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