open,
850	.release = tee_release,
851	.unlocked_ioctl = tee_ioctl,
852	.compat_ioctl = compat_ptr_ioctl,
853};
854
855static void tee_release_device(struct device *dev)
856{
857	struct tee_device *teedev = container_of(dev, struct tee_device, dev);
858
859	spin_lock(&driver_lock);
860	clear_bit(teedev->id, dev_mask);
861	spin_unlock(&driver_lock);
862	mutex_destroy(&teedev->mutex);
863	idr_destroy(&teedev->idr);
864	kfree(teedev);
865}
866
867/**
868 * tee_device_alloc() - Allocate a new struct tee_device instance
869 * @teedesc:	Descriptor for this driver
870 * @dev:	Parent device for this device
871 * @pool:	Shared memory pool, NULL if not used
872 * @driver_data: Private driver data for this device
873 *
874 * Allocates a new struct tee_device instance. The device is
875 * removed by tee_device_unregister().
876 *
877 * @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
878 */
879struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
880				    struct device *dev,
881				    struct tee_shm_pool *pool,
882				    void *driver_data)
883{
884	struct tee_device *teedev;
885	void *ret;
886	int rc, max_id;
887	int offs = 0;
888
889	if (!teedesc || !teedesc->name || !teedesc->ops ||
890	    !teedesc->ops->get_version || !teedesc->ops->open ||
891	    !teedesc->ops->release || !pool)
892		return ERR_PTR(-EINVAL);
893
894	teedev = kzalloc(sizeof(*teedev), GFP_KERNEL);
895	if (!teedev) {
896		ret = ERR_PTR(-ENOMEM);
897		goto err;
898	}
899
900	max_id = TEE_NUM_DEVICES / 2;
901
902	if (teedesc->flags & TEE_DESC_PRIVILEGED) {
903		offs = TEE_NUM_DEVICES / 2;
904		max_id = TEE_NUM_DEVICES;
905	}
906
907	spin_lock(&driver_lock);
908	teedev->id = find_next_zero_bit(dev_mask, max_id, offs);
909	if (teedev->id < max_id)
910		set_bit(teedev->id, dev_mask);
911	spin_unlock(&driver_lock);
912
913	if (teedev->id >= max_id) {
914		ret = ERR_PTR(-ENOMEM);
915		goto err;
916	}
917
918	snprintf(teedev->name, sizeof(teedev->name), "tee%s%d",
919		 teedesc->flags & TEE_DESC_PRIVILEGED ? "priv" : "",
920		 teedev->id - offs);
921
922	teedev->dev.class = tee_class;
923	teedev->dev.release = tee_release_device;
924	teedev->dev.parent = dev;
925
926	teedev->dev.devt = MKDEV(MAJOR(tee_devt), teedev->id);
927
928	rc = dev_set_name(&teedev->dev, "%s", teedev->name);
929	if (rc) {
930		ret = ERR_PTR(rc);
931		goto err_devt;
932	}
933
934	cdev_init(&teedev->cdev, &tee_fops);
935	teedev->cdev.owner = teedesc->owner;
936
937	dev_set_drvdata(&teedev->dev, driver_data);
938	device_initialize(&teedev->dev);
939
940	/* 1 as tee_device_unregister() does one final tee_device_put() */
941	teedev->num_users = 1;
942	init_completion(&teedev->c_no_users);
943	mutex_init(&teedev->mutex);
944	idr_init(&teedev->idr);
945
946	teedev->desc = teedesc;
947	teedev->pool = pool;
948
949	return teedev;
950err_devt:
951	unregister_chrdev_region(teedev->dev.devt, 1);
952err:
953	pr_err("could not register %s driver\n",
954	       teedesc->flags & TEE_DESC_PRIVILEGED ? "privileged" : "client");
955	if (teedev && teedev->id < TEE_NUM_DEVICES) {
956		spin_lock(&driver_lock);
957		clear_bit(teedev->id, dev_mask);
958		spin_unlock(&driver_lock);
959	}
960	kfree(teedev);
961	return ret;
962}
963EXPORT_SYMBOL_GPL(tee_device_alloc);
964
965static ssize_t implementation_id_show(struct device *dev,
966				      struct device_attribute *attr, char *buf)
967{
968	struct tee_device *teedev = container_of(dev, struct tee_device, dev);
969	struct tee_ioctl_version_data vers;
970
971	teedev->desc->ops->get_version(teedev, &vers);
972	return scnprintf(buf, PAGE_SIZE, "%d\n", vers.impl_id);
973}
974static DEVICE_ATTR_RO(implementation_id);
975
976static struct attribute *tee_dev_attrs[] = {
977	&dev_attr_implementation_id.attr,
978	NULL
979};
980
981ATTRIBUTE_GROUPS(tee_dev);
982
983/**
984 * tee_device_register() - Registers a TEE device
985 * @teedev:	Device to register
986 *
987 * tee_device_unregister() need to be called to remove the @teedev if
988 * this function fails.
