1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (c) 2015-2022 Linaro Limited
4 */
5
6#ifndef __TEE_DRV_H
7#define __TEE_DRV_H
8
9#include <linux/device.h>
10#include <linux/idr.h>
11#include <linux/kref.h>
12#include <linux/list.h>
13#include <linux/mod_devicetable.h>
14#include <linux/tee.h>
15#include <linux/types.h>
16#include <linux/uuid.h>
17
18/*
19 * The file describes the API provided by the generic TEE driver to the
20 * specific TEE driver.
21 */
22
23#define TEE_SHM_DYNAMIC		BIT(0)  /* Dynamic shared memory registered */
24					/* in secure world */
25#define TEE_SHM_USER_MAPPED	BIT(1)  /* Memory mapped in user space */
26#define TEE_SHM_POOL		BIT(2)  /* Memory allocated from pool */
27#define TEE_SHM_PRIV		BIT(3)  /* Memory private to TEE driver */
28
29struct device;
30struct tee_device;
31struct tee_shm;
32struct tee_shm_pool;
33
34/**
35 * struct tee_context - driver specific context on file pointer data
36 * @teedev:	pointer to this drivers struct tee_device
37 * @list_shm:	List of shared memory object owned by this context
38 * @data:	driver specific context data, managed by the driver
39 * @refcount:	reference counter for this structure
40 * @releasing:  flag that indicates if context is being released right now.
41 *		It is needed to break circular dependency on context during
42 *              shared memory release.
43 * @supp_nowait: flag that indicates that requests in this context should not
44 *              wait for tee-supplicant daemon to be started if not present
45 *              and just return with an error code. It is needed for requests
46 *              that arises from TEE based kernel drivers that should be
47 *              non-blocking in nature.
48 * @cap_memref_null: flag indicating if the TEE Client support shared
49 *                   memory buffer with a NULL pointer.
50 */
51struct tee_context {
52	struct tee_device *teedev;
53	void *data;
54	struct kref refcount;
55	bool releasing;
56	bool supp_nowait;
57	bool cap_memref_null;
58};
59
60struct tee_param_memref {
61	size_t shm_offs;
62	size_t size;
63	struct tee_shm *shm;
64};
65
66struct tee_param_value {
67	u64 a;
68	u64 b;
69	u64 c;
70};
71
72struct tee_param {
73	u64 attr;
74	union {
75		struct tee_param_memref memref;
76		struct tee_param_value value;
77	} u;
78};
79
80/**
81 * struct tee_driver_ops - driver operations vtable
82 * @get_version:	returns version of driver
83 * @open:		called when the device file is opened
84 * @release:		release this open file
85 * @open_session:	open a new session
86 * @close_session:	close a session
87 * @system_session:	declare session as a system session
88 * @invoke_func:	invoke a trusted function
89 * @cancel_req:		request cancel of an ongoing invoke or open
90 * @supp_recv:		called for supplicant to get a command
91 * @supp_send:		called for supplicant to send a response
92 * @shm_register:	register shared memory buffer in TEE
93 * @shm_unregister:	unregister shared memory buffer in TEE
94 */
95struct tee_driver_ops {
96	void (*get_version)(struct tee_device *teedev,
97			    struct tee_ioctl_version_data *vers);
98	int (*open)(struct tee_context *ctx);
99	void (*release)(struct tee_context *ctx);
100	int (*open_session)(struct tee_context *ctx,
101			    struct tee_ioctl_open_session_arg *arg,
102			    struct tee_param *param);
103	int (*close_session)(struct tee_context *ctx, u32 session);
104	int (*system_session)(struct tee_context *ctx, u32 session);
105	int (*invoke_func)(struct tee_context *ctx,
106			   struct tee_ioctl_invoke_arg *arg,
107			   struct tee_param *param);
108	int (*cancel_req)(struct tee_context *ctx, u32 cancel_id, u32 session);
109	int (*supp_recv)(struct tee_context *ctx, u32 *func, u32 *num_params,
110			 struct tee_param *param);
111	int (*supp_send)(struct tee_context *ctx, u32 ret, u32 num_params,
112			 struct tee_param *param);
113	int (*shm_register)(struct tee_context *ctx, struct tee_shm *shm,
114			    struct page **pages, size_t num_pages,
115			    unsigned long start);
116	int (*shm_unregister)(struct tee_context *ctx, struct tee_shm *shm);
117};
118
119/**
120 * struct tee_desc - Describes the TEE driver to the subsystem
121 * @name:	name of driver
122 * @ops:	driver operations vtable
123 * @owner:	module providing the driver
124 * @flags:	Extra properties of driver, defined by TEE_DESC_* below
125 */
126#define TEE_DESC_PRIVILEGED	0x1
127struct tee_desc {
128	const char *name;
129	const struct tee_driver_ops *ops;
130	struct module *owner;
131	u32 flags;
132};
133
134/**
135 * tee_device_alloc() - Allocate a new struct tee_device instance
136 * @teedesc:	Descriptor for this driver
137 * @dev:	Parent device for this device
138 * @pool:	Shared memory pool, NULL if not used
139 * @driver_data: Private driver data for this device
140 *
141 * Allocates a new struct tee_device instance. The device is
142 * removed by tee_device_unregister().
