1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2014 STMicroelectronics SAS. All rights reserved.
4 */
5
6 #include <net/nfc/hci.h>
7
8 #include "st21nfca.h"
9
10 #define ST21NFCA_EVT_UICC_ACTIVATE 0x10
11 #define ST21NFCA_EVT_UICC_DEACTIVATE 0x13
12 #define ST21NFCA_EVT_SE_HARD_RESET 0x20
13 #define ST21NFCA_EVT_SE_SOFT_RESET 0x11
14 #define ST21NFCA_EVT_SE_END_OF_APDU_TRANSFER 0x21
15 #define ST21NFCA_EVT_SE_ACTIVATE 0x22
16 #define ST21NFCA_EVT_SE_DEACTIVATE 0x23
17
18 #define ST21NFCA_EVT_TRANSMIT_DATA 0x10
19 #define ST21NFCA_EVT_WTX_REQUEST 0x11
20
21 #define ST21NFCA_EVT_CONNECTIVITY 0x10
22 #define ST21NFCA_EVT_TRANSACTION 0x12
23
24 #define ST21NFCA_SE_TO_HOT_PLUG 1000
25 /* Connectivity pipe only */
26 #define ST21NFCA_SE_COUNT_PIPE_UICC 0x01
27 /* Connectivity + APDU Reader pipe */
28 #define ST21NFCA_SE_COUNT_PIPE_EMBEDDED 0x02
29
30 #define ST21NFCA_SE_MODE_OFF 0x00
31 #define ST21NFCA_SE_MODE_ON 0x01
32
33 #define ST21NFCA_PARAM_ATR 0x01
34 #define ST21NFCA_ATR_DEFAULT_BWI 0x04
35
36 /*
37 * WT = 2^BWI/10[s], convert into msecs and add a secure
38 * room by increasing by 2 this timeout
39 */
40 #define ST21NFCA_BWI_TO_TIMEOUT(x) ((1 << x) * 200)
41 #define ST21NFCA_ATR_GET_Y_FROM_TD(x) (x >> 4)
42
43 /* If TA is present bit 0 is set */
44 #define ST21NFCA_ATR_TA_PRESENT(x) (x & 0x01)
45 /* If TB is present bit 1 is set */
46 #define ST21NFCA_ATR_TB_PRESENT(x) (x & 0x02)
47
st21nfca_se_get_bwi(struct nfc_hci_dev * hdev)48 static u8 st21nfca_se_get_bwi(struct nfc_hci_dev *hdev)
49 {
50 int i;
51 u8 td;
52 struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
53
54 /* Bits 8 to 5 of the first TB for T=1 encode BWI from zero to nine */
55 for (i = 1; i < ST21NFCA_ESE_MAX_LENGTH; i++) {
56 td = ST21NFCA_ATR_GET_Y_FROM_TD(info->se_info.atr[i]);
57 if (ST21NFCA_ATR_TA_PRESENT(td))
58 i++;
59 if (ST21NFCA_ATR_TB_PRESENT(td)) {
60 i++;
61 return info->se_info.atr[i] >> 4;
62 }
63 }
64 return ST21NFCA_ATR_DEFAULT_BWI;
65 }
66
st21nfca_se_get_atr(struct nfc_hci_dev * hdev)67 static void st21nfca_se_get_atr(struct nfc_hci_dev *hdev)
68 {
69 int r;
70 struct sk_buff *skb;
71 struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
72
73 r = nfc_hci_get_param(hdev, ST21NFCA_APDU_READER_GATE,
74 ST21NFCA_PARAM_ATR, &skb);
75 if (r < 0)
76 return;
77
78 if (skb->len <= ST21NFCA_ESE_MAX_LENGTH) {
79 memcpy(info->se_info.atr, skb->data, skb->len);
80 info->se_info.wt_timeout =
81 ST21NFCA_BWI_TO_TIMEOUT(st21nfca_se_get_bwi(hdev));
82 }
83 kfree_skb(skb);
84 }
85
st21nfca_hci_control_se(struct nfc_hci_dev * hdev,u32 se_idx,u8 state)86 static int st21nfca_hci_control_se(struct nfc_hci_dev *hdev, u32 se_idx,
87 u8 state)
88 {
89 struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
90 int r, i;
91 struct sk_buff *sk_host_list;
92 u8 se_event, host_id;
93
94 switch (se_idx) {
95 case NFC_HCI_UICC_HOST_ID:
96 se_event = (state == ST21NFCA_SE_MODE_ON ?
