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9#include <linux/err.h>
10#include <linux/key-type.h>
11#include <linux/module.h>
12#include <linux/slab.h>
13#include <linux/string.h>
14#include <linux/tee_drv.h>
15#include <linux/uuid.h>
16
17#include <keys/trusted_tee.h>
18
19#define DRIVER_NAME "trusted-key-tee"
20
21
22
23
24
25
26#define TA_CMD_GET_RANDOM 0x0
27
28
29
30
31
32
33
34#define TA_CMD_SEAL 0x1
35
36
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38
39
40
41
42#define TA_CMD_UNSEAL 0x2
43
44
45
46
47
48
49
50
51struct trusted_key_tee_private {
52 struct device *dev;
53 struct tee_context *ctx;
54 u32 session_id;
55 struct tee_shm *shm_pool;
56};
57
58static struct trusted_key_tee_private pvt_data;
59
60
61
62
63static int trusted_tee_seal(struct trusted_key_payload *p, char *datablob)
64{
65 int ret;
66 struct tee_ioctl_invoke_arg inv_arg;
67 struct tee_param param[4];
68 struct tee_shm *reg_shm_in = NULL, *reg_shm_out = NULL;
69
70 memset(&inv_arg, 0, sizeof(inv_arg));
71 memset(¶m, 0, sizeof(param));
72
73 reg_shm_in = tee_shm_register(pvt_data.ctx, (unsigned long)p->key,
74 p->key_len, TEE_SHM_DMA_BUF |
75 TEE_SHM_KERNEL_MAPPED);
76 if (IS_ERR(reg_shm_in)) {
77 dev_err(pvt_data.dev, "key shm register failed\n");
78 return PTR_ERR(reg_shm_in);
79 }
80
81 reg_shm_out = tee_shm_register(pvt_data.ctx, (unsigned long)p->blob,
82 sizeof(p->blob), TEE_SHM_DMA_BUF |
83 TEE_SHM_KERNEL_MAPPED);
84 if (IS_ERR(reg_shm_out)) {
85 dev_err(pvt_data.dev, "blob shm register failed\n");
86 ret = PTR_ERR(reg_shm_out);
87 goto out;
88 }
89
90 inv_arg.func = TA_CMD_SEAL;
91 inv_arg.session = pvt_data.session_id;
92 inv_arg.num_params = 4;
93
94 param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT;
95 param[0].u.memref.shm = reg_shm_in;
96 param[0].u.memref.size = p->key_len;
97 param[0].u.memref.shm_offs = 0;
98 param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT;
99 param[1].u.memref.shm = reg_shm_out;
100 param[1].u.memref.size = sizeof(p->blob);
101 param[1].u.memref.shm_offs = 0;
102
103 ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param);
104 if ((ret < 0) || (inv_arg.ret != 0)) {
105 dev_err(pvt_data.dev, "TA_CMD_SEAL invoke err: %x\n",
106 inv_arg.ret);
107 ret = -EFAULT;
108 } else {
109 p->blob_len = param[1].u.memref.size;
110 }
111
112out:
113 if (reg_shm_out)
114 tee_shm_free(reg_shm_out);
115 if (reg_shm_in)
116 tee_shm_free(reg_shm_in);
117
118 return ret;
119}
120
121
122
123
124static int trusted_tee_unseal(struct trusted_key_payload *p, char *datablob)
125{
126 int ret;
127 struct tee_ioctl_invoke_arg inv_arg;
128 struct tee_param param[4];
129 struct tee_shm *reg_shm_in = NULL, *reg_shm_out = NULL;
130
131 memset(&inv_arg, 0, sizeof(inv_arg));
132 memset(¶m, 0, sizeof(param));
133
134 reg_shm_in = tee_shm_register(pvt_data.ctx, (unsigned long)p->blob,
135 p->blob_len, TEE_SHM_DMA_BUF |
136 TEE_SHM_KERNEL_MAPPED);
137 if (IS_ERR(reg_shm_in)) {
138 dev_err(pvt_data.dev, "blob shm register failed\n");
139 return PTR_ERR(reg_shm_in);
140 }
141
142 reg_shm_out = tee_shm_register(pvt_data.ctx, (unsigned long)p->key,
143 sizeof(p->key), TEE_SHM_DMA_BUF |
144 TEE_SHM_KERNEL_MAPPED);
145 if (IS_ERR(reg_shm_out)) {
146 dev_err(pvt_data.dev, "key shm register failed\n");
147 ret = PTR_ERR(reg_shm_out);
148 goto out;
149 }
150
151 inv_arg.func = TA_CMD_UNSEAL;
152 inv_arg.session = pvt_data.session_id;
153 inv_arg.num_params = 4;
154
155 param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT;
156 param[0].u.memref.shm = reg_shm_in;
157 param[0].u.memref.size = p->blob_len;
158 param[0].u.memref.shm_offs = 0;
159 param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT;
160 param[1].u.memref.shm = reg_shm_out;
161 param[1].u.memref.size = sizeof(p->key);
162 param[1].u.memref.shm_offs = 0;
163
164 ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param);
165 if ((ret < 0) || (inv_arg.ret != 0)) {
