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1/*
2 BlueZ - Bluetooth protocol stack for Linux
3 Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License version 2 as
7 published by the Free Software Foundation;
8
9 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
10 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
11 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
12 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
13 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
14 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17
18 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
19 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
20 SOFTWARE IS DISCLAIMED.
21*/
22
23#include <net/bluetooth/bluetooth.h>
24#include <net/bluetooth/hci_core.h>
25#include <net/bluetooth/l2cap.h>
26#include <net/bluetooth/mgmt.h>
27#include <net/bluetooth/smp.h>
28#include <linux/crypto.h>
29#include <linux/scatterlist.h>
30#include <crypto/b128ops.h>
31
32#define SMP_TIMEOUT msecs_to_jiffies(30000)
33
34static inline void swap128(u8 src[16], u8 dst[16])
35{
36 int i;
37 for (i = 0; i < 16; i++)
38 dst[15 - i] = src[i];
39}
40
41static inline void swap56(u8 src[7], u8 dst[7])
42{
43 int i;
44 for (i = 0; i < 7; i++)
45 dst[6 - i] = src[i];
46}
47
48static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r)
49{
50 struct blkcipher_desc desc;
51 struct scatterlist sg;
52 int err, iv_len;
53 unsigned char iv[128];
54
55 if (tfm == NULL) {
56 BT_ERR("tfm %p", tfm);
57 return -EINVAL;
58 }
59
60 desc.tfm = tfm;
61 desc.flags = 0;
62
63 err = crypto_blkcipher_setkey(tfm, k, 16);
64 if (err) {
65 BT_ERR("cipher setkey failed: %d", err);
66 return err;
67 }
68
69 sg_init_one(&sg, r, 16);
70
71 iv_len = crypto_blkcipher_ivsize(tfm);
72 if (iv_len) {
73 memset(&iv, 0xff, iv_len);
74 crypto_blkcipher_set_iv(tfm, iv, iv_len);
75 }
76
77 err = crypto_blkcipher_encrypt(&desc, &sg, &sg, 16);
78 if (err)
79 BT_ERR("Encrypt data error %d", err);
80
81 return err;
82}
83
84static int smp_c1(struct crypto_blkcipher *tfm, u8 k[16], u8 r[16],
85 u8 preq[7], u8 pres[7], u8 _iat, bdaddr_t *ia,
86 u8 _rat, bdaddr_t *ra, u8 res[16])
87{
88 u8 p1[16], p2[16];
89 int err;
90
91 memset(p1, 0, 16);
92
93 /* p1 = pres || preq || _rat || _iat */
94 swap56(pres, p1);
95 swap56(preq, p1 + 7);
96 p1[14] = _rat;
97 p1[15] = _iat;
98
99 memset(p2, 0, 16);
100
101 /* p2 = padding || ia || ra */
102 baswap((bdaddr_t *) (p2 + 4), ia);
103 baswap((bdaddr_t *) (p2 + 10), ra);
104
105 /* res = r XOR p1 */
106 u128_xor((u128 *) res, (u128 *) r, (u128 *) p1);
107
108 /* res = e(k, res) */
109 err = smp_e(tfm, k, res);
110 if (err) {
111 BT_ERR("Encrypt data error");
112 return err;
113 }
114
115 /* res = res XOR p2 */
116 u128_xor((u128 *) res, (u128 *) res, (u128 *) p2);
117
118 /* res = e(k, res) */
119 err = smp_e(tfm, k, res);
120 if (err)
121 BT_ERR("Encrypt data error");
122
123 return err;
124}
125
126static int smp_s1(struct crypto_blkcipher *tfm, u8 k[16],
127 u8 r1[16], u8 r2[16], u8 _r[16])
128{
129 int err;
130
131 /* Just least significant octets from r1 and r2 are considered */
132 memcpy(_r, r1 + 8, 8);
133 memcpy(_r + 8, r2 + 8, 8);
134
135 err = smp_e(tfm, k, _r);
136 if (err)
137 BT_ERR("Encrypt data error");
138
139 return err;
140}
141
142static int smp_rand(u8 *buf)
143{
144 get_random_bytes(buf, 16);
145
146 return 0;
147}
148
149static struct sk_buff *smp_build_cmd(struct l2cap_conn *conn, u8 code,
150 u16 dlen, void *data)
151{
152 struct sk_buff *skb;
153 struct l2cap_hdr *lh;
154 int len;
155
156 len = L2CAP_HDR_SIZE + sizeof(code) + dlen;
157
158 if (len > conn->mtu)
159 return NULL;
160
161 skb = bt_skb_alloc(len, GFP_ATOMIC);
162 if (!skb)
163 return NULL;
164
165 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
166 lh->len = cpu_to_le16(sizeof(code) + dlen);
167 lh->cid = cpu_to_le16(L2CAP_CID_SMP);
168
169 memcpy(skb_put(skb, sizeof(code)), &code, sizeof(code));
170
171 memcpy(skb_put(skb, dlen), data, dlen);
172
173 return skb;
174}
175
176static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
177{
178 struct sk_buff *skb = smp_build_cmd(conn, code, len, data);
179
180 BT_DBG("code 0x%2.2x", code);
181
182 if (!skb)
183 return;
184
185 skb->priority = HCI_PRIO_MAX;
186 hci_send_acl(conn->hchan, skb, 0);
187
188 cancel_delayed_work_sync(&conn->security_timer);
189 schedule_delayed_work(&conn->security_timer, SMP_TIMEOUT);
190}
191
192static __u8 authreq_to_seclevel(__u8 authreq)
193{
194 if (authreq & SMP_AUTH_MITM)
195 return BT_SECURITY_HIGH;
196 else
197 return BT_SECURITY_MEDIUM;
198}
199
200static __u8 seclevel_to_authreq(__u8 sec_level)
201{
202 switch (sec_level) {
203 case BT_SECURITY_HIGH:
204 return SMP_AUTH_MITM | SMP_AUTH_BONDING;
205 case BT_SECURITY_MEDIUM:
206 return SMP_AUTH_BONDING;
207 default:
208 return SMP_AUTH_NONE;
209 }
210}
211
212static void build_pairing_cmd(struct l2cap_conn *conn,
213 struct smp_cmd_pairing *req,
214 struct smp_cmd_pairing *rsp,
215 __u8 authreq)
216{
217 u8 dist_keys = 0;
218
219 if (test_bit(HCI_PAIRABLE, &conn->hcon->hdev->dev_flags)) {
220 dist_keys = SMP_DIST_ENC_KEY;
221 authreq |= SMP_AUTH_BONDING;
222 } else {