143 *
144 * @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
145 */
146struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
147				    struct device *dev,
148				    struct tee_shm_pool *pool,
149				    void *driver_data);
150
151/**
152 * tee_device_register() - Registers a TEE device
153 * @teedev:	Device to register
154 *
155 * tee_device_unregister() need to be called to remove the @teedev if
156 * this function fails.
157 *
158 * @returns < 0 on failure
159 */
160int tee_device_register(struct tee_device *teedev);
161
162/**
163 * tee_device_unregister() - Removes a TEE device
164 * @teedev:	Device to unregister
165 *
166 * This function should be called to remove the @teedev even if
167 * tee_device_register() hasn't been called yet. Does nothing if
168 * @teedev is NULL.
169 */
170void tee_device_unregister(struct tee_device *teedev);
171
172/**
173 * tee_session_calc_client_uuid() - Calculates client UUID for session
174 * @uuid:		Resulting UUID
175 * @connection_method:	Connection method for session (TEE_IOCTL_LOGIN_*)
176 * @connectuon_data:	Connection data for opening session
177 *
178 * Based on connection method calculates UUIDv5 based client UUID.
179 *
180 * For group based logins verifies that calling process has specified
181 * credentials.
182 *
183 * @return < 0 on failure
184 */
185int tee_session_calc_client_uuid(uuid_t *uuid, u32 connection_method,
186				 const u8 connection_data[TEE_IOCTL_UUID_LEN]);
187
188/**
189 * struct tee_shm - shared memory object
190 * @ctx:	context using the object
191 * @paddr:	physical address of the shared memory
192 * @kaddr:	virtual address of the shared memory
193 * @size:	size of shared memory
194 * @offset:	offset of buffer in user space
195 * @pages:	locked pages from userspace
196 * @num_pages:	number of locked pages
197 * @refcount:	reference counter
198 * @flags:	defined by TEE_SHM_* in tee_drv.h
199 * @id:		unique id of a shared memory object on this device, shared
200 *		with user space
201 * @sec_world_id:
202 *		secure world assigned id of this shared memory object, not
203 *		used by all drivers
204 *
205 * This pool is only supposed to be accessed directly from the TEE
206 * subsystem and from drivers that implements their own shm pool manager.
207 */
208struct tee_shm {
209	struct tee_context *ctx;
210	phys_addr_t paddr;
211	void *kaddr;
212	size_t size;
213	unsigned int offset;
214	struct page **pages;
215	size_t num_pages;
216	refcount_t refcount;
217	u32 flags;
218	int id;
219	u64 sec_world_id;
220};
221
222/**
223 * struct tee_shm_pool - shared memory pool
224 * @ops:		operations
225 * @private_data:	private data for the shared memory manager
226 */
227struct tee_shm_pool {
228	const struct tee_shm_pool_ops *ops;
229	void *private_data;
230};
231
232/**
233 * struct tee_shm_pool_ops - shared memory pool operations
234 * @alloc:		called when allocating shared memory
235 * @free:		called when freeing shared memory
236 * @destroy_pool:	called when destroying the pool
237 */
238struct tee_shm_pool_ops {
239	int (*alloc)(struct tee_shm_pool *pool, struct tee_shm *shm,
240		     size_t size, size_t align);
241	void (*free)(struct tee_shm_pool *pool, struct tee_shm *shm);
242	void (*destroy_pool)(struct tee_shm_pool *pool);
243};
244
245/*
246 * tee_shm_pool_alloc_res_mem() - Create a shm manager for reserved memory
247 * @vaddr:	Virtual address of start of pool
248 * @paddr:	Physical address of start of pool
249 * @size:	Size in bytes of the pool
250 *
251 * @returns pointer to a 'struct tee_shm_pool' or an ERR_PTR on failure.
252 */
253struct tee_shm_pool *tee_shm_pool_alloc_res_mem(unsigned long vaddr,
254						phys_addr_t paddr, size_t size,
255						int min_alloc_order);
256
257/**
258 * tee_shm_pool_free() - Free a shared memory pool
259 * @pool:	The shared memory pool to free
260 *
261 * The must be no remaining shared memory allocated from this pool when
262 * this function is called.