166 dev_err(pvt_data.dev, "TA_CMD_UNSEAL invoke err: %x\n",
167 inv_arg.ret);
168 ret = -EFAULT;
169 } else {
170 p->key_len = param[1].u.memref.size;
171 }
172
173out:
174 if (reg_shm_out)
175 tee_shm_free(reg_shm_out);
176 if (reg_shm_in)
177 tee_shm_free(reg_shm_in);
178
179 return ret;
180}
181
182
183
184
185static int trusted_tee_get_random(unsigned char *key, size_t key_len)
186{
187 int ret;
188 struct tee_ioctl_invoke_arg inv_arg;
189 struct tee_param param[4];
190 struct tee_shm *reg_shm = NULL;
191
192 memset(&inv_arg, 0, sizeof(inv_arg));
193 memset(¶m, 0, sizeof(param));
194
195 reg_shm = tee_shm_register(pvt_data.ctx, (unsigned long)key, key_len,
196 TEE_SHM_DMA_BUF | TEE_SHM_KERNEL_MAPPED);
197 if (IS_ERR(reg_shm)) {
198 dev_err(pvt_data.dev, "key shm register failed\n");
199 return PTR_ERR(reg_shm);
200 }
201
202 inv_arg.func = TA_CMD_GET_RANDOM;
203 inv_arg.session = pvt_data.session_id;
204 inv_arg.num_params = 4;
205
206 param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT;
207 param[0].u.memref.shm = reg_shm;
208 param[0].u.memref.size = key_len;
209 param[0].u.memref.shm_offs = 0;
210
211 ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param);
212 if ((ret < 0) || (inv_arg.ret != 0)) {
213 dev_err(pvt_data.dev, "TA_CMD_GET_RANDOM invoke err: %x\n",
214 inv_arg.ret);
215 ret = -EFAULT;
216 } else {
217 ret = param[0].u.memref.size;
218 }
219
220 tee_shm_free(reg_shm);
221
222 return ret;
223}
224
225static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
226{
227 if (ver->impl_id == TEE_IMPL_ID_OPTEE)
228 return 1;
229 else
230 return 0;
231}
232
233static int trusted_key_probe(struct device *dev)
234{
235 struct tee_client_device *rng_device = to_tee_client_device(dev);
236 int ret;
237 struct tee_ioctl_open_session_arg sess_arg;
238
239 memset(&sess_arg, 0, sizeof(sess_arg));
240
241 pvt_data.ctx = tee_client_open_context(NULL, optee_ctx_match, NULL,
242 NULL);
243 if (IS_ERR(pvt_data.ctx))
244 return -ENODEV;
245
246 memcpy(sess_arg.uuid, rng_device->id.uuid.b, TEE_IOCTL_UUID_LEN);
247 sess_arg.clnt_login = TEE_IOCTL_LOGIN_REE_KERNEL;
248 sess_arg.num_params = 0;
249
250 ret = tee_client_open_session(pvt_data.ctx, &sess_arg, NULL);
251 if ((ret < 0) || (sess_arg.ret != 0)) {
252 dev_err(dev, "tee_client_open_session failed, err: %x\n",
253 sess_arg.ret);
254 ret = -EINVAL;
255 goto out_ctx;
256 }
257 pvt_data.session_id = sess_arg.session;
258
259 ret = register_key_type(&key_type_trusted);
260 if (ret < 0)
261 goto out_sess;
262
263 pvt_data.dev = dev;
264
265 return 0;
266
267out_sess:
268 tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
269out_ctx:
270 tee_client_close_context(pvt_data.ctx);
271
272 return ret;
273}
274
275static int trusted_key_remove(struct device *dev)
276{
277 unregister_key_type(&key_type_trusted);
278 tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
279 tee_client_close_context(pvt_data.ctx);
280
281 return 0;
282}
283
284static const struct tee_client_device_id trusted_key_id_table[] = {
285 {UUID_INIT(0xf04a0fe7, 0x1f5d, 0x4b9b,
286 0xab, 0xf7, 0x61, 0x9b, 0x85, 0xb4, 0xce, 0x8c)},
287 {}
288};
289MODULE_DEVICE_TABLE(tee, trusted_key_id_table);
290
291static struct tee_client_driver trusted_key_driver = {
292 .id_table = trusted_key_id_table,
293 .driver = {
294 .name = DRIVER_NAME,
295 .bus = &tee_bus_type,
296 .probe = trusted_key_probe,
297 .remove = trusted_key_remove,
298 },
299};
300
301static int trusted_tee_init(void)
302{
303 return driver_register(&trusted_key_driver.driver);
304}
305
306static void trusted_tee_exit(void)
307{
308 driver_unregister(&trusted_key_driver.driver);
309}
310
311struct trusted_key_ops trusted_key_tee_ops = {
312 .migratable = 0,
313 .init = trusted_tee_init,
314 .seal = trusted_tee_seal,
315 .unseal = trusted_tee_unseal,
316 .get_random = trusted_tee_get_random,
317 .exit = trusted_tee_exit,
318};
319