223 authreq &= ~SMP_AUTH_BONDING;
224 }
225
226 if (rsp == NULL) {
227 req->io_capability = conn->hcon->io_capability;
228 req->oob_flag = SMP_OOB_NOT_PRESENT;
229 req->max_key_size = SMP_MAX_ENC_KEY_SIZE;
230 req->init_key_dist = 0;
231 req->resp_key_dist = dist_keys;
232 req->auth_req = authreq;
233 return;
234 }
235
236 rsp->io_capability = conn->hcon->io_capability;
237 rsp->oob_flag = SMP_OOB_NOT_PRESENT;
238 rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
239 rsp->init_key_dist = 0;
240 rsp->resp_key_dist = req->resp_key_dist & dist_keys;
241 rsp->auth_req = authreq;
242}
243
244static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)
245{
246 struct smp_chan *smp = conn->smp_chan;
247
248 if ((max_key_size > SMP_MAX_ENC_KEY_SIZE) ||
249 (max_key_size < SMP_MIN_ENC_KEY_SIZE))
250 return SMP_ENC_KEY_SIZE;
251
252 smp->enc_key_size = max_key_size;
253
254 return 0;
255}
256
257static void smp_failure(struct l2cap_conn *conn, u8 reason, u8 send)
258{
259 struct hci_conn *hcon = conn->hcon;
260
261 if (send)
262 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
263 &reason);
264
265 clear_bit(HCI_CONN_ENCRYPT_PEND, &conn->hcon->flags);
266 mgmt_auth_failed(conn->hcon->hdev, conn->dst, hcon->type,
267 hcon->dst_type, reason);
268
269 cancel_delayed_work_sync(&conn->security_timer);
270
271 if (test_and_clear_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->flags))
272 smp_chan_destroy(conn);
273}
274
275#define JUST_WORKS 0x00
276#define JUST_CFM 0x01
277#define REQ_PASSKEY 0x02
278#define CFM_PASSKEY 0x03
279#define REQ_OOB 0x04
280#define OVERLAP 0xFF
281
282static const u8 gen_method[5][5] = {
283 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
284 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
285 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
286 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
287 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP },
288};
289
290static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
291 u8 local_io, u8 remote_io)
292{
293 struct hci_conn *hcon = conn->hcon;
294 struct smp_chan *smp = conn->smp_chan;
295 u8 method;
296 u32 passkey = 0;
297 int ret = 0;
298
299 /* Initialize key for JUST WORKS */
300 memset(smp->tk, 0, sizeof(smp->tk));
301 clear_bit(SMP_FLAG_TK_VALID, &smp->smp_flags);
302
303 BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io);
304
305 /* If neither side wants MITM, use JUST WORKS */
306 /* If either side has unknown io_caps, use JUST WORKS */
307 /* Otherwise, look up method from the table */
308 if (!(auth & SMP_AUTH_MITM) ||
309 local_io > SMP_IO_KEYBOARD_DISPLAY ||
310 remote_io > SMP_IO_KEYBOARD_DISPLAY)
311 method = JUST_WORKS;
312 else
313 method = gen_method[remote_io][local_io];
314
315 /* If not bonding, don't ask user to confirm a Zero TK */
316 if (!(auth & SMP_AUTH_BONDING) && method == JUST_CFM)
317 method = JUST_WORKS;
318
319 /* If Just Works, Continue with Zero TK */
320 if (method == JUST_WORKS) {
321 set_bit(SMP_FLAG_TK_VALID, &smp->smp_flags);
322 return 0;
323 }
324
325 /* Not Just Works/Confirm results in MITM Authentication */
326 if (method != JUST_CFM)
327 set_bit(SMP_FLAG_MITM_AUTH, &smp->smp_flags);
328
329 /* If both devices have Keyoard-Display I/O, the master
330 * Confirms and the slave Enters the passkey.
331 */
332 if (method == OVERLAP) {
333 if (hcon->link_mode & HCI_LM_MASTER)
334 method = CFM_PASSKEY;
335 else
336 method = REQ_PASSKEY;
337 }
338
339 /* Generate random passkey. Not valid until confirmed. */
340 if (method == CFM_PASSKEY) {
341 u8 key[16];
342
343 memset(key, 0, sizeof(key));
344 get_random_bytes(&passkey, sizeof(passkey));
345 passkey %= 1000000;
346 put_unaligned_le32(passkey, key);
347 swap128(key, smp->tk);
348 BT_DBG("PassKey: %d", passkey);
349 }
350
351 hci_dev_lock(hcon->hdev);
352
353 if (method == REQ_PASSKEY)
354 ret = mgmt_user_passkey_request(hcon->hdev, conn->dst,
355 hcon->type, hcon->dst_type);
356 else
357 ret = mgmt_user_confirm_request(hcon->hdev, conn->dst,
358 hcon->type, hcon->dst_type,
359 cpu_to_le32(passkey), 0);
360
361 hci_dev_unlock(hcon->hdev);
362
363 return ret;
364}
365
366static void confirm_work(struct work_struct *work)
367{
368 struct smp_chan *smp = container_of(work, struct smp_chan, confirm);
369 struct l2cap_conn *conn = smp->conn;
370 struct crypto_blkcipher *tfm;
371 struct smp_cmd_pairing_confirm cp;
372 int ret;
373 u8 res[16], reason;
374
375 BT_DBG("conn %p", conn);
376
377 tfm = crypto_alloc_blkcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
378 if (IS_ERR(tfm)) {
379 reason = SMP_UNSPECIFIED;
380 goto error;
381 }
382
383 smp->tfm = tfm;
384
385 if (conn->hcon->out)
386 ret = smp_c1(tfm, smp->tk, smp->prnd, smp->preq, smp->prsp, 0,
387 conn->src, conn->hcon->dst_type, conn->dst, res);
388 else
389 ret = smp_c1(tfm, smp->tk, smp->prnd, smp->preq, smp->prsp,
390 conn->hcon->dst_type, conn->dst, 0, conn->src,
391 res);
392 if (ret) {
393 reason = SMP_UNSPECIFIED;
394 goto error;
395 }
396
397 clear_bit(SMP_FLAG_CFM_PENDING, &smp->smp_flags);
398
399 swap128(res, cp.confirm_val);
400 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
401
402 return;
403
404error:
405 smp_failure(conn, reason, 1);
406}
407
408static void random_work(struct work_struct *work)
409{
410 struct smp_chan *smp = container_of(work, struct smp_chan, random);
411 struct l2cap_conn *conn = smp->conn;
412 struct hci_conn *hcon = conn->hcon;
413 struct crypto_blkcipher *tfm = smp->tfm;
414 u8 reason, confirm[16], res[16], key[16];
415 int ret;
416
417 if (IS_ERR_OR_NULL(tfm)) {
418 reason = SMP_UNSPECIFIED;
419 goto error;
420 }
421
422 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
423
424 if (hcon->out)
425 ret = smp_c1(tfm, smp->tk, smp->rrnd, smp->preq, smp->prsp, 0,
426 conn->src, hcon->dst_type, conn->dst, res);
427 else
428 ret = smp_c1(tfm, smp->tk, smp->rrnd, smp->preq, smp->prsp,
429 hcon->dst_type, conn->dst, 0, conn->src, res);
430 if (ret) {
431 reason = SMP_UNSPECIFIED;
432 goto error;
433 }
434
435 swap128(res, confirm);
436
437 if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) {
438 BT_ERR("Pairing failed (confirmation values mismatch)");
439 reason = SMP_CONFIRM_FAILED;
440 goto error;
441 }
442
443 if (hcon->out) {
444 u8 stk[16], rand[8];
445 __le16 ediv;
446
447 memset(rand, 0, sizeof(rand));
448 ediv = 0;
449
450 smp_s1(tfm, smp->tk, smp->rrnd, smp->prnd, key);
451 swap128(key, stk);
452
453 memset(stk + smp->enc_key_size, 0,
454 SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size);
455
456 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) {
457 reason = SMP_UNSPECIFIED;
458 goto error;
459 }
460
461 hci_le_start_enc(hcon, ediv, rand, stk);
462 hcon->enc_key_size = smp->enc_key_size;
463 } else {
464 u8 stk[16], r[16], rand[8];
465 __le16 ediv;
466
467 memset(rand, 0, sizeof(rand));
468 ediv = 0;
469
470 swap128(smp->prnd, r);
471 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(r), r);
472
473 smp_s1(tfm, smp->tk, smp->prnd, smp->rrnd, key);
474 swap128(key, stk);
475
476 memset(stk + smp->enc_key_size, 0,
477 SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size);
478
479 hci_add_ltk(hcon->hdev, conn->dst, hcon->dst_type,
480 HCI_SMP_STK_SLAVE, 0, 0, stk, smp->enc_key_size,
481 ediv, rand);
482 }
483
484 return;
485
486error:
487 smp_failure(conn, reason, 1);
488}
489
490static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
491{
492 struct smp_chan *smp;
493
494 smp = kzalloc(sizeof(struct smp_chan), GFP_ATOMIC);
495 if (!smp)
496 return NULL;
497
498 INIT_WORK(&smp->confirm, confirm_work);
499 INIT_WORK(&smp->random, random_work);
500
501 smp->conn = conn;
502 conn->smp_chan = smp;
503 conn->hcon->smp_conn = conn;
504
505 hci_conn_hold(conn->hcon);
506
507 return smp;
508}
509
510void smp_chan_destroy(struct l2cap_conn *conn)
511{
512 struct smp_chan *smp = conn->smp_chan;
513
514 BUG_ON(!smp);
515
516 if (smp->tfm)
517 crypto_free_blkcipher(smp->tfm);
518
519 kfree(smp);
520 conn->smp_chan = NULL;
521 conn->hcon->smp_conn = NULL;
522 hci_conn_put(conn->hcon);
523}
524
525int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
526{
527 struct l2cap_conn *conn = hcon->smp_conn;
528 struct smp_chan *smp;
529 u32 value;
530 u8 key[16];
531
532 BT_DBG("");
533
534 if (!conn)
535 return -ENOTCONN;
536
537 smp = conn->smp_chan;
538
539 switch (mgmt_op) {
540 case MGMT_OP_USER_PASSKEY_REPLY:
541 value = le32_to_cpu(passkey);
542 memset(key, 0, sizeof(key));
543 BT_DBG("PassKey: %d", value);
544 put_unaligned_le32(value, key);
545 swap128(key, smp->tk);
546 /* Fall Through */
547 case MGMT_OP_USER_CONFIRM_REPLY:
548 set_bit(SMP_FLAG_TK_VALID, &smp->smp_flags);
549 break;
550 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
551 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
552 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED, 1);
553 return 0;
554 default:
555 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED, 1);
556 return -EOPNOTSUPP;
557 }
558
559 /* If it is our turn to send Pairing Confirm, do so now */
560 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->smp_flags))
561 queue_work(hcon->hdev->workqueue, &smp->confirm);
562
563 return 0;
564}
565
566static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
567{
568 struct smp_cmd_pairing rsp, *req = (void *) skb->data;
569 struct smp_chan *smp;
570 u8 key_size;
571 u8 auth = SMP_AUTH_NONE;
572 int ret;
573
574 BT_DBG("conn %p", conn);
575
576 if (conn->hcon->link_mode & HCI_LM_MASTER)
577 return SMP_CMD_NOTSUPP;
578
579 if (!test_and_set_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->flags))
580 smp = smp_chan_create(conn);
581
582 smp = conn->smp_chan;
583
584 smp->preq[0] = SMP_CMD_PAIRING_REQ;
585 memcpy(&smp->preq[1], req, sizeof(*req));
586 skb_pull(skb, sizeof(*req));
587
588 /* We didn't start the pairing, so match remote */
589 if (req->auth_req & SMP_AUTH_BONDING)
590 auth = req->auth_req;
591
592 conn->hcon->pending_sec_level = authreq_to_seclevel(auth);
593
594 build_pairing_cmd(conn, req, &rsp, auth);
595
596 key_size = min(req->max_key_size, rsp.max_key_size);
597 if (check_enc_key_size(conn, key_size))
598 return SMP_ENC_KEY_SIZE;
599
600 ret = smp_rand(smp->prnd);
601 if (ret)
602 return SMP_UNSPECIFIED;
603
604 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
605 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
