xref: /linux/drivers/tee/optee/rpc.c (revision 69050f8d6d075dc01af7a5f2f550a8067510366f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2015-2021, Linaro Limited
4  */
5 
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7 
8 #include <linux/delay.h>
9 #include <linux/i2c.h>
10 #include <linux/rpmb.h>
11 #include <linux/slab.h>
12 #include <linux/tee_core.h>
13 #include "optee_private.h"
14 #include "optee_rpc_cmd.h"
15 
16 static void handle_rpc_func_cmd_get_time(struct optee_msg_arg *arg)
17 {
18 	struct timespec64 ts;
19 
20 	if (arg->num_params != 1)
21 		goto bad;
22 	if ((arg->params[0].attr & OPTEE_MSG_ATTR_TYPE_MASK) !=
23 			OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT)
24 		goto bad;
25 
26 	ktime_get_real_ts64(&ts);
27 	arg->params[0].u.value.a = ts.tv_sec;
28 	arg->params[0].u.value.b = ts.tv_nsec;
29 
30 	arg->ret = TEEC_SUCCESS;
31 	return;
32 bad:
33 	arg->ret = TEEC_ERROR_BAD_PARAMETERS;
34 }
35 
36 #if IS_REACHABLE(CONFIG_I2C)
37 static void handle_rpc_func_cmd_i2c_transfer(struct tee_context *ctx,
38 					     struct optee_msg_arg *arg)
39 {
40 	struct optee *optee = tee_get_drvdata(ctx->teedev);
41 	struct tee_param *params;
42 	struct i2c_adapter *adapter;
43 	struct i2c_msg msg = { };
44 	size_t i;
45 	int ret = -EOPNOTSUPP;
46 	static const u8 attr[] = {
47 		TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT,
48 		TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT,
49 		TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT,
50 		TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT,
51 	};
52 
53 	if (arg->num_params != ARRAY_SIZE(attr)) {
54 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
55 		return;
56 	}
57 
58 	params = kmalloc_objs(struct tee_param, arg->num_params, GFP_KERNEL);
59 	if (!params) {
60 		arg->ret = TEEC_ERROR_OUT_OF_MEMORY;
61 		return;
62 	}
63 
64 	if (optee->ops->from_msg_param(optee, params, arg->num_params,
65 				       arg->params))
66 		goto bad;
67 
68 	for (i = 0; i < arg->num_params; i++) {
69 		if (params[i].attr != attr[i])
70 			goto bad;
71 	}
72 
73 	adapter = i2c_get_adapter(params[0].u.value.b);
74 	if (!adapter)
75 		goto bad;
76 
77 	if (params[1].u.value.a & OPTEE_RPC_I2C_FLAGS_TEN_BIT) {
78 		if (!i2c_check_functionality(adapter,
79 					     I2C_FUNC_10BIT_ADDR)) {
80 			i2c_put_adapter(adapter);
81 			goto bad;
82 		}
83 
84 		msg.flags = I2C_M_TEN;
85 	}
86 
87 	msg.addr = params[0].u.value.c;
88 	msg.buf  = params[2].u.memref.shm->kaddr;
89 	msg.len  = params[2].u.memref.size;
90 
91 	switch (params[0].u.value.a) {
92 	case OPTEE_RPC_I2C_TRANSFER_RD:
93 		msg.flags |= I2C_M_RD;
94 		break;
95 	case OPTEE_RPC_I2C_TRANSFER_WR:
96 		break;
97 	default:
98 		i2c_put_adapter(adapter);
99 		goto bad;
100 	}
101 
102 	ret = i2c_transfer(adapter, &msg, 1);
103 
104 	if (ret < 0) {
105 		arg->ret = TEEC_ERROR_COMMUNICATION;
106 	} else {
107 		params[3].u.value.a = msg.len;
108 		if (optee->ops->to_msg_param(optee, arg->params,
109 					     arg->num_params, params))
110 			arg->ret = TEEC_ERROR_BAD_PARAMETERS;
111 		else
112 			arg->ret = TEEC_SUCCESS;
113 	}
114 
115 	i2c_put_adapter(adapter);
116 	kfree(params);
117 	return;
118 bad:
119 	kfree(params);
120 	arg->ret = TEEC_ERROR_BAD_PARAMETERS;
121 }
122 #else
123 static void handle_rpc_func_cmd_i2c_transfer(struct tee_context *ctx,
124 					     struct optee_msg_arg *arg)
125 {
126 	arg->ret = TEEC_ERROR_NOT_SUPPORTED;
127 }