263 */
264static inline void tee_shm_pool_free(struct tee_shm_pool *pool)
265{
266	pool->ops->destroy_pool(pool);
267}
268
269/**
270 * tee_get_drvdata() - Return driver_data pointer
271 * @returns the driver_data pointer supplied to tee_register().
272 */
273void *tee_get_drvdata(struct tee_device *teedev);
274
275struct tee_shm *tee_shm_alloc_priv_buf(struct tee_context *ctx, size_t size);
276struct tee_shm *tee_shm_alloc_kernel_buf(struct tee_context *ctx, size_t size);
277
278struct tee_shm *tee_shm_register_kernel_buf(struct tee_context *ctx,
279					    void *addr, size_t length);
280
281/**
282 * tee_shm_is_dynamic() - Check if shared memory object is of the dynamic kind
283 * @shm:	Shared memory handle
284 * @returns true if object is dynamic shared memory
285 */
286static inline bool tee_shm_is_dynamic(struct tee_shm *shm)
287{
288	return shm && (shm->flags & TEE_SHM_DYNAMIC);
289}
290
291/**
292 * tee_shm_free() - Free shared memory
293 * @shm:	Handle to shared memory to free
294 */
295void tee_shm_free(struct tee_shm *shm);
296
297/**
298 * tee_shm_put() - Decrease reference count on a shared memory handle
299 * @shm:	Shared memory handle
300 */
301void tee_shm_put(struct tee_shm *shm);
302
303/**
304 * tee_shm_get_va() - Get virtual address of a shared memory plus an offset
305 * @shm:	Shared memory handle
306 * @offs:	Offset from start of this shared memory
307 * @returns virtual address of the shared memory + offs if offs is within
308 *	the bounds of this shared memory, else an ERR_PTR
309 */
310void *tee_shm_get_va(struct tee_shm *shm, size_t offs);
311
312/**
313 * tee_shm_get_pa() - Get physical address of a shared memory plus an offset
314 * @shm:	Shared memory handle
315 * @offs:	Offset from start of this shared memory
316 * @pa:		Physical address to return
317 * @returns 0 if offs is within the bounds of this shared memory, else an
318 *	error code.
319 */
320int tee_shm_get_pa(struct tee_shm *shm, size_t offs, phys_addr_t *pa);
321
322/**
323 * tee_shm_get_size() - Get size of shared memory buffer
324 * @shm:	Shared memory handle
325 * @returns size of shared memory
326 */
327static inline size_t tee_shm_get_size(struct tee_shm *shm)
328{
329	return shm->size;
330}
331
332/**
333 * tee_shm_get_pages() - Get list of pages that hold shared buffer
334 * @shm:	Shared memory handle
335 * @num_pages:	Number of pages will be stored there
336 * @returns pointer to pages array
337 */
338static inline struct page **tee_shm_get_pages(struct tee_shm *shm,
339					      size_t *num_pages)
340{
341	*num_pages = shm->num_pages;
342	return shm->pages;
343}
344
345/**
346 * tee_shm_get_page_offset() - Get shared buffer offset from page start
347 * @shm:	Shared memory handle
348 * @returns page offset of shared buffer
349 */
350static inline size_t tee_shm_get_page_offset(struct tee_shm *shm)
351{
352	return shm->offset;
353}
354
355/**
356 * tee_shm_get_id() - Get id of a shared memory object
357 * @shm:	Shared memory handle
358 * @returns id
359 */
360static inline int tee_shm_get_id(struct tee_shm *shm)
361{
362	return shm->id;
363}
364
365/**
366 * tee_shm_get_from_id() - Find shared memory object and increase reference
367 * count
368 * @ctx:	Context owning the shared memory
369 * @id:		Id of shared memory object
370 * @returns a pointer to 'struct tee_shm' on success or an ERR_PTR on failure
371 */
372struct tee_shm *tee_shm_get_from_id(struct tee_context *ctx, int id);
373
374/**
375 * tee_client_open_context() - Open a TEE context
376 * @start:	if not NULL, continue search after this context
377 * @match:	function to check TEE device
378 * @data:	data for match function
379 * @vers:	if not NULL, version data of TEE device of the context returned
380 *
381 * This function does an operation similar to open("/dev/teeX") in user space.
382 * A returned context must be released with tee_client_close_context().
383 *
384 * Returns a TEE context of the first TEE device matched by the match()
385 * callback or an ERR_PTR.
