1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright (c) 2024 Linaro Limited
4 */
5
6 #ifndef __TEE_CORE_H
7 #define __TEE_CORE_H
8
9 #include <linux/cdev.h>
10 #include <linux/device.h>
11 #include <linux/idr.h>
12 #include <linux/kref.h>
13 #include <linux/list.h>
14 #include <linux/tee.h>
15 #include <linux/tee_drv.h>
16 #include <linux/types.h>
17 #include <linux/uuid.h>
18
19 /*
20 * The file describes the API provided by the generic TEE driver to the
21 * specific TEE driver.
22 */
23
24 #define TEE_SHM_DYNAMIC BIT(0) /* Dynamic shared memory registered */
25 /* in secure world */
26 #define TEE_SHM_USER_MAPPED BIT(1) /* Memory mapped in user space */
27 #define TEE_SHM_POOL BIT(2) /* Memory allocated from pool */
28 #define TEE_SHM_PRIV BIT(3) /* Memory private to TEE driver */
29
30 #define TEE_DEVICE_FLAG_REGISTERED 0x1
31 #define TEE_MAX_DEV_NAME_LEN 32
32
33 /**
34 * struct tee_device - TEE Device representation
35 * @name: name of device
36 * @desc: description of device
37 * @id: unique id of device
38 * @flags: represented by TEE_DEVICE_FLAG_REGISTERED above
39 * @dev: embedded basic device structure
40 * @cdev: embedded cdev
41 * @num_users: number of active users of this device
42 * @c_no_user: completion used when unregistering the device
43 * @mutex: mutex protecting @num_users and @idr
44 * @idr: register of user space shared memory objects allocated or
45 * registered on this device
46 * @pool: shared memory pool
47 */
48 struct tee_device {
49 char name[TEE_MAX_DEV_NAME_LEN];
50 const struct tee_desc *desc;
51 int id;
52 unsigned int flags;
53
54 struct device dev;
55 struct cdev cdev;
56
57 size_t num_users;
58 struct completion c_no_users;
59 struct mutex mutex; /* protects num_users and idr */
60
61 struct idr idr;
62 struct tee_shm_pool *pool;
63 };
64
65 /**
66 * struct tee_driver_ops - driver operations vtable
67 * @get_version: returns version of driver
68 * @open: called when the device file is opened
69 * @release: release this open file
70 * @open_session: open a new session
71 * @close_session: close a session
72 * @system_session: declare session as a system session
73 * @invoke_func: invoke a trusted function
74 * @cancel_req: request cancel of an ongoing invoke or open
75 * @supp_recv: called for supplicant to get a command
76 * @supp_send: called for supplicant to send a response
77 * @shm_register: register shared memory buffer in TEE
78 * @shm_unregister: unregister shared memory buffer in TEE
79 */
80 struct tee_driver_ops {
81 void (*get_version)(struct tee_device *teedev,
82 struct tee_ioctl_version_data *vers);
83 int (*open)(struct tee_context *ctx);
84 void (*release)(struct tee_context *ctx);
85 int (*open_session)(struct tee_context *ctx,
86 struct tee_ioctl_open_session_arg *arg,
87 struct tee_param *param);
88 int (*close_session)(struct tee_context *ctx, u32 session);
89 int (*system_session)(struct tee_context *ctx, u32 session);
90 int (*invoke_func)(struct tee_context *ctx,
91 struct tee_ioctl_invoke_arg *arg,
92 struct tee_param *param);
93 int (*cancel_req)(struct tee_context *ctx, u32 cancel_id, u32 session);
94 int (*supp_recv)(struct tee_context *ctx, u32 *func, u32 *num_params,
95 struct tee_param *param);
96 int (*supp_send)(struct tee_context *ctx, u32 ret, u32 num_params,
97 struct tee_param *param);
98 int (*shm_register)(struct tee_context *ctx, struct tee_shm *shm,
99 struct page **pages, size_t num_pages,
100 unsigned long start);
101 int (*shm_unregister)(struct tee_context *ctx, struct tee_shm *shm);
102 };
103
104 /**
105 * struct tee_desc - Describes the TEE driver to the subsystem
106 * @name: name of driver
107 * @ops: driver operations vtable
108 * @owner: module providing the driver
109 * @flags: Extra properties of driver, defined by TEE_DESC_* below
110 */
111 #define TEE_DESC_PRIVILEGED 0x1
112 struct tee_desc {
113 const char *name;
114 const struct tee_driver_ops *ops;
115 struct module *owner;
116 u32 flags;
117 };
118
119 /**
120 * tee_device_alloc() - Allocate a new struct tee_device instance
121 * @teedesc: Descriptor for this driver
122 * @dev: Parent device for this device
123 * @pool: Shared memory pool, NULL if not used
124 * @driver_data: Private driver data for this device
125 *
126 * Allocates a new struct tee_device instance. The device is
127 * removed by tee_device_unregister().
128 *
129 * @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
130 */
131 struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
132 struct device *dev,
133 struct tee_shm_pool *pool,
134 void *driver_data);
135
136 /**
137 * tee_device_register() - Registers a TEE device
138 * @teedev: Device to register
139 *
140 * tee_device_unregister() need to be called to remove the @teedev if
141 * this function fails.
142 *
143 * @returns < 0 on failure
144 */
145 int tee_device_register(struct tee_device *teedev);
146
147 /**
148 * tee_device_unregister() - Removes a TEE device
149 * @teedev: Device to unregister
150 *
151 * This function should be called to remove the @teedev even if
152 * tee_device_register() hasn't been called yet. Does nothing if
153 * @teedev is NULL.