128 #endif
129 
130 static void handle_rpc_func_cmd_wq(struct optee *optee,
131 				   struct optee_msg_arg *arg)
132 {
133 	int rc = 0;
134 
135 	if (arg->num_params != 1)
136 		goto bad;
137 
138 	if ((arg->params[0].attr & OPTEE_MSG_ATTR_TYPE_MASK) !=
139 			OPTEE_MSG_ATTR_TYPE_VALUE_INPUT)
140 		goto bad;
141 
142 	switch (arg->params[0].u.value.a) {
143 	case OPTEE_RPC_NOTIFICATION_WAIT:
144 		rc = optee_notif_wait(optee, arg->params[0].u.value.b, arg->params[0].u.value.c);
145 		if (rc)
146 			goto bad;
147 		break;
148 	case OPTEE_RPC_NOTIFICATION_SEND:
149 		if (optee_notif_send(optee, arg->params[0].u.value.b))
150 			goto bad;
151 		break;
152 	default:
153 		goto bad;
154 	}
155 
156 	arg->ret = TEEC_SUCCESS;
157 	return;
158 bad:
159 	if (rc == -ETIMEDOUT)
160 		arg->ret = TEE_ERROR_TIMEOUT;
161 	else
162 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
163 }
164 
165 static void handle_rpc_func_cmd_wait(struct optee_msg_arg *arg)
166 {
167 	u32 msec_to_wait;
168 
169 	if (arg->num_params != 1)
170 		goto bad;
171 
172 	if ((arg->params[0].attr & OPTEE_MSG_ATTR_TYPE_MASK) !=
173 			OPTEE_MSG_ATTR_TYPE_VALUE_INPUT)
174 		goto bad;
175 
176 	msec_to_wait = arg->params[0].u.value.a;
177 
178 	/* Go to interruptible sleep */
179 	msleep_interruptible(msec_to_wait);
180 
181 	arg->ret = TEEC_SUCCESS;
182 	return;
183 bad:
184 	arg->ret = TEEC_ERROR_BAD_PARAMETERS;
185 }
186 
187 static void handle_rpc_supp_cmd(struct tee_context *ctx, struct optee *optee,
188 				struct optee_msg_arg *arg)
189 {
190 	struct tee_param *params;
191 
192 	arg->ret_origin = TEEC_ORIGIN_COMMS;
193 
194 	params = kmalloc_objs(struct tee_param, arg->num_params, GFP_KERNEL);
195 	if (!params) {
196 		arg->ret = TEEC_ERROR_OUT_OF_MEMORY;
197 		return;
198 	}
199 
200 	if (optee->ops->from_msg_param(optee, params, arg->num_params,
201 				       arg->params)) {
202 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
203 		goto out;
204 	}
205 
206 	arg->ret = optee_supp_thrd_req(ctx, arg->cmd, arg->num_params, params);
207 
208 	if (optee->ops->to_msg_param(optee, arg->params, arg->num_params,
209 				     params))
210 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
211 out:
212 	kfree(params);
213 }
214 
215 struct tee_shm *optee_rpc_cmd_alloc_suppl(struct tee_context *ctx, size_t sz)
216 {
217 	u32 ret;
218 	struct tee_param param;
219 	struct optee *optee = tee_get_drvdata(ctx->teedev);
220 	struct tee_shm *shm;
221 
222 	param.attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT;
223 	param.u.value.a = OPTEE_RPC_SHM_TYPE_APPL;
224 	param.u.value.b = sz;
225 	param.u.value.c = 0;
226 
227 	ret = optee_supp_thrd_req(ctx, OPTEE_RPC_CMD_SHM_ALLOC, 1, &param);
228 	if (ret)
229 		return ERR_PTR(-ENOMEM);
230 
231 	mutex_lock(&optee->supp.mutex);
232 	/* Increases count as secure world doesn't have a reference */
233 	shm = tee_shm_get_from_id(optee->supp.ctx, param.u.value.c);
234 	mutex_unlock(&optee->supp.mutex);
235 	return shm;
236 }
237 
238 void optee_rpc_cmd_free_suppl(struct tee_context *ctx, struct tee_shm *shm)
239 {
240 	struct tee_param param;
241 
242 	param.attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT;
243 	param.u.value.a = OPTEE_RPC_SHM_TYPE_APPL;
244 	param.u.value.b = tee_shm_get_id(shm);
245 	param.u.value.c = 0;
246 
247 	/*
248 	 * Match the tee_shm_get_from_id() in optee_rpc_cmd_alloc_suppl()
249 	 * as secure world has released its reference.