606
607 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
608
609 /* Request setup of TK */
610 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability);
611 if (ret)
612 return SMP_UNSPECIFIED;
613
614 return 0;
615}
616
617static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
618{
619 struct smp_cmd_pairing *req, *rsp = (void *) skb->data;
620 struct smp_chan *smp = conn->smp_chan;
621 struct hci_dev *hdev = conn->hcon->hdev;
622 u8 key_size, auth = SMP_AUTH_NONE;
623 int ret;
624
625 BT_DBG("conn %p", conn);
626
627 if (!(conn->hcon->link_mode & HCI_LM_MASTER))
628 return SMP_CMD_NOTSUPP;
629
630 skb_pull(skb, sizeof(*rsp));
631
632 req = (void *) &smp->preq[1];
633
634 key_size = min(req->max_key_size, rsp->max_key_size);
635 if (check_enc_key_size(conn, key_size))
636 return SMP_ENC_KEY_SIZE;
637
638 ret = smp_rand(smp->prnd);
639 if (ret)
640 return SMP_UNSPECIFIED;
641
642 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
643 memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
644
645 if ((req->auth_req & SMP_AUTH_BONDING) &&
646 (rsp->auth_req & SMP_AUTH_BONDING))
647 auth = SMP_AUTH_BONDING;
648
649 auth |= (req->auth_req | rsp->auth_req) & SMP_AUTH_MITM;
650
651 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability);
652 if (ret)
653 return SMP_UNSPECIFIED;
654
655 set_bit(SMP_FLAG_CFM_PENDING, &smp->smp_flags);
656
657 /* Can't compose response until we have been confirmed */
658 if (!test_bit(SMP_FLAG_TK_VALID, &smp->smp_flags))
659 return 0;
660
661 queue_work(hdev->workqueue, &smp->confirm);
662
663 return 0;
664}
665
666static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
667{
668 struct smp_chan *smp = conn->smp_chan;
669 struct hci_dev *hdev = conn->hcon->hdev;
670
671 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
672
673 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
674 skb_pull(skb, sizeof(smp->pcnf));
675
676 if (conn->hcon->out) {
677 u8 random[16];
678
679 swap128(smp->prnd, random);
680 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(random),
681 random);
682 } else if (test_bit(SMP_FLAG_TK_VALID, &smp->smp_flags)) {
683 queue_work(hdev->workqueue, &smp->confirm);
684 } else {
685 set_bit(SMP_FLAG_CFM_PENDING, &smp->smp_flags);
686 }
687
688 return 0;
689}
690
691static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
692{
693 struct smp_chan *smp = conn->smp_chan;
694 struct hci_dev *hdev = conn->hcon->hdev;
695
696 BT_DBG("conn %p", conn);
697
698 swap128(skb->data, smp->rrnd);
699 skb_pull(skb, sizeof(smp->rrnd));
700
701 queue_work(hdev->workqueue, &smp->random);
702
703 return 0;
704}
705
706static u8 smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
707{
708 struct smp_ltk *key;
709 struct hci_conn *hcon = conn->hcon;
710
711 key = hci_find_ltk_by_addr(hcon->hdev, conn->dst, hcon->dst_type);
712 if (!key)
713 return 0;
714
715 if (sec_level > BT_SECURITY_MEDIUM && !key->authenticated)
716 return 0;
717
718 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
719 return 1;
720
721 hci_le_start_enc(hcon, key->ediv, key->rand, key->val);
722 hcon->enc_key_size = key->enc_size;
723
724 return 1;
725
726}
727static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
728{
729 struct smp_cmd_security_req *rp = (void *) skb->data;
730 struct smp_cmd_pairing cp;
731 struct hci_conn *hcon = conn->hcon;
732 struct smp_chan *smp;
733
734 BT_DBG("conn %p", conn);
735
736 hcon->pending_sec_level = authreq_to_seclevel(rp->auth_req);
737
738 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
739 return 0;
740
741 if (test_and_set_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags))
742 return 0;
743
744 smp = smp_chan_create(conn);
745
746 skb_pull(skb, sizeof(*rp));
747
748 memset(&cp, 0, sizeof(cp));
749 build_pairing_cmd(conn, &cp, NULL, rp->auth_req);
750
751 smp->preq[0] = SMP_CMD_PAIRING_REQ;
752 memcpy(&smp->preq[1], &cp, sizeof(cp));
753
754 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
755
756 return 0;
757}
758
759int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
760{
761 struct l2cap_conn *conn = hcon->l2cap_data;
762 struct smp_chan *smp = conn->smp_chan;
763 __u8 authreq;
764
765 BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);
766
767 if (!lmp_host_le_capable(hcon->hdev))
768 return 1;
769
770 if (sec_level == BT_SECURITY_LOW)
771 return 1;
772
773 if (hcon->sec_level >= sec_level)
774 return 1;
775
776 if (hcon->link_mode & HCI_LM_MASTER)
777 if (smp_ltk_encrypt(conn, sec_level))
778 goto done;
779
780 if (test_and_set_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags))
781 return 0;
782
783 smp = smp_chan_create(conn);
784 if (!smp)
785 return 1;
786
787 authreq = seclevel_to_authreq(sec_level);
788
789 if (hcon->link_mode & HCI_LM_MASTER) {
790 struct smp_cmd_pairing cp;
791
792 build_pairing_cmd(conn, &cp, NULL, authreq);
793 smp->preq[0] = SMP_CMD_PAIRING_REQ;
794 memcpy(&smp->preq[1], &cp, sizeof(cp));
795
796 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
797 } else {
798 struct smp_cmd_security_req cp;
799 cp.auth_req = authreq;
800 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
801 }
802
803done:
804 hcon->pending_sec_level = sec_level;
805
806 return 0;
807}
808
809static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb)
810{
811 struct smp_cmd_encrypt_info *rp = (void *) skb->data;
812 struct smp_chan *smp = conn->smp_chan;
813
814 skb_pull(skb, sizeof(*rp));
815
816 memcpy(smp->tk, rp->ltk, sizeof(smp->tk));
817
818 return 0;
819}
820
821static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
822{
823 struct smp_cmd_master_ident *rp = (void *) skb->data;
824 struct smp_chan *smp = conn->smp_chan;
825 struct hci_dev *hdev = conn->hcon->hdev;
826 struct hci_conn *hcon = conn->hcon;
827 u8 authenticated;
828
829 skb_pull(skb, sizeof(*rp));
830
831 hci_dev_lock(hdev);
832 authenticated = (conn->hcon->sec_level == BT_SECURITY_HIGH);
833 hci_add_ltk(conn->hcon->hdev, conn->dst, hcon->dst_type,
834 HCI_SMP_LTK, 1, authenticated, smp->tk, smp->enc_key_size,
835 rp->ediv, rp->rand);
836 smp_distribute_keys(conn, 1);
837 hci_dev_unlock(hdev);
838
839 return 0;
840}
841
842int smp_sig_channel(struct l2cap_conn *conn, struct sk_buff *skb)
843{
844 __u8 code = skb->data[0];
845 __u8 reason;
846 int err = 0;
847
848 if (!lmp_host_le_capable(conn->hcon->hdev)) {
849 err = -ENOTSUPP;
850 reason = SMP_PAIRING_NOTSUPP;
851 goto done;
852 }
853
854 skb_pull(skb, sizeof(code));
855
856 switch (code) {
857 case SMP_CMD_PAIRING_REQ:
858 reason = smp_cmd_pairing_req(conn, skb);
859 break;
860
861 case SMP_CMD_PAIRING_FAIL:
862 smp_failure(conn, skb->data[0], 0);
863 reason = 0;
864 err = -EPERM;
865 break;
866
867 case SMP_CMD_PAIRING_RSP:
868 reason = smp_cmd_pairing_rsp(conn, skb);
869 break;
870
871 case SMP_CMD_SECURITY_REQ:
872 reason = smp_cmd_security_req(conn, skb);
873 break;
874
875 case SMP_CMD_PAIRING_CONFIRM:
876 reason = smp_cmd_pairing_confirm(conn, skb);
877 break;
878
879 case SMP_CMD_PAIRING_RANDOM:
880 reason = smp_cmd_pairing_random(conn, skb);
881 break;
882
883 case SMP_CMD_ENCRYPT_INFO:
884 reason = smp_cmd_encrypt_info(conn, skb);
885 break;
886
887 case SMP_CMD_MASTER_IDENT:
888 reason = smp_cmd_master_ident(conn, skb);
889 break;
890
891 case SMP_CMD_IDENT_INFO:
892 case SMP_CMD_IDENT_ADDR_INFO:
893 case SMP_CMD_SIGN_INFO:
894 /* Just ignored */
895 reason = 0;
896 break;
897
898 default:
899 BT_DBG("Unknown command code 0x%2.2x", code);
900
901 reason = SMP_CMD_NOTSUPP;
902 err = -EOPNOTSUPP;
903 goto done;
904 }
905
906done:
907 if (reason)
908 smp_failure(conn, reason, 1);
909
910 kfree_skb(skb);
911 return err;
912}
913
914int smp_distribute_keys(struct l2cap_conn *conn, __u8 force)
915{
916 struct smp_cmd_pairing *req, *rsp;
917 struct smp_chan *smp = conn->smp_chan;
918 __u8 *keydist;
919
920 BT_DBG("conn %p force %d", conn, force);
921
922 if (!test_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->flags))
923 return 0;
924
925 rsp = (void *) &smp->prsp[1];
926
927 /* The responder sends its keys first */
928 if (!force && conn->hcon->out && (rsp->resp_key_dist & 0x07))
929 return 0;
930
931 req = (void *) &smp->preq[1];
932
933 if (conn->hcon->out) {
934 keydist = &rsp->init_key_dist;
935 *keydist &= req->init_key_dist;
936 } else {
937 keydist = &rsp->resp_key_dist;
938 *keydist &= req->resp_key_dist;
939 }
940
941
942 BT_DBG("keydist 0x%x", *keydist);
943
944 if (*keydist & SMP_DIST_ENC_KEY) {
945 struct smp_cmd_encrypt_info enc;
946 struct smp_cmd_master_ident ident;
947 struct hci_conn *hcon = conn->hcon;
948 u8 authenticated;
949 __le16 ediv;
950
951 get_random_bytes(enc.ltk, sizeof(enc.ltk));
952 get_random_bytes(&ediv, sizeof(ediv));
953 get_random_bytes(ident.rand, sizeof(ident.rand));
954
955 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);
956
957 authenticated = hcon->sec_level == BT_SECURITY_HIGH;
958 hci_add_ltk(conn->hcon->hdev, conn->dst, hcon->dst_type,
959 HCI_SMP_LTK_SLAVE, 1, authenticated,
960 enc.ltk, smp->enc_key_size, ediv, ident.rand);
961
962 ident.ediv = ediv;
963
964 smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident);
965
966 *keydist &= ~SMP_DIST_ENC_KEY;
967 }
968
969 if (*keydist & SMP_DIST_ID_KEY) {
970 struct smp_cmd_ident_addr_info addrinfo;
971 struct smp_cmd_ident_info idinfo;
972
973 /* Send a dummy key */
974 get_random_bytes(idinfo.irk, sizeof(idinfo.irk));
975
976 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);
977
978 /* Just public address */
979 memset(&addrinfo, 0, sizeof(addrinfo));
980 bacpy(&addrinfo.bdaddr, conn->src);
981
982 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo),
983 &addrinfo);
984
985 *keydist &= ~SMP_DIST_ID_KEY;
986 }
987
988 if (*keydist & SMP_DIST_SIGN) {
989 struct smp_cmd_sign_info sign;
990
991 /* Send a dummy key */
992 get_random_bytes(sign.csrk, sizeof(sign.csrk));
993
994 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);
995
996 *keydist &= ~SMP_DIST_SIGN;
997 }
998
999 if (conn->hcon->out || force) {
1000 clear_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->flags);
1001 cancel_delayed_work_sync(&conn->security_timer);
1002 smp_chan_destroy(conn);
1003 }
1004
1005 return 0;
1006}
1/*
2 BlueZ - Bluetooth protocol stack for Linux
3 Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License version 2 as
7 published by the Free Software Foundation;
