summaryrefslogtreecommitdiffstats
path: root/drivers/tee/optee/device.c
blob: 4b10921276942ed13a43e531b723e746b76dd6fa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2019 Linaro Ltd.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/tee_drv.h>
#include <linux/uuid.h>
#include "optee_private.h"

static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
{
	if (ver->impl_id == TEE_IMPL_ID_OPTEE)
		return 1;
	else
		return 0;
}

static int get_devices(struct tee_context *ctx, u32 session,
		       struct tee_shm *device_shm, u32 *shm_size,
		       u32 func)
{
	int ret = 0;
	struct tee_ioctl_invoke_arg inv_arg;
	struct tee_param param[4];

	memset(&inv_arg, 0, sizeof(inv_arg));
	memset(&param, 0, sizeof(param));

	inv_arg.func = func;
	inv_arg.session = session;
	inv_arg.num_params = 4;

	/* Fill invoke cmd params */
	param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT;
	param[0].u.memref.shm = device_shm;
	param[0].u.memref.size = *shm_size;
	param[0].u.memref.shm_offs = 0;

	ret = tee_client_invoke_func(ctx, &inv_arg, param);
	if ((ret < 0) || ((inv_arg.ret != TEEC_SUCCESS) &&
			  (inv_arg.ret != TEEC_ERROR_SHORT_BUFFER))) {
		pr_err("PTA_CMD_GET_DEVICES invoke function err: %x\n",
		       inv_arg.ret);
		return -EINVAL;
	}

	*shm_size = param[0].u.memref.size;

	return 0;
}

static void optee_release_device(struct device *dev)
{
	struct tee_client_device *optee_device = to_tee_client_device(dev);

	kfree(optee_device);
}

static ssize_t need_supplicant_show(struct device *dev,
				    struct device_attribute *attr,
				    char *buf)
{
	return 0;
}

static DEVICE_ATTR_RO(need_supplicant);

static int optee_register_device(const uuid_t *device_uuid, u32 func)
{
	struct tee_client_device *optee_device = NULL;
	int rc;

	optee_device = kzalloc(sizeof(*optee_device), GFP_KERNEL);
	if (!optee_device)
		return -ENOMEM;

	optee_device->dev.bus = &tee_bus_type;
	optee_device->dev.release = optee_release_device;
	if (dev_set_name(&optee_device->dev, "optee-ta-%pUb", device_uuid)) {
		kfree(optee_device);
		return -ENOMEM;
	}
	uuid_copy(&optee_device->id.uuid, device_uuid);

	rc = device_register(&optee_device->dev);
	if (rc) {
		pr_err("device registration failed, err: %d\n", rc);
		put_device(&optee_device->dev);
	}

	if (func == PTA_CMD_GET_DEVICES_SUPP)
		device_create_file(&optee_device->dev,
				   &dev_attr_need_supplicant);

	return rc;
}

static int __optee_enumerate_devices(u32 func)
{
	const uuid_t pta_uuid =
		UUID_INIT(0x7011a688, 0xddde, 0x4053,
			  0xa5, 0xa9, 0x7b, 0x3c, 0x4d, 0xdf, 0x13, 0xb8);
	struct tee_ioctl_open_session_arg sess_arg;
	struct tee_shm *device_shm = NULL;
	const uuid_t *device_uuid = NULL;
	struct tee_context *ctx = NULL;
	u32 shm_size = 0, idx, num_devices = 0;
	int rc;

	memset(&sess_arg, 0, sizeof(sess_arg));

	/* Open context with OP-TEE driver */
	ctx = tee_client_open_context(NULL, optee_ctx_match, NULL, NULL);
	if (IS_ERR(ctx))
		return -ENODEV;

	/* Open session with device enumeration pseudo TA */
	export_uuid(sess_arg.uuid, &pta_uuid);
	sess_arg.clnt_login = TEE_IOCTL_LOGIN_PUBLIC;
	sess_arg.num_params = 0;

	rc = tee_client_open_session(ctx, &sess_arg, NULL);
	if ((rc < 0) || (sess_arg.ret != TEEC_SUCCESS)) {
		/* Device enumeration pseudo TA not found */
		rc = 0;
		goto out_ctx;
	}

	rc = get_devices(ctx, sess_arg.session, NULL, &shm_size, func);
	if (rc < 0 || !shm_size)
		goto out_sess;

	device_shm = tee_shm_alloc_kernel_buf(ctx, shm_size);
	if (IS_ERR(device_shm)) {
		pr_err("tee_shm_alloc_kernel_buf failed\n");
		rc = PTR_ERR(device_shm);
		goto out_sess;
	}

	rc = get_devices(ctx, sess_arg.session, device_shm, &shm_size, func);
	if (rc < 0)
		goto out_shm;

	device_uuid = tee_shm_get_va(device_shm, 0);
	if (IS_ERR(device_uuid)) {
		pr_err("tee_shm_get_va failed\n");
		rc = PTR_ERR(device_uuid);
		goto out_shm;
	}

	num_devices = shm_size / sizeof(uuid_t);

	for (idx = 0; idx < num_devices; idx++) {
		rc = optee_register_device(&device_uuid[idx], func);
		if (rc)
			goto out_shm;
	}

out_shm:
	tee_shm_free(device_shm);
out_sess:
	tee_client_close_session(ctx, sess_arg.session);
out_ctx:
	tee_client_close_context(ctx);

	return rc;
}

int optee_enumerate_devices(u32 func)
{
	return  __optee_enumerate_devices(func);
}

static int __optee_unregister_device(struct device *dev, void *data)
{
	if (!strncmp(dev_name(dev), "optee-ta", strlen("optee-ta")))
		device_unregister(dev);

	return 0;
}

void optee_unregister_devices(void)
{
	bus_for_each_dev(&tee_bus_type, NULL, NULL,
			 __optee_unregister_device);
}