989 *
990 * @returns < 0 on failure
991 */
992int tee_device_register(struct tee_device *teedev)
993{
994	int rc;
995
996	if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
997		dev_err(&teedev->dev, "attempt to register twice\n");
998		return -EINVAL;
999	}
1000
1001	teedev->dev.groups = tee_dev_groups;
1002
1003	rc = cdev_device_add(&teedev->cdev, &teedev->dev);
1004	if (rc) {
1005		dev_err(&teedev->dev,
1006			"unable to cdev_device_add() %s, major %d, minor %d, err=%d\n",
1007			teedev->name, MAJOR(teedev->dev.devt),
1008			MINOR(teedev->dev.devt), rc);
1009		return rc;
1010	}
1011
1012	teedev->flags |= TEE_DEVICE_FLAG_REGISTERED;
1013	return 0;
1014}
1015EXPORT_SYMBOL_GPL(tee_device_register);
1016
1017void tee_device_put(struct tee_device *teedev)
1018{
1019	mutex_lock(&teedev->mutex);
1020	/* Shouldn't put in this state */
1021	if (!WARN_ON(!teedev->desc)) {
1022		teedev->num_users--;
1023		if (!teedev->num_users) {
1024			teedev->desc = NULL;
1025			complete(&teedev->c_no_users);
1026		}
1027	}
1028	mutex_unlock(&teedev->mutex);
1029}
1030
1031bool tee_device_get(struct tee_device *teedev)
1032{
1033	mutex_lock(&teedev->mutex);
1034	if (!teedev->desc) {
1035		mutex_unlock(&teedev->mutex);
1036		return false;
1037	}
1038	teedev->num_users++;
1039	mutex_unlock(&teedev->mutex);
1040	return true;
1041}
1042
1043/**
1044 * tee_device_unregister() - Removes a TEE device
1045 * @teedev:	Device to unregister
1046 *
1047 * This function should be called to remove the @teedev even if
1048 * tee_device_register() hasn't been called yet. Does nothing if
1049 * @teedev is NULL.
1050 */
1051void tee_device_unregister(struct tee_device *teedev)
1052{
1053	if (!teedev)
1054		return;
1055
1056	if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED)
1057		cdev_device_del(&teedev->cdev, &teedev->dev);
1058
1059	tee_device_put(teedev);
1060	wait_for_completion(&teedev->c_no_users);
1061
1062	/*
1063	 * No need to take a mutex any longer now since teedev->desc was
1064	 * set to NULL before teedev->c_no_users was completed.
1065	 */
1066
1067	teedev->pool = NULL;
1068
1069	put_device(&teedev->dev);
1070}
1071EXPORT_SYMBOL_GPL(tee_device_unregister);
1072
1073/**
1074 * tee_get_drvdata() - Return driver_data pointer
1075 * @teedev:	Device containing the driver_data pointer
1076 * @returns the driver_data pointer supplied to tee_device_alloc().
1077 */
1078void *tee_get_drvdata(struct tee_device *teedev)
1079{
1080	return dev_get_drvdata(&teedev->dev);
1081}
1082EXPORT_SYMBOL_GPL(tee_get_drvdata);
1083
1084struct match_dev_data {
1085	struct tee_ioctl_version_data *vers;
1086	const void *data;
1087	int (*match)(struct tee_ioctl_version_data *, const void *);
1088};
1089
1090static int match_dev(struct device *dev, const void *data)
1091{
1092	const struct match_dev_data *match_data = data;
1093	struct tee_device *teedev = container_of(dev, struct tee_device, dev);
1094
1095	teedev->desc->ops->get_version(teedev, match_data->vers);
1096	return match_data->match(match_data->vers, match_data->data);
1097}
1098
1099struct tee_context *
1100tee_client_open_context(struct tee_context *start,
1101			int (*match)(struct tee_ioctl_version_data *,
1102				     const void *),
1103			const void *data, struct tee_ioctl_version_data *vers)
1104{
1105	struct device *dev = NULL;
1106	struct device *put_dev = NULL;
1107	struct tee_context *ctx = NULL;
1108	struct tee_ioctl_version_data v;
1109	struct match_dev_data match_data = { vers ? vers : &v, data, match };
1110
1111	if (start)
1112		dev = &start->teedev->dev;
1113
1114	do {
1115		dev = class_find_device(tee_class, dev, &match_data, match_dev);
1116		if (!dev) {
1117			ctx = ERR_PTR(-ENOENT);
1118			break;
1119		}
1120
1121		put_device(put_dev);
1122		put_dev = dev;
1123
1124		ctx = teedev_open(container_of(dev, struct tee_device, dev));
1125	} while (IS_ERR(ctx) && PTR_ERR(ctx) != -ENOMEM);
1126
1127	put_device(put_dev);
1128	/*
1129	 * Default behaviour for in kernel client is to not wait for
1130	 * tee-supplicant if not present for any requests in this context.
1131	 * Also this flag could be configured again before call to
1132	 * tee_client_open_session() if any in kernel client requires
1133	 * different behaviour.
