xref: /openbmc/linux/drivers/tee/optee/rpc.c (revision 9a29f5fc)
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/slab.h>
11 #include <linux/tee_drv.h>
12 #include "optee_private.h"
13 #include "optee_rpc_cmd.h"
14 
15 static void handle_rpc_func_cmd_get_time(struct optee_msg_arg *arg)
16 {
17 	struct timespec64 ts;
18 
19 	if (arg->num_params != 1)
20 		goto bad;
21 	if ((arg->params[0].attr & OPTEE_MSG_ATTR_TYPE_MASK) !=
22 			OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT)
23 		goto bad;
24 
25 	ktime_get_real_ts64(&ts);
26 	arg->params[0].u.value.a = ts.tv_sec;
27 	arg->params[0].u.value.b = ts.tv_nsec;
28 
29 	arg->ret = TEEC_SUCCESS;
30 	return;
31 bad:
32 	arg->ret = TEEC_ERROR_BAD_PARAMETERS;
33 }
34 
35 #if IS_REACHABLE(CONFIG_I2C)
36 static void handle_rpc_func_cmd_i2c_transfer(struct tee_context *ctx,
37 					     struct optee_msg_arg *arg)
38 {
39 	struct optee *optee = tee_get_drvdata(ctx->teedev);
40 	struct tee_param *params;
41 	struct i2c_adapter *adapter;
42 	struct i2c_msg msg = { };
43 	size_t i;
44 	int ret = -EOPNOTSUPP;
45 	u8 attr[] = {
46 		TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT,
47 		TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT,
48 		TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT,
49 		TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT,
50 	};
51 
52 	if (arg->num_params != ARRAY_SIZE(attr)) {
53 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
54 		return;
55 	}
56 
57 	params = kmalloc_array(arg->num_params, sizeof(struct tee_param),
58 			       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 	if (arg->num_params != 1)
134 		goto bad;
135 
136 	if ((arg->params[0].attr & OPTEE_MSG_ATTR_TYPE_MASK) !=
137 			OPTEE_MSG_ATTR_TYPE_VALUE_INPUT)
138 		goto bad;
139 
140 	switch (arg->params[0].u.value.a) {
141 	case OPTEE_RPC_NOTIFICATION_WAIT:
142 		if (optee_notif_wait(optee, arg->params[0].u.value.b))
143 			goto bad;
144 		break;
145 	case OPTEE_RPC_NOTIFICATION_SEND:
146 		if (optee_notif_send(optee, arg->params[0].u.value.b))
147 			goto bad;
148 		break;
149 	default:
150 		goto bad;
151 	}
152 
153 	arg->ret = TEEC_SUCCESS;
154 	return;
155 bad:
156 	arg->ret = TEEC_ERROR_BAD_PARAMETERS;
157 }
158 
159 static void handle_rpc_func_cmd_wait(struct optee_msg_arg *arg)
160 {
161 	u32 msec_to_wait;
162 
163 	if (arg->num_params != 1)
164 		goto bad;
165 
166 	if ((arg->params[0].attr & OPTEE_MSG_ATTR_TYPE_MASK) !=
167 			OPTEE_MSG_ATTR_TYPE_VALUE_INPUT)
168 		goto bad;
169 
170 	msec_to_wait = arg->params[0].u.value.a;
171 
172 	/* Go to interruptible sleep */
173 	msleep_interruptible(msec_to_wait);
174 
175 	arg->ret = TEEC_SUCCESS;
176 	return;
177 bad:
178 	arg->ret = TEEC_ERROR_BAD_PARAMETERS;
179 }
180 
181 static void handle_rpc_supp_cmd(struct tee_context *ctx, struct optee *optee,
182 				struct optee_msg_arg *arg)
183 {
184 	struct tee_param *params;
185 
186 	arg->ret_origin = TEEC_ORIGIN_COMMS;
187 
188 	params = kmalloc_array(arg->num_params, sizeof(struct tee_param),
189 			       GFP_KERNEL);
190 	if (!params) {
191 		arg->ret = TEEC_ERROR_OUT_OF_MEMORY;
192 		return;
193 	}
194 
195 	if (optee->ops->from_msg_param(optee, params, arg->num_params,
196 				       arg->params)) {
197 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
198 		goto out;
199 	}
200 
201 	arg->ret = optee_supp_thrd_req(ctx, arg->cmd, arg->num_params, params);
202 
203 	if (optee->ops->to_msg_param(optee, arg->params, arg->num_params,
204 				     params))
205 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
206 out:
207 	kfree(params);
208 }
209 
210 struct tee_shm *optee_rpc_cmd_alloc_suppl(struct tee_context *ctx, size_t sz)
211 {
212 	u32 ret;
213 	struct tee_param param;
214 	struct optee *optee = tee_get_drvdata(ctx->teedev);
215 	struct tee_shm *shm;
216 
217 	param.attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT;
218 	param.u.value.a = OPTEE_RPC_SHM_TYPE_APPL;
219 	param.u.value.b = sz;
220 	param.u.value.c = 0;
221 
222 	ret = optee_supp_thrd_req(ctx, OPTEE_RPC_CMD_SHM_ALLOC, 1, &param);
223 	if (ret)
224 		return ERR_PTR(-ENOMEM);
225 
226 	mutex_lock(&optee->supp.mutex);
227 	/* Increases count as secure world doesn't have a reference */
228 	shm = tee_shm_get_from_id(optee->supp.ctx, param.u.value.c);
229 	mutex_unlock(&optee->supp.mutex);
230 	return shm;
231 }
232 
233 void optee_rpc_cmd_free_suppl(struct tee_context *ctx, struct tee_shm *shm)
234 {
235 	struct tee_param param;
236 
237 	param.attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT;
238 	param.u.value.a = OPTEE_RPC_SHM_TYPE_APPL;
239 	param.u.value.b = tee_shm_get_id(shm);
240 	param.u.value.c = 0;
241 
242 	/*
243 	 * Match the tee_shm_get_from_id() in cmd_alloc_suppl() as secure
244 	 * world has released its reference.
245 	 *
246 	 * It's better to do this before sending the request to supplicant
247 	 * as we'd like to let the process doing the initial allocation to
248 	 * do release the last reference too in order to avoid stacking
249 	 * many pending fput() on the client process. This could otherwise
250 	 * happen if secure world does many allocate and free in a single
251 	 * invoke.
252 	 */
253 	tee_shm_put(shm);
254 
255 	optee_supp_thrd_req(ctx, OPTEE_RPC_CMD_SHM_FREE, 1, &param);
256 }
257 
258 void optee_rpc_cmd(struct tee_context *ctx, struct optee *optee,
259 		   struct optee_msg_arg *arg)
260 {
261 	switch (arg->cmd) {
262 	case OPTEE_RPC_CMD_GET_TIME:
263 		handle_rpc_func_cmd_get_time(arg);
264 		break;
265 	case OPTEE_RPC_CMD_NOTIFICATION:
266 		handle_rpc_func_cmd_wq(optee, arg);
267 		break;
268 	case OPTEE_RPC_CMD_SUSPEND:
269 		handle_rpc_func_cmd_wait(arg);
270 		break;
271 	case OPTEE_RPC_CMD_I2C_TRANSFER:
272 		handle_rpc_func_cmd_i2c_transfer(ctx, arg);
273 		break;
274 	default:
275 		handle_rpc_supp_cmd(ctx, optee, arg);
276 	}
277 }
278 
279 
280