250 	 *
251 	 * It's better to do this before sending the request to supplicant
252 	 * as we'd like to let the process doing the initial allocation to
253 	 * do release the last reference too in order to avoid stacking
254 	 * many pending fput() on the client process. This could otherwise
255 	 * happen if secure world does many allocate and free in a single
256 	 * invoke.
257 	 */
258 	tee_shm_put(shm);
259 
260 	optee_supp_thrd_req(ctx, OPTEE_RPC_CMD_SHM_FREE, 1, &param);
261 }
262 
263 static void handle_rpc_func_rpmb_probe_reset(struct tee_context *ctx,
264 					     struct optee *optee,
265 					     struct optee_msg_arg *arg)
266 {
267 	struct tee_param params[1];
268 
269 	if (arg->num_params != ARRAY_SIZE(params) ||
270 	    optee->ops->from_msg_param(optee, params, arg->num_params,
271 				       arg->params) ||
272 	    params[0].attr != TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT) {
273 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
274 		return;
275 	}
276 
277 	params[0].u.value.a = OPTEE_RPC_SHM_TYPE_KERNEL;
278 	params[0].u.value.b = 0;
279 	params[0].u.value.c = 0;
280 	if (optee->ops->to_msg_param(optee, arg->params,
281 				     arg->num_params, params)) {
282 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
283 		return;
284 	}
285 
286 	mutex_lock(&optee->rpmb_dev_mutex);
287 	rpmb_dev_put(optee->rpmb_dev);
288 	optee->rpmb_dev = NULL;
289 	mutex_unlock(&optee->rpmb_dev_mutex);
290 
291 	arg->ret = TEEC_SUCCESS;
292 }
293 
294 static int rpmb_type_to_rpc_type(enum rpmb_type rtype)
295 {
296 	switch (rtype) {
297 	case RPMB_TYPE_EMMC:
298 		return OPTEE_RPC_RPMB_EMMC;
299 	case RPMB_TYPE_UFS:
300 		return OPTEE_RPC_RPMB_UFS;
301 	case RPMB_TYPE_NVME:
302 		return OPTEE_RPC_RPMB_NVME;
303 	default:
304 		return -1;
305 	}
306 }
307 
308 static int rpc_rpmb_match(struct device *dev, const void *data)
309 {
310 	struct rpmb_dev *rdev = to_rpmb_dev(dev);
311 
312 	return rpmb_type_to_rpc_type(rdev->descr.type) >= 0;
313 }
314 
315 static void handle_rpc_func_rpmb_probe_next(struct tee_context *ctx,
316 					    struct optee *optee,
317 					    struct optee_msg_arg *arg)
318 {
319 	struct rpmb_dev *rdev;
320 	struct tee_param params[2];
321 	void *buf;
322 
323 	if (arg->num_params != ARRAY_SIZE(params) ||
324 	    optee->ops->from_msg_param(optee, params, arg->num_params,
325 				       arg->params) ||
326 	    params[0].attr != TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT ||
327 	    params[1].attr != TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT) {
328 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
329 		return;
330 	}
331 	buf = tee_shm_get_va(params[1].u.memref.shm,
332 			     params[1].u.memref.shm_offs);
333 	if (IS_ERR(buf)) {
334 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
335 		return;
336 	}
337 
338 	mutex_lock(&optee->rpmb_dev_mutex);
339 	rdev = rpmb_dev_find_device(NULL, optee->rpmb_dev, rpc_rpmb_match);
340 	rpmb_dev_put(optee->rpmb_dev);
341 	optee->rpmb_dev = rdev;
342 	mutex_unlock(&optee->rpmb_dev_mutex);
343 
344 	if (!rdev) {
345 		arg->ret = TEEC_ERROR_ITEM_NOT_FOUND;
346 		return;
347 	}
348 
349 	if (params[1].u.memref.size < rdev->descr.dev_id_len) {
350 		arg->ret = TEEC_ERROR_SHORT_BUFFER;
351 		return;
352 	}
353 	memcpy(buf, rdev->descr.dev_id, rdev->descr.dev_id_len);
354 	params[1].u.memref.size = rdev->descr.dev_id_len;
355 	params[0].u.value.a = rpmb_type_to_rpc_type(rdev->descr.type);
