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
need_supplicant_show(struct device * dev,struct device_attribute * attr,char * buf)63 static ssize_t need_supplicant_show(struct device *dev,
64 struct device_attribute *attr,
65 char *buf)
66 {
67 return 0;
68 }
69
70 static DEVICE_ATTR_RO(need_supplicant);
71
optee_register_device(const uuid_t * device_uuid,u32 func)72 static int optee_register_device(const uuid_t *device_uuid, u32 func)
73 {
74 struct tee_client_device *optee_device = NULL;
75 int rc;
76
77 optee_device = kzalloc(sizeof(*optee_device), GFP_KERNEL);
78 if (!optee_device)
79 return -ENOMEM;
80
81 optee_device->dev.bus = &tee_bus_type;
82 optee_device->dev.release = optee_release_device;
83 if (dev_set_name(&optee_device->dev, "optee-ta-%pUb", device_uuid)) {
84 kfree(optee_device);
85 return -ENOMEM;
86 }
87 uuid_copy(&optee_device->id.uuid, device_uuid);
88
89 rc = device_register(&optee_device->dev);
90 if (rc) {
91 pr_err("device registration failed, err: %d\n", rc);
92 put_device(&optee_device->dev);
93 return rc;
94 }
95
96 if (func == PTA_CMD_GET_DEVICES_SUPP)
97 device_create_file(&optee_device->dev,
98 &dev_attr_need_supplicant);
99
100 return 0;
101 }
102
__optee_enumerate_devices(u32 func)103 static int __optee_enumerate_devices(u32 func)
104 {
105 const uuid_t pta_uuid =
106 UUID_INIT(0x7011a688, 0xddde, 0x4053,
107 0xa5, 0xa9, 0x7b, 0x3c, 0x4d, 0xdf, 0x13, 0xb8);
108 struct tee_ioctl_open_session_arg sess_arg;
109 struct tee_shm *device_shm = NULL;
110 const uuid_t *device_uuid = NULL;
111 struct tee_context *ctx = NULL;
112 u32 shm_size = 0, idx, num_devices = 0;
113 int rc;
114
115 memset(&sess_arg, 0, sizeof(sess_arg));
116
117 /* Open context with OP-TEE driver */
118 ctx = tee_client_open_context(NULL, optee_ctx_match, NULL, NULL);
119 if (IS_ERR(ctx))
120 return -ENODEV;
121
122 /* Open session with device enumeration pseudo TA */
123 export_uuid(sess_arg.uuid, &pta_uuid);
124 sess_arg.clnt_login = TEE_IOCTL_LOGIN_PUBLIC;
125 sess_arg.num_params = 0;
126
127 rc = tee_client_open_session(ctx, &sess_arg, NULL);
128 if ((rc < 0) || (sess_arg.ret != TEEC_SUCCESS)) {
129 /* Device enumeration pseudo TA not found */
130 rc = 0;
131 goto out_ctx;
132 }
133
134 rc = get_devices(ctx, sess_arg.session, NULL, &shm_size, func);
135 if (rc < 0 || !shm_size)
136 goto out_sess;
137
138 device_shm = tee_shm_alloc_kernel_buf(ctx, shm_size);
139 if (IS_ERR(device_shm)) {
140 pr_err("tee_shm_alloc_kernel_buf failed\n");
141 rc = PTR_ERR(device_shm);
142 goto out_sess;
143 }
144
145 rc = get_devices(ctx, sess_arg.session, device_shm, &shm_size, func);
146 if (rc < 0)
147 goto out_shm;
148
149 device_uuid = tee_shm_get_va(device_shm, 0);
150 if (IS_ERR(device_uuid)) {
151 pr_err("tee_shm_get_va failed\n");
152 rc = PTR_ERR(device_uuid);
153 goto out_shm;
154 }
155
156 num_devices = shm_size / sizeof(uuid_t);
157
158 for (idx = 0; idx < num_devices; idx++) {
159 rc = optee_register_device(&device_uuid[idx], func);
160 if (rc)
161 goto out_shm;
162 }
163
164 out_shm:
165 tee_shm_free(device_shm);
166 out_sess:
167 tee_client_close_session(ctx, sess_arg.session);
168 out_ctx:
169 tee_client_close_context(ctx);
170
171 return rc;
172 }
173
optee_enumerate_devices(u32 func)174 int optee_enumerate_devices(u32 func)
175 {
176 return __optee_enumerate_devices(func);
177 }
178
__optee_unregister_device(struct device * dev,void * data)179 static int __optee_unregister_device(struct device *dev, void *data)
180 {
181 if (!strncmp(dev_name(dev), "optee-ta", strlen("optee-ta")))
182 device_unregister(dev);
183
184 return 0;
185 }
186
optee_unregister_devices(void)187 void optee_unregister_devices(void)
188 {
189 bus_for_each_dev(&tee_bus_type, NULL, NULL,
190 __optee_unregister_device);
191 }
192