8
9 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
10 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
11 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
12 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
13 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
14 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17
18 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
19 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
20 SOFTWARE IS DISCLAIMED.
21*/
22
23#include <linux/debugfs.h>
24#include <linux/scatterlist.h>
25#include <linux/crypto.h>
26#include <crypto/b128ops.h>
27#include <crypto/hash.h>
28
29#include <net/bluetooth/bluetooth.h>
30#include <net/bluetooth/hci_core.h>
31#include <net/bluetooth/l2cap.h>
32#include <net/bluetooth/mgmt.h>
33
34#include "ecc.h"
35#include "smp.h"
36
37#define SMP_DEV(hdev) \
38 ((struct smp_dev *)((struct l2cap_chan *)((hdev)->smp_data))->data)
39
40/* Low-level debug macros to be used for stuff that we don't want
41 * accidentially in dmesg, i.e. the values of the various crypto keys
42 * and the inputs & outputs of crypto functions.
43 */
44#ifdef DEBUG
45#define SMP_DBG(fmt, ...) printk(KERN_DEBUG "%s: " fmt, __func__, \
46 ##__VA_ARGS__)
47#else
48#define SMP_DBG(fmt, ...) no_printk(KERN_DEBUG "%s: " fmt, __func__, \
49 ##__VA_ARGS__)
50#endif
51
52#define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd)
53
54/* Keys which are not distributed with Secure Connections */
55#define SMP_SC_NO_DIST (SMP_DIST_ENC_KEY | SMP_DIST_LINK_KEY);
56
57#define SMP_TIMEOUT msecs_to_jiffies(30000)
58
59#define AUTH_REQ_MASK(dev) (hci_dev_test_flag(dev, HCI_SC_ENABLED) ? \
60 0x3f : 0x07)
61#define KEY_DIST_MASK 0x07
62
63/* Maximum message length that can be passed to aes_cmac */
64#define CMAC_MSG_MAX 80
65
66enum {
67 SMP_FLAG_TK_VALID,
68 SMP_FLAG_CFM_PENDING,
69 SMP_FLAG_MITM_AUTH,
70 SMP_FLAG_COMPLETE,
71 SMP_FLAG_INITIATOR,
72 SMP_FLAG_SC,
73 SMP_FLAG_REMOTE_PK,
74 SMP_FLAG_DEBUG_KEY,
75 SMP_FLAG_WAIT_USER,
76 SMP_FLAG_DHKEY_PENDING,
77 SMP_FLAG_REMOTE_OOB,
78 SMP_FLAG_LOCAL_OOB,
79 SMP_FLAG_CT2,
80};
81
82struct smp_dev {
83 /* Secure Connections OOB data */
84 u8 local_pk[64];
85 u8 local_sk[32];
86 u8 local_rand[16];
87 bool debug_key;
88
89 u8 min_key_size;
90 u8 max_key_size;
91
92 struct crypto_cipher *tfm_aes;
93 struct crypto_shash *tfm_cmac;
94};
95
96struct smp_chan {
97 struct l2cap_conn *conn;
98 struct delayed_work security_timer;
99 unsigned long allow_cmd; /* Bitmask of allowed commands */
100
101 u8 preq[7]; /* SMP Pairing Request */
102 u8 prsp[7]; /* SMP Pairing Response */
103 u8 prnd[16]; /* SMP Pairing Random (local) */
104 u8 rrnd[16]; /* SMP Pairing Random (remote) */
105 u8 pcnf[16]; /* SMP Pairing Confirm */
106 u8 tk[16]; /* SMP Temporary Key */
107 u8 rr[16]; /* Remote OOB ra/rb value */
108 u8 lr[16]; /* Local OOB ra/rb value */
109 u8 enc_key_size;
110 u8 remote_key_dist;
111 bdaddr_t id_addr;
112 u8 id_addr_type;
113 u8 irk[16];
114 struct smp_csrk *csrk;
115 struct smp_csrk *slave_csrk;
116 struct smp_ltk *ltk;
117 struct smp_ltk *slave_ltk;
118 struct smp_irk *remote_irk;
119 u8 *link_key;
120 unsigned long flags;
121 u8 method;
122 u8 passkey_round;
123
124 /* Secure Connections variables */
125 u8 local_pk[64];
126 u8 local_sk[32];
127 u8 remote_pk[64];
128 u8 dhkey[32];
129 u8 mackey[16];
130
131 struct crypto_cipher *tfm_aes;
132 struct crypto_shash *tfm_cmac;
133};
134
135/* These debug key values are defined in the SMP section of the core
136 * specification. debug_pk is the public debug key and debug_sk the
137 * private debug key.
138 */
139static const u8 debug_pk[64] = {
140 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
141 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
142 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
143 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20,
144
145 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74,
146 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76,
147 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63,
148 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc,
149};
150
151static const u8 debug_sk[32] = {
152 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58,
153 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a,
154 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74,
155 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f,
156};
157
158static inline void swap_buf(const u8 *src, u8 *dst, size_t len)
159{
160 size_t i;
161
162 for (i = 0; i < len; i++)
163 dst[len - 1 - i] = src[i];
164}
165
166/* The following functions map to the LE SC SMP crypto functions
167 * AES-CMAC, f4, f5, f6, g2 and h6.