356 	params[0].u.value.b = rdev->descr.capacity;
357 	params[0].u.value.c = rdev->descr.reliable_wr_count;
358 	if (optee->ops->to_msg_param(optee, arg->params,
359 				     arg->num_params, params)) {
360 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
361 		return;
362 	}
363 
364 	arg->ret = TEEC_SUCCESS;
365 }
366 
367 static void handle_rpc_func_rpmb_frames(struct tee_context *ctx,
368 					struct optee *optee,
369 					struct optee_msg_arg *arg)
370 {
371 	struct tee_param params[2];
372 	struct rpmb_dev *rdev;
373 	void *p0, *p1;
374 
375 	mutex_lock(&optee->rpmb_dev_mutex);
376 	rdev = rpmb_dev_get(optee->rpmb_dev);
377 	mutex_unlock(&optee->rpmb_dev_mutex);
378 	if (!rdev) {
379 		arg->ret = TEEC_ERROR_ITEM_NOT_FOUND;
380 		return;
381 	}
382 
383 	if (arg->num_params != ARRAY_SIZE(params) ||
384 	    optee->ops->from_msg_param(optee, params, arg->num_params,
385 				       arg->params) ||
386 	    params[0].attr != TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT ||
387 	    params[1].attr != TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT) {
388 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
389 		goto out;
390 	}
391 
392 	p0 = tee_shm_get_va(params[0].u.memref.shm,
393 			    params[0].u.memref.shm_offs);
394 	p1 = tee_shm_get_va(params[1].u.memref.shm,
395 			    params[1].u.memref.shm_offs);
396 	if (rpmb_route_frames(rdev, p0, params[0].u.memref.size, p1,
397 			      params[1].u.memref.size)) {
398 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
399 		goto out;
400 	}
401 	if (optee->ops->to_msg_param(optee, arg->params,
402 				     arg->num_params, params)) {
403 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
404 		goto out;
405 	}
406 	arg->ret = TEEC_SUCCESS;
407 out:
408 	rpmb_dev_put(rdev);
409 }
410 
411 void optee_rpc_cmd(struct tee_context *ctx, struct optee *optee,
412 		   struct optee_msg_arg *arg)
413 {
414 	switch (arg->cmd) {
415 	case OPTEE_RPC_CMD_GET_TIME:
416 		handle_rpc_func_cmd_get_time(arg);
417 		break;
418 	case OPTEE_RPC_CMD_NOTIFICATION:
419 		handle_rpc_func_cmd_wq(optee, arg);
420 		break;
421 	case OPTEE_RPC_CMD_SUSPEND:
422 		handle_rpc_func_cmd_wait(arg);
423 		break;
424 	case OPTEE_RPC_CMD_I2C_TRANSFER:
425 		handle_rpc_func_cmd_i2c_transfer(ctx, arg);
426 		break;
427 	/*
428 	 * optee->in_kernel_rpmb_routing true means that OP-TEE supports
429 	 * in-kernel RPMB routing _and_ that the RPMB subsystem is
430 	 * reachable. This is reported to user space with
431 	 * rpmb_routing_model=kernel in sysfs.
432 	 *
433 	 * rpmb_routing_model=kernel is also a promise to user space that
434 	 * RPMB access will not require supplicant support, hence the
435 	 * checks below.
436 	 */
437 	case OPTEE_RPC_CMD_RPMB_PROBE_RESET:
438 		if (optee->in_kernel_rpmb_routing)
439 			handle_rpc_func_rpmb_probe_reset(ctx, optee, arg);
440 		else
441 			handle_rpc_supp_cmd(ctx, optee, arg);
442 		break;
443 	case OPTEE_RPC_CMD_RPMB_PROBE_NEXT:
444 		if (optee->in_kernel_rpmb_routing)
445 			handle_rpc_func_rpmb_probe_next(ctx, optee, arg);
446 		else
447 			handle_rpc_supp_cmd(ctx, optee, arg);
448 		break;
449 	case OPTEE_RPC_CMD_RPMB_FRAMES:
450 		if (optee->in_kernel_rpmb_routing)
451 			handle_rpc_func_rpmb_frames(ctx, optee, arg);
452 		else
453 			handle_rpc_supp_cmd(ctx, optee, arg);
454 		break;
455 	default:
456 		handle_rpc_supp_cmd(ctx, optee, arg);
457 	}
458 }
459 
460 
461