1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2019 Linaro Ltd.
4 */
5
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7
8 #include <linux/kernel.h>
9 #include <linux/slab.h>
10 #include <linux/tee_drv.h>
11 #include <linux/uuid.h>
12 #include "optee_private.h"
13
optee_ctx_match(struct tee_ioctl_version_data * ver,const void * data)14 static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
15 {
16 if (ver->impl_id == TEE_IMPL_ID_OPTEE)
17 return 1;
18 else
19 return 0;
20 }
21
get_devices(struct tee_context * ctx,u32 session,struct tee_shm * device_shm,u32 * shm_size,u32 func)22 static int get_devices(struct tee_context *ctx, u32 session,
23 struct tee_shm *device_shm, u32 *shm_size,
24 u32 func)
25 {
26 int ret = 0;
27 struct tee_ioctl_invoke_arg inv_arg;
28 struct tee_param param[4];
29
30 memset(&inv_arg, 0, sizeof(inv_arg));
31 memset(¶m, 0, sizeof(param));
32
33 inv_arg.func = func;
34 inv_arg.session = session;
35 inv_arg.num_params = 4;
36
37 /* Fill invoke cmd params */
38 param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT;
39 param[0].u.memref.shm = device_shm;
40 param[0].u.memref.size = *shm_size;
41 param[0].u.memref.shm_offs = 0;
42
43 ret = tee_client_invoke_func(ctx, &inv_arg, param);
44 if ((ret < 0) || ((inv_arg.ret != TEEC_SUCCESS) &&
45 (inv_arg.ret != TEEC_ERROR_SHORT_BUFFER))) {
46 pr_err("PTA_CMD_GET_DEVICES invoke function err: %x\n",
47 inv_arg.ret);
48 return -EINVAL;
49 }
50
51 *shm_size = param[0].u.memref.size;
52
53 return 0;
54 }
55
optee_release_device(struct device * dev)56 static void optee_release_device(struct device *dev)
57 {
58 struct tee_client_device *optee_device = to_tee_client_device(dev);
59
60 kfree(optee_device);
61 }
62
optee_register_device(const uuid_t * device_uuid)63 static int optee_register_device(const uuid_t *device_uuid)
64 {
65 struct tee_client_device *optee_device = NULL;
66 int rc;
67
68 optee_device = kzalloc(sizeof(*optee_device), GFP_KERNEL);
69 if (!optee_device)
70 return -ENOMEM;
71
72 optee_device->dev.bus = &tee_bus_type;
73 optee_device->dev.release = optee_release_device;
74 if (dev_set_name(&optee_device->dev, "optee-ta-%pUb", device_uuid)) {
75 kfree(optee_device);
76 return -ENOMEM;
77 }
78 uuid_copy(&optee_device->id.uuid, device_uuid);
79
80 rc = device_register(&optee_device->dev);
81 if (rc) {
82 pr_err("device registration failed, err: %d\n", rc);
83 put_device(&optee_device->dev);
84 }
85
86 return rc;
87 }
88
__optee_enumerate_devices(u32 func)89 static int __optee_enumerate_devices(u32 func)
90 {
91 const uuid_t pta_uuid =
92 UUID_INIT(0x7011a688, 0xddde, 0x4053,
93 0xa5, 0xa9, 0x7b, 0x3c, 0x4d, 0xdf, 0x13, 0xb8);
94 struct tee_ioctl_open_session_arg sess_arg;
95 struct tee_shm *device_shm = NULL;
96 const uuid_t *device_uuid = NULL;
97 struct tee_context *ctx = NULL;
98 u32 shm_size = 0, idx, num_devices = 0;
99 int rc;
100
101 memset(&sess_arg, 0, sizeof(sess_arg));
102
103 /* Open context with OP-TEE driver */
104 ctx = tee_client_open_context(NULL, optee_ctx_match, NULL, NULL);
105 if (IS_ERR(ctx))
106 return -ENODEV;
107
108 /* Open session with device enumeration pseudo TA */
109 export_uuid(sess_arg.uuid, &pta_uuid);
110 sess_arg.clnt_login = TEE_IOCTL_LOGIN_PUBLIC;
111 sess_arg.num_params = 0;
112
113 rc = tee_client_open_session(ctx, &sess_arg, NULL);
114 if ((rc < 0) || (sess_arg.ret != TEEC_SUCCESS)) {
115 /* Device enumeration pseudo TA not found */
116 rc = 0;
117 goto out_ctx;
118 }
119
120 rc = get_devices(ctx, sess_arg.session, NULL, &shm_size, func);
121 if (rc < 0 || !shm_size)
122 goto out_sess;
123
124 device_shm = tee_shm_alloc_kernel_buf(ctx, shm_size);
125 if (IS_ERR(device_shm)) {
126 pr_err("tee_shm_alloc_kernel_buf failed\n");
127 rc = PTR_ERR(device_shm);
128 goto out_sess;
129 }
130
131 rc = get_devices(ctx, sess_arg.session, device_shm, &shm_size, func);
132 if (rc < 0)
133 goto out_shm;
134
135 device_uuid = tee_shm_get_va(device_shm, 0);
136 if (IS_ERR(device_uuid)) {
137 pr_err("tee_shm_get_va failed\n");
138 rc = PTR_ERR(device_uuid);
139 goto out_shm;
140 }
141
142 num_devices = shm_size / sizeof(uuid_t);
143
144 for (idx = 0; idx < num_devices; idx++) {
145 rc = optee_register_device(&device_uuid[idx]);
146 if (rc)
147 goto out_shm;
148 }
149
150 out_shm:
151 tee_shm_free(device_shm);
152 out_sess:
153 tee_client_close_session(ctx, sess_arg.session);
154 out_ctx:
155 tee_client_close_context(ctx);
156
157 return rc;
158 }
159
optee_enumerate_devices(u32 func)160 int optee_enumerate_devices(u32 func)
161 {
162 return __optee_enumerate_devices(func);
163 }
164
__optee_unregister_device(struct device * dev,void * data)165 static int __optee_unregister_device(struct device *dev, void *data)
166 {
167 if (!strncmp(dev_name(dev), "optee-ta", strlen("optee-ta")))
168 device_unregister(dev);
169
170 return 0;
171 }
172
optee_unregister_devices(void)173 void optee_unregister_devices(void)
174 {
175 bus_for_each_dev(&tee_bus_type, NULL, NULL,
176 __optee_unregister_device);
177 }
178