386 */
387struct tee_context *
388tee_client_open_context(struct tee_context *start,
389			int (*match)(struct tee_ioctl_version_data *,
390				     const void *),
391			const void *data, struct tee_ioctl_version_data *vers);
392
393/**
394 * tee_client_close_context() - Close a TEE context
395 * @ctx:	TEE context to close
396 *
397 * Note that all sessions previously opened with this context will be
398 * closed when this function is called.
399 */
400void tee_client_close_context(struct tee_context *ctx);
401
402/**
403 * tee_client_get_version() - Query version of TEE
404 * @ctx:	TEE context to TEE to query
405 * @vers:	Pointer to version data
406 */
407void tee_client_get_version(struct tee_context *ctx,
408			    struct tee_ioctl_version_data *vers);
409
410/**
411 * tee_client_open_session() - Open a session to a Trusted Application
412 * @ctx:	TEE context
413 * @arg:	Open session arguments, see description of
414 *		struct tee_ioctl_open_session_arg
415 * @param:	Parameters passed to the Trusted Application
416 *
417 * Returns < 0 on error else see @arg->ret for result. If @arg->ret
418 * is TEEC_SUCCESS the session identifier is available in @arg->session.
419 */
420int tee_client_open_session(struct tee_context *ctx,
421			    struct tee_ioctl_open_session_arg *arg,
422			    struct tee_param *param);
423
424/**
425 * tee_client_close_session() - Close a session to a Trusted Application
426 * @ctx:	TEE Context
427 * @session:	Session id
428 *
429 * Return < 0 on error else 0, regardless the session will not be
430 * valid after this function has returned.
431 */
432int tee_client_close_session(struct tee_context *ctx, u32 session);
433
434/**
435 * tee_client_system_session() - Declare session as a system session
436 * @ctx:	TEE Context
437 * @session:	Session id
438 *
439 * This function requests TEE to provision an entry context ready to use for
440 * that session only. The provisioned entry context is used for command
441 * invocation and session closure, not for command cancelling requests.
442 * TEE releases the provisioned context upon session closure.
443 *
444 * Return < 0 on error else 0 if an entry context has been provisioned.
445 */
446int tee_client_system_session(struct tee_context *ctx, u32 session);
447
448/**
449 * tee_client_invoke_func() - Invoke a function in a Trusted Application
450 * @ctx:	TEE Context
451 * @arg:	Invoke arguments, see description of
452 *		struct tee_ioctl_invoke_arg
453 * @param:	Parameters passed to the Trusted Application
454 *
455 * Returns < 0 on error else see @arg->ret for result.
456 */
457int tee_client_invoke_func(struct tee_context *ctx,
458			   struct tee_ioctl_invoke_arg *arg,
459			   struct tee_param *param);
460
461/**
462 * tee_client_cancel_req() - Request cancellation of the previous open-session
463 * or invoke-command operations in a Trusted Application
464 * @ctx:       TEE Context
465 * @arg:       Cancellation arguments, see description of
466 *             struct tee_ioctl_cancel_arg
467 *
468 * Returns < 0 on error else 0 if the cancellation was successfully requested.
469 */
470int tee_client_cancel_req(struct tee_context *ctx,
471			  struct tee_ioctl_cancel_arg *arg);
472
473static inline bool tee_param_is_memref(struct tee_param *param)
474{
475	switch (param->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
476	case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
477	case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
478	case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
479		return true;
480	default:
481		return false;
482	}
483}
484
485extern const struct bus_type tee_bus_type;
486
487/**
488 * struct tee_client_device - tee based device
489 * @id:			device identifier
490 * @dev:		device structure
491 */
492struct tee_client_device {
493	struct tee_client_device_id id;
494	struct device dev;
495};
496
497#define to_tee_client_device(d) container_of(d, struct tee_client_device, dev)
498
499/**
500 * struct tee_client_driver - tee client driver
501 * @id_table:		device id table supported by this driver
502 * @driver:		driver structure
503 */
504struct tee_client_driver {
505	const struct tee_client_device_id *id_table;
506	struct device_driver driver;
507};
508
509#define to_tee_client_driver(d) \
510		container_of(d, struct tee_client_driver, driver)
511
512/**
513 * teedev_open() - Open a struct tee_device
514 * @teedev:	Device to open
515 *
516 * @return a pointer to struct tee_context on success or an ERR_PTR on failure.
517 */
518struct tee_context *teedev_open(struct tee_device *teedev);
519
520/**
521 * teedev_close_context() - closes a struct tee_context
522 * @ctx:	The struct tee_context to close
523 */
524void teedev_close_context(struct tee_context *ctx);
525
526#endif /*__TEE_DRV_H*/
527