168 */
169
170static int aes_cmac(struct crypto_shash *tfm, const u8 k[16], const u8 *m,
171 size_t len, u8 mac[16])
172{
173 uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX];
174 SHASH_DESC_ON_STACK(desc, tfm);
175 int err;
176
177 if (len > CMAC_MSG_MAX)
178 return -EFBIG;
179
180 if (!tfm) {
181 BT_ERR("tfm %p", tfm);
182 return -EINVAL;
183 }
184
185 desc->tfm = tfm;
186 desc->flags = 0;
187
188 /* Swap key and message from LSB to MSB */
189 swap_buf(k, tmp, 16);
190 swap_buf(m, msg_msb, len);
191
192 SMP_DBG("msg (len %zu) %*phN", len, (int) len, m);
193 SMP_DBG("key %16phN", k);
194
195 err = crypto_shash_setkey(tfm, tmp, 16);
196 if (err) {
197 BT_ERR("cipher setkey failed: %d", err);
198 return err;
199 }
200
201 err = crypto_shash_digest(desc, msg_msb, len, mac_msb);
202 shash_desc_zero(desc);
203 if (err) {
204 BT_ERR("Hash computation error %d", err);
205 return err;
206 }
207
208 swap_buf(mac_msb, mac, 16);
209
210 SMP_DBG("mac %16phN", mac);
211
212 return 0;
213}
214
215static int smp_f4(struct crypto_shash *tfm_cmac, const u8 u[32],
216 const u8 v[32], const u8 x[16], u8 z, u8 res[16])
217{
218 u8 m[65];
219 int err;
220
221 SMP_DBG("u %32phN", u);
222 SMP_DBG("v %32phN", v);
223 SMP_DBG("x %16phN z %02x", x, z);
224
225 m[0] = z;
226 memcpy(m + 1, v, 32);
227 memcpy(m + 33, u, 32);
228
229 err = aes_cmac(tfm_cmac, x, m, sizeof(m), res);
230 if (err)
231 return err;
232
233 SMP_DBG("res %16phN", res);
234
235 return err;
236}
237
238static int smp_f5(struct crypto_shash *tfm_cmac, const u8 w[32],
239 const u8 n1[16], const u8 n2[16], const u8 a1[7],
240 const u8 a2[7], u8 mackey[16], u8 ltk[16])
241{
242 /* The btle, salt and length "magic" values are as defined in
243 * the SMP section of the Bluetooth core specification. In ASCII
244 * the btle value ends up being 'btle'. The salt is just a
245 * random number whereas length is the value 256 in little
246 * endian format.
247 */
248 const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 };
249 const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60,
250 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c };
251 const u8 length[2] = { 0x00, 0x01 };
252 u8 m[53], t[16];
253 int err;
254
255 SMP_DBG("w %32phN", w);
256 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
257 SMP_DBG("a1 %7phN a2 %7phN", a1, a2);
258
259 err = aes_cmac(tfm_cmac, salt, w, 32, t);
260 if (err)
261 return err;
262
263 SMP_DBG("t %16phN", t);
264
265 memcpy(m, length, 2);
266 memcpy(m + 2, a2, 7);
267 memcpy(m + 9, a1, 7);
268 memcpy(m + 16, n2, 16);
269 memcpy(m + 32, n1, 16);
270 memcpy(m + 48, btle, 4);
271
272 m[52] = 0; /* Counter */
273
274 err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey);
275 if (err)
276 return err;
277
278 SMP_DBG("mackey %16phN", mackey);
279
280 m[52] = 1; /* Counter */
281
282 err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk);
283 if (err)
284 return err;
285
286 SMP_DBG("ltk %16phN", ltk);
287
288 return 0;
289}
290
291static int smp_f6(struct crypto_shash *tfm_cmac, const u8 w[16],
292 const u8 n1[16], const u8 n2[16], const u8 r[16],
293 const u8 io_cap[3], const u8 a1[7], const u8 a2[7],
294 u8 res[16])
295{
296 u8 m[65];
297 int err;
298
299 SMP_DBG("w %16phN", w);
300 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
301 SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2);
302
303 memcpy(m, a2, 7);
304 memcpy(m + 7, a1, 7);
305 memcpy(m + 14, io_cap, 3);
306 memcpy(m + 17, r, 16);
307 memcpy(m + 33, n2, 16);
308 memcpy(m + 49, n1, 16);
309
310 err = aes_cmac(tfm_cmac, w, m, sizeof(m), res);
311 if (err)
312 return err;
313
314 SMP_DBG("res %16phN", res);
315
316 return err;
317}
318
319static int smp_g2(struct crypto_shash *tfm_cmac, const u8 u[32], const u8 v[32],
320 const u8 x[16], const u8 y[16], u32 *val)
321{
322 u8 m[80], tmp[16];
323 int err;
324
325 SMP_DBG("u %32phN", u);
326 SMP_DBG("v %32phN", v);
327 SMP_DBG("x %16phN y %16phN", x, y);
328
329 memcpy(m, y, 16);
330 memcpy(m + 16, v, 32);
331 memcpy(m + 48, u, 32);
332
333 err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp);
334 if (err)
335 return err;
336
337 *val = get_unaligned_le32(tmp);
338 *val %= 1000000;
339
340 SMP_DBG("val %06u", *val);
341
342 return 0;
343}
344
345static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16],
346 const u8 key_id[4], u8 res[16])
347{
348 int err;
349
350 SMP_DBG("w %16phN key_id %4phN", w, key_id);
351
352 err = aes_cmac(tfm_cmac, w, key_id, 4, res);
353 if (err)
354 return err;
355
356 SMP_DBG("res %16phN", res);
357
358 return err;
359}
360
361static int smp_h7(struct crypto_shash *tfm_cmac, const u8 w[16],
362 const u8 salt[16], u8 res[16])
363{
364 int err;
365
366 SMP_DBG("w %16phN salt %16phN", w, salt);
367
368 err = aes_cmac(tfm_cmac, salt, w, 16, res);
369 if (err)
370 return err;
371
372 SMP_DBG("res %16phN", res);
373
374 return err;
375}
376
377/* The following functions map to the legacy SMP crypto functions e, c1,
378 * s1 and ah.