1134	 */
1135	if (!IS_ERR(ctx))
1136		ctx->supp_nowait = true;
1137
1138	return ctx;
1139}
1140EXPORT_SYMBOL_GPL(tee_client_open_context);
1141
1142void tee_client_close_context(struct tee_context *ctx)
1143{
1144	teedev_close_context(ctx);
1145}
1146EXPORT_SYMBOL_GPL(tee_client_close_context);
1147
1148void tee_client_get_version(struct tee_context *ctx,
1149			    struct tee_ioctl_version_data *vers)
1150{
1151	ctx->teedev->desc->ops->get_version(ctx->teedev, vers);
1152}
1153EXPORT_SYMBOL_GPL(tee_client_get_version);
1154
1155int tee_client_open_session(struct tee_context *ctx,
1156			    struct tee_ioctl_open_session_arg *arg,
1157			    struct tee_param *param)
1158{
1159	if (!ctx->teedev->desc->ops->open_session)
1160		return -EINVAL;
1161	return ctx->teedev->desc->ops->open_session(ctx, arg, param);
1162}
1163EXPORT_SYMBOL_GPL(tee_client_open_session);
1164
1165int tee_client_close_session(struct tee_context *ctx, u32 session)
1166{
1167	if (!ctx->teedev->desc->ops->close_session)
1168		return -EINVAL;
1169	return ctx->teedev->desc->ops->close_session(ctx, session);
1170}
1171EXPORT_SYMBOL_GPL(tee_client_close_session);
1172
1173int tee_client_invoke_func(struct tee_context *ctx,
1174			   struct tee_ioctl_invoke_arg *arg,
1175			   struct tee_param *param)
1176{
1177	if (!ctx->teedev->desc->ops->invoke_func)
1178		return -EINVAL;
1179	return ctx->teedev->desc->ops->invoke_func(ctx, arg, param);
1180}
1181EXPORT_SYMBOL_GPL(tee_client_invoke_func);
1182
1183int tee_client_cancel_req(struct tee_context *ctx,
1184			  struct tee_ioctl_cancel_arg *arg)
1185{
1186	if (!ctx->teedev->desc->ops->cancel_req)
1187		return -EINVAL;
1188	return ctx->teedev->desc->ops->cancel_req(ctx, arg->cancel_id,
1189						  arg->session);
1190}
1191
1192static int tee_client_device_match(struct device *dev,
1193				   struct device_driver *drv)
1194{
1195	const struct tee_client_device_id *id_table;
1196	struct tee_client_device *tee_device;
1197
1198	id_table = to_tee_client_driver(drv)->id_table;
1199	tee_device = to_tee_client_device(dev);
1200
1201	while (!uuid_is_null(&id_table->uuid)) {
1202		if (uuid_equal(&tee_device->id.uuid, &id_table->uuid))
1203			return 1;
1204		id_table++;
1205	}
1206
1207	return 0;
1208}
1209
1210static int tee_client_device_uevent(const struct device *dev,
1211				    struct kobj_uevent_env *env)
1212{
1213	uuid_t *dev_id = &to_tee_client_device(dev)->id.uuid;
1214
1215	return add_uevent_var(env, "MODALIAS=tee:%pUb", dev_id);
1216}
1217
1218struct bus_type tee_bus_type = {
1219	.name		= "tee",
1220	.match		= tee_client_device_match,
1221	.uevent		= tee_client_device_uevent,
1222};
1223EXPORT_SYMBOL_GPL(tee_bus_type);
1224
1225static int __init tee_init(void)
1226{
1227	int rc;
1228
1229	tee_class = class_create("tee");
1230	if (IS_ERR(tee_class)) {
1231		pr_err("couldn't create class\n");
1232		return PTR_ERR(tee_class);
1233	}
1234
1235	rc = alloc_chrdev_region(&tee_devt, 0, TEE_NUM_DEVICES, "tee");
1236	if (rc) {
1237		pr_err("failed to allocate char dev region\n");
1238		goto out_unreg_class;
1239	}
1240
1241	rc = bus_register(&tee_bus_type);
1242	if (rc) {
1243		pr_err("failed to register tee bus\n");
1244		goto out_unreg_chrdev;
1245	}
1246
1247	return 0;
1248
1249out_unreg_chrdev:
1250	unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1251out_unreg_class:
1252	class_destroy(tee_class);
1253	tee_class = NULL;
1254
1255	return rc;
1256}
1257
1258static void __exit tee_exit(void)
1259{
1260	bus_unregister(&tee_bus_type);
1261	unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1262	class_destroy(tee_class);
1263	tee_class = NULL;
1264}
1265
1266subsys_initcall(tee_init);
1267module_exit(tee_exit);
1268
1269MODULE_AUTHOR("Linaro");
1270MODULE_DESCRIPTION("TEE Driver");
1271MODULE_VERSION("1.0");
1272MODULE_LICENSE("GPL v2");
1273