97 ST21NFCA_EVT_UICC_ACTIVATE :
98 ST21NFCA_EVT_UICC_DEACTIVATE);
99
100 info->se_info.count_pipes = 0;
101 info->se_info.expected_pipes = ST21NFCA_SE_COUNT_PIPE_UICC;
102 break;
103 case ST21NFCA_ESE_HOST_ID:
104 se_event = (state == ST21NFCA_SE_MODE_ON ?
105 ST21NFCA_EVT_SE_ACTIVATE :
106 ST21NFCA_EVT_SE_DEACTIVATE);
107
108 info->se_info.count_pipes = 0;
109 info->se_info.expected_pipes = ST21NFCA_SE_COUNT_PIPE_EMBEDDED;
110 break;
111 default:
112 return -EINVAL;
113 }
114
115 /*
116 * Wait for an EVT_HOT_PLUG in order to
117 * retrieve a relevant host list.
118 */
119 reinit_completion(&info->se_info.req_completion);
120 r = nfc_hci_send_event(hdev, ST21NFCA_DEVICE_MGNT_GATE, se_event,
121 NULL, 0);
122 if (r < 0)
123 return r;
124
125 mod_timer(&info->se_info.se_active_timer, jiffies +
126 msecs_to_jiffies(ST21NFCA_SE_TO_HOT_PLUG));
127 info->se_info.se_active = true;
128
129 /* Ignore return value and check in any case the host_list */
130 wait_for_completion_interruptible(&info->se_info.req_completion);
131
132 r = nfc_hci_get_param(hdev, NFC_HCI_ADMIN_GATE,
133 NFC_HCI_ADMIN_HOST_LIST,
134 &sk_host_list);
135 if (r < 0)
136 return r;
137
138 for (i = 0; i < sk_host_list->len &&
139 sk_host_list->data[i] != se_idx; i++)
140 ;
141 host_id = sk_host_list->data[i];
142 kfree_skb(sk_host_list);
143
144 if (state == ST21NFCA_SE_MODE_ON && host_id == se_idx)
145 return se_idx;
146 else if (state == ST21NFCA_SE_MODE_OFF && host_id != se_idx)
147 return se_idx;
148
149 return -1;
150 }
151
st21nfca_hci_discover_se(struct nfc_hci_dev * hdev)152 int st21nfca_hci_discover_se(struct nfc_hci_dev *hdev)
153 {
154 struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
155 int se_count = 0;
156
157 if (test_bit(ST21NFCA_FACTORY_MODE, &hdev->quirks))
158 return 0;
159
160 if (info->se_status->is_uicc_present) {
161 nfc_add_se(hdev->ndev, NFC_HCI_UICC_HOST_ID, NFC_SE_UICC);
162 se_count++;
163 }
164
165 if (info->se_status->is_ese_present) {
166 nfc_add_se(hdev->ndev, ST21NFCA_ESE_HOST_ID, NFC_SE_EMBEDDED);
167 se_count++;
168 }
169
170 return !se_count;
171 }
172 EXPORT_SYMBOL(st21nfca_hci_discover_se);
173
st21nfca_hci_enable_se(struct nfc_hci_dev * hdev,u32 se_idx)174 int st21nfca_hci_enable_se(struct nfc_hci_dev *hdev, u32 se_idx)
175 {
176 int r;
177
178 /*
179 * According to upper layer, se_idx == NFC_SE_UICC when
180 * info->se_status->is_uicc_enable is true should never happen.
181 * Same for eSE.
182 */
183 r = st21nfca_hci_control_se(hdev, se_idx, ST21NFCA_SE_MODE_ON);
184 if (r == ST21NFCA_ESE_HOST_ID) {
185 st21nfca_se_get_atr(hdev);
186 r = nfc_hci_send_event(hdev, ST21NFCA_APDU_READER_GATE,
187 ST21NFCA_EVT_SE_SOFT_RESET, NULL, 0);
188 if (r < 0)
189 return r;
190 } else if (r < 0) {
191 /*
192 * The activation tentative failed, the secure element
193 * is not connected. Remove from the list.