154 */
155 void tee_device_unregister(struct tee_device *teedev);
156
157 /**
158 * tee_session_calc_client_uuid() - Calculates client UUID for session
159 * @uuid: Resulting UUID
160 * @connection_method: Connection method for session (TEE_IOCTL_LOGIN_*)
161 * @connectuon_data: Connection data for opening session
162 *
163 * Based on connection method calculates UUIDv5 based client UUID.
164 *
165 * For group based logins verifies that calling process has specified
166 * credentials.
167 *
168 * @return < 0 on failure
169 */
170 int tee_session_calc_client_uuid(uuid_t *uuid, u32 connection_method,
171 const u8 connection_data[TEE_IOCTL_UUID_LEN]);
172
173 /**
174 * struct tee_shm_pool - shared memory pool
175 * @ops: operations
176 * @private_data: private data for the shared memory manager
177 */
178 struct tee_shm_pool {
179 const struct tee_shm_pool_ops *ops;
180 void *private_data;
181 };
182
183 /**
184 * struct tee_shm_pool_ops - shared memory pool operations
185 * @alloc: called when allocating shared memory
186 * @free: called when freeing shared memory
187 * @destroy_pool: called when destroying the pool
188 */
189 struct tee_shm_pool_ops {
190 int (*alloc)(struct tee_shm_pool *pool, struct tee_shm *shm,
191 size_t size, size_t align);
192 void (*free)(struct tee_shm_pool *pool, struct tee_shm *shm);
193 void (*destroy_pool)(struct tee_shm_pool *pool);
194 };
195
196 /*
197 * tee_shm_pool_alloc_res_mem() - Create a shm manager for reserved memory
198 * @vaddr: Virtual address of start of pool
199 * @paddr: Physical address of start of pool
200 * @size: Size in bytes of the pool
201 *
202 * @returns pointer to a 'struct tee_shm_pool' or an ERR_PTR on failure.
203 */
204 struct tee_shm_pool *tee_shm_pool_alloc_res_mem(unsigned long vaddr,
205 phys_addr_t paddr, size_t size,
206 int min_alloc_order);
207
208 /**
209 * tee_shm_pool_free() - Free a shared memory pool
210 * @pool: The shared memory pool to free
211 *
212 * The must be no remaining shared memory allocated from this pool when
213 * this function is called.
214 */
tee_shm_pool_free(struct tee_shm_pool * pool)215 static inline void tee_shm_pool_free(struct tee_shm_pool *pool)
216 {
217 pool->ops->destroy_pool(pool);
218 }
219
220 /**
221 * tee_get_drvdata() - Return driver_data pointer
222 * @returns the driver_data pointer supplied to tee_register().
223 */
224 void *tee_get_drvdata(struct tee_device *teedev);
225
226 /**
227 * tee_shm_alloc_priv_buf() - Allocate shared memory for private use by specific
228 * TEE driver
229 * @ctx: The TEE context for shared memory allocation
230 * @size: Shared memory allocation size
231 * @returns a pointer to 'struct tee_shm' on success or an ERR_PTR on failure
232 */
233 struct tee_shm *tee_shm_alloc_priv_buf(struct tee_context *ctx, size_t size);
234
235 int tee_dyn_shm_alloc_helper(struct tee_shm *shm, size_t size, size_t align,
236 int (*shm_register)(struct tee_context *ctx,
237 struct tee_shm *shm,
238 struct page **pages,
239 size_t num_pages,
240 unsigned long start));
241 void tee_dyn_shm_free_helper(struct tee_shm *shm,
242 int (*shm_unregister)(struct tee_context *ctx,
243 struct tee_shm *shm));
244
245 /**
246 * tee_shm_is_dynamic() - Check if shared memory object is of the dynamic kind
247 * @shm: Shared memory handle
248 * @returns true if object is dynamic shared memory
249 */
tee_shm_is_dynamic(struct tee_shm * shm)250 static inline bool tee_shm_is_dynamic(struct tee_shm *shm)
251 {
252 return shm && (shm->flags & TEE_SHM_DYNAMIC);
253 }
254
255 /**
256 * tee_shm_put() - Decrease reference count on a shared memory handle
257 * @shm: Shared memory handle
258 */
259 void tee_shm_put(struct tee_shm *shm);
260
261 /**
262 * tee_shm_get_id() - Get id of a shared memory object
263 * @shm: Shared memory handle
264 * @returns id
265 */
tee_shm_get_id(struct tee_shm * shm)266 static inline int tee_shm_get_id(struct tee_shm *shm)
267 {
268 return shm->id;
269 }
270
271 /**
272 * tee_shm_get_from_id() - Find shared memory object and increase reference
273 * count
274 * @ctx: Context owning the shared memory
275 * @id: Id of shared memory object
276 * @returns a pointer to 'struct tee_shm' on success or an ERR_PTR on failure
277 */
278 struct tee_shm *tee_shm_get_from_id(struct tee_context *ctx, int id);
279
tee_param_is_memref(struct tee_param * param)280 static inline bool tee_param_is_memref(struct tee_param *param)
281 {
282 switch (param->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
283 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
284 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
285 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
286 return true;
287 default:
288 return false;
289 }
290 }
291
292 /**
293 * teedev_open() - Open a struct tee_device
294 * @teedev: Device to open
295 *
296 * @return a pointer to struct tee_context on success or an ERR_PTR on failure.
297 */
298 struct tee_context *teedev_open(struct tee_device *teedev);
299
300 /**
301 * teedev_close_context() - closes a struct tee_context
302 * @ctx: The struct tee_context to close
303 */
304 void teedev_close_context(struct tee_context *ctx);
305
306 #endif /*__TEE_CORE_H*/
307