194 */
195 nfc_remove_se(hdev->ndev, se_idx);
196 return r;
197 }
198
199 return 0;
200 }
201 EXPORT_SYMBOL(st21nfca_hci_enable_se);
202
st21nfca_hci_disable_se(struct nfc_hci_dev * hdev,u32 se_idx)203 int st21nfca_hci_disable_se(struct nfc_hci_dev *hdev, u32 se_idx)
204 {
205 int r;
206
207 /*
208 * According to upper layer, se_idx == NFC_SE_UICC when
209 * info->se_status->is_uicc_enable is true should never happen
210 * Same for eSE.
211 */
212 r = st21nfca_hci_control_se(hdev, se_idx, ST21NFCA_SE_MODE_OFF);
213 if (r < 0)
214 return r;
215
216 return 0;
217 }
218 EXPORT_SYMBOL(st21nfca_hci_disable_se);
219
st21nfca_hci_se_io(struct nfc_hci_dev * hdev,u32 se_idx,u8 * apdu,size_t apdu_length,se_io_cb_t cb,void * cb_context)220 int st21nfca_hci_se_io(struct nfc_hci_dev *hdev, u32 se_idx,
221 u8 *apdu, size_t apdu_length,
222 se_io_cb_t cb, void *cb_context)
223 {
224 struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
225
226 pr_debug("se_io %x\n", se_idx);
227
228 switch (se_idx) {
229 case ST21NFCA_ESE_HOST_ID:
230 info->se_info.cb = cb;
231 info->se_info.cb_context = cb_context;
232 mod_timer(&info->se_info.bwi_timer, jiffies +
233 msecs_to_jiffies(info->se_info.wt_timeout));
234 info->se_info.bwi_active = true;
235 return nfc_hci_send_event(hdev, ST21NFCA_APDU_READER_GATE,
236 ST21NFCA_EVT_TRANSMIT_DATA,
237 apdu, apdu_length);
238 default:
239 return -ENODEV;
240 }
241 }
242 EXPORT_SYMBOL(st21nfca_hci_se_io);
243
st21nfca_se_wt_timeout(struct timer_list * t)244 static void st21nfca_se_wt_timeout(struct timer_list *t)
245 {
246 /*
247 * No answer from the secure element
248 * within the defined timeout.
249 * Let's send a reset request as recovery procedure.
250 * According to the situation, we first try to send a software reset
251 * to the secure element. If the next command is still not
252 * answering in time, we send to the CLF a secure element hardware
253 * reset request.
254 */
255 /* hardware reset managed through VCC_UICC_OUT power supply */
256 u8 param = 0x01;
257 struct st21nfca_hci_info *info = from_timer(info, t,
258 se_info.bwi_timer);
259
260 info->se_info.bwi_active = false;
261
262 if (!info->se_info.xch_error) {
263 info->se_info.xch_error = true;
264 nfc_hci_send_event(info->hdev, ST21NFCA_APDU_READER_GATE,
265 ST21NFCA_EVT_SE_SOFT_RESET, NULL, 0);
266 } else {
267 info->se_info.xch_error = false;
268 nfc_hci_send_event(info->hdev, ST21NFCA_DEVICE_MGNT_GATE,
269 ST21NFCA_EVT_SE_HARD_RESET, ¶m, 1);
270 }
271 info->se_info.cb(info->se_info.cb_context, NULL, 0, -ETIME);
272 }
273
st21nfca_se_activation_timeout(struct timer_list * t)274 static void st21nfca_se_activation_timeout(struct timer_list *t)
275 {
276 struct st21nfca_hci_info *info = from_timer(info, t,
277 se_info.se_active_timer);
278
279 info->se_info.se_active = false;
280
281 complete(&info->se_info.req_completion);
282 }
283
284 /*
285 * Returns:
286 * <= 0: driver handled the event, skb consumed
287 * 1: driver does not handle the event, please do standard processing
288 */
st21nfca_connectivity_event_received(struct nfc_hci_dev * hdev,u8 host,u8 event,struct sk_buff * skb)289 int st21nfca_connectivity_event_received(struct nfc_hci_dev *hdev, u8 host,
290 u8 event, struct sk_buff *skb)
291 {
292 int r = 0;
293 struct device *dev = &hdev->ndev->dev;
294 struct nfc_evt_transaction *transaction;
295
296 pr_debug("connectivity gate event: %x\n", event);
297
298 switch (event) {
299 case ST21NFCA_EVT_CONNECTIVITY:
300 r = nfc_se_connectivity(hdev->ndev, host);
301 break;
302 case ST21NFCA_EVT_TRANSACTION:
303 /*
304 * According to specification etsi 102 622
305 * 11.2.2.4 EVT_TRANSACTION Table 52
306 * Description Tag Length
307 * AID 81 5 to 16
308 * PARAMETERS 82 0 to 255
309 */
310 if (skb->len < NFC_MIN_AID_LENGTH + 2 &&
311 skb->data[0] != NFC_EVT_TRANSACTION_AID_TAG)
312 return -EPROTO;
313
314 transaction = devm_kzalloc(dev, skb->len - 2, GFP_KERNEL);
315 if (!transaction)
316 return -ENOMEM;
317
318 transaction->aid_len = skb->data[1];
319 memcpy(transaction->aid, &skb->data[2],
320 transaction->aid_len);
321
322 /* Check next byte is PARAMETERS tag (82) */
323 if (skb->data[transaction->aid_len + 2] !=
324 NFC_EVT_TRANSACTION_PARAMS_TAG)
325 return -EPROTO;
326
327 transaction->params_len = skb->data[transaction->aid_len + 3];
328 memcpy(transaction->params, skb->data +
329 transaction->aid_len + 4, transaction->params_len);
330
331 r = nfc_se_transaction(hdev->ndev, host, transaction);
332 break;
333 default:
334 nfc_err(&hdev->ndev->dev, "Unexpected event on connectivity gate\n");
335 return 1;
336 }
337 kfree_skb(skb);
338 return r;
339 }
340 EXPORT_SYMBOL(st21nfca_connectivity_event_received);
341
st21nfca_apdu_reader_event_received(struct nfc_hci_dev * hdev,u8 event,struct sk_buff * skb)342 int st21nfca_apdu_reader_event_received(struct nfc_hci_dev *hdev,
343 u8 event, struct sk_buff *skb)
344 {
345 int r = 0;
346 struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
347
348 pr_debug("apdu reader gate event: %x\n", event);
349
350 switch (event) {
351 case ST21NFCA_EVT_TRANSMIT_DATA:
352 del_timer_sync(&info->se_info.bwi_timer);
353 info->se_info.bwi_active = false;
354 r = nfc_hci_send_event(hdev, ST21NFCA_DEVICE_MGNT_GATE,
355 ST21NFCA_EVT_SE_END_OF_APDU_TRANSFER, NULL, 0);
356 if (r < 0)
357 goto exit;
358
359 info->se_info.cb(info->se_info.cb_context,
360 skb->data, skb->len, 0);
361 break;
362 case ST21NFCA_EVT_WTX_REQUEST:
363 mod_timer(&info->se_info.bwi_timer, jiffies +
364 msecs_to_jiffies(info->se_info.wt_timeout));
365 break;
366 default:
367 nfc_err(&hdev->ndev->dev, "Unexpected event on apdu reader gate\n");
368 return 1;
369 }
370
371 exit:
372 kfree_skb(skb);
373 return r;
374 }
375 EXPORT_SYMBOL(st21nfca_apdu_reader_event_received);
376
st21nfca_se_init(struct nfc_hci_dev * hdev)377 void st21nfca_se_init(struct nfc_hci_dev *hdev)
378 {
379 struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
380
381 init_completion(&info->se_info.req_completion);
382 /* initialize timers */
383 timer_setup(&info->se_info.bwi_timer, st21nfca_se_wt_timeout, 0);
384 info->se_info.bwi_active = false;
385
386 timer_setup(&info->se_info.se_active_timer,
387 st21nfca_se_activation_timeout, 0);
388 info->se_info.se_active = false;
389
390 info->se_info.count_pipes = 0;
391 info->se_info.expected_pipes = 0;
392
393 info->se_info.xch_error = false;
394
395 info->se_info.wt_timeout =
396 ST21NFCA_BWI_TO_TIMEOUT(ST21NFCA_ATR_DEFAULT_BWI);
397 }
398 EXPORT_SYMBOL(st21nfca_se_init);
399
st21nfca_se_deinit(struct nfc_hci_dev * hdev)400 void st21nfca_se_deinit(struct nfc_hci_dev *hdev)
401 {
402 struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
403
404 if (info->se_info.bwi_active)
405 del_timer_sync(&info->se_info.bwi_timer);
406 if (info->se_info.se_active)
407 del_timer_sync(&info->se_info.se_active_timer);
408
409 info->se_info.bwi_active = false;
410 info->se_info.se_active = false;
411 }
412 EXPORT_SYMBOL(st21nfca_se_deinit);
413