379 */
380
381static int smp_e(struct crypto_cipher *tfm, const u8 *k, u8 *r)
382{
383 uint8_t tmp[16], data[16];
384 int err;
385
386 SMP_DBG("k %16phN r %16phN", k, r);
387
388 if (!tfm) {
389 BT_ERR("tfm %p", tfm);
390 return -EINVAL;
391 }
392
393 /* The most significant octet of key corresponds to k[0] */
394 swap_buf(k, tmp, 16);
395
396 err = crypto_cipher_setkey(tfm, tmp, 16);
397 if (err) {
398 BT_ERR("cipher setkey failed: %d", err);
399 return err;
400 }
401
402 /* Most significant octet of plaintextData corresponds to data[0] */
403 swap_buf(r, data, 16);
404
405 crypto_cipher_encrypt_one(tfm, data, data);
406
407 /* Most significant octet of encryptedData corresponds to data[0] */
408 swap_buf(data, r, 16);
409
410 SMP_DBG("r %16phN", r);
411
412 return err;
413}
414
415static int smp_c1(struct crypto_cipher *tfm_aes, const u8 k[16],
416 const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat,
417 const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16])
418{
419 u8 p1[16], p2[16];
420 int err;
421
422 SMP_DBG("k %16phN r %16phN", k, r);
423 SMP_DBG("iat %u ia %6phN rat %u ra %6phN", _iat, ia, _rat, ra);
424 SMP_DBG("preq %7phN pres %7phN", preq, pres);
425
426 memset(p1, 0, 16);
427
428 /* p1 = pres || preq || _rat || _iat */
429 p1[0] = _iat;
430 p1[1] = _rat;
431 memcpy(p1 + 2, preq, 7);
432 memcpy(p1 + 9, pres, 7);
433
434 SMP_DBG("p1 %16phN", p1);
435
436 /* res = r XOR p1 */
437 u128_xor((u128 *) res, (u128 *) r, (u128 *) p1);
438
439 /* res = e(k, res) */
440 err = smp_e(tfm_aes, k, res);
441 if (err) {
442 BT_ERR("Encrypt data error");
443 return err;
444 }
445
446 /* p2 = padding || ia || ra */
447 memcpy(p2, ra, 6);
448 memcpy(p2 + 6, ia, 6);
449 memset(p2 + 12, 0, 4);
450
451 SMP_DBG("p2 %16phN", p2);
452
453 /* res = res XOR p2 */
454 u128_xor((u128 *) res, (u128 *) res, (u128 *) p2);
455
456 /* res = e(k, res) */
457 err = smp_e(tfm_aes, k, res);
458 if (err)
459 BT_ERR("Encrypt data error");
460
461 return err;
462}
463
464static int smp_s1(struct crypto_cipher *tfm_aes, const u8 k[16],
465 const u8 r1[16], const u8 r2[16], u8 _r[16])
466{
467 int err;
468
469 /* Just least significant octets from r1 and r2 are considered */
470 memcpy(_r, r2, 8);
471 memcpy(_r + 8, r1, 8);
472
473 err = smp_e(tfm_aes, k, _r);
474 if (err)
475 BT_ERR("Encrypt data error");
476
477 return err;
478}
479
480static int smp_ah(struct crypto_cipher *tfm, const u8 irk[16],
481 const u8 r[3], u8 res[3])
482{
483 u8 _res[16];
484 int err;
485
486 /* r' = padding || r */
487 memcpy(_res, r, 3);
488 memset(_res + 3, 0, 13);
489
490 err = smp_e(tfm, irk, _res);
491 if (err) {
492 BT_ERR("Encrypt error");
493 return err;
494 }
495
496 /* The output of the random address function ah is:
497 * ah(k, r) = e(k, r') mod 2^24
498 * The output of the security function e is then truncated to 24 bits
499 * by taking the least significant 24 bits of the output of e as the
500 * result of ah.
501 */
502 memcpy(res, _res, 3);
503
504 return 0;
505}
506
507bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16],
508 const bdaddr_t *bdaddr)
509{
510 struct l2cap_chan *chan = hdev->smp_data;
511 struct smp_dev *smp;
512 u8 hash[3];
513 int err;
514
515 if (!chan || !chan->data)
516 return false;
517
518 smp = chan->data;
519
520 BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk);
521
522 err = smp_ah(smp->tfm_aes, irk, &bdaddr->b[3], hash);
523 if (err)
524 return false;
525
526 return !memcmp(bdaddr->b, hash, 3);
527}
528
529int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa)
530{
531 struct l2cap_chan *chan = hdev->smp_data;
532 struct smp_dev *smp;
533 int err;
534
535 if (!chan || !chan->data)
536 return -EOPNOTSUPP;
537
538 smp = chan->data;
539
540 get_random_bytes(&rpa->b[3], 3);
541
542 rpa->b[5] &= 0x3f; /* Clear two most significant bits */
543 rpa->b[5] |= 0x40; /* Set second most significant bit */
544
545 err = smp_ah(smp->tfm_aes, irk, &rpa->b[3], rpa->b);
546 if (err < 0)
547 return err;
548
549 BT_DBG("RPA %pMR", rpa);
550
551 return 0;
552}
553
554int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16])
555{
556 struct l2cap_chan *chan = hdev->smp_data;
557 struct smp_dev *smp;
558 int err;
559
560 if (!chan || !chan->data)
561 return -EOPNOTSUPP;
562
563 smp = chan->data;
564
565 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
566 BT_DBG("Using debug keys");
567 memcpy(smp->local_pk, debug_pk, 64);
568 memcpy(smp->local_sk, debug_sk, 32);
569 smp->debug_key = true;
570 } else {
571 while (true) {
572 /* Generate local key pair for Secure Connections */
573 if (!ecc_make_key(smp->local_pk, smp->local_sk))
574 return -EIO;
575
576 /* This is unlikely, but we need to check that
577 * we didn't accidentially generate a debug key.
578 */
579 if (memcmp(smp->local_sk, debug_sk, 32))
580 break;
581 }
582 smp->debug_key = false;
583 }
584
585 SMP_DBG("OOB Public Key X: %32phN", smp->local_pk);
586 SMP_DBG("OOB Public Key Y: %32phN", smp->local_pk + 32);
587 SMP_DBG("OOB Private Key: %32phN", smp->local_sk);
588
589 get_random_bytes(smp->local_rand, 16);
590
591 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->local_pk,
592 smp->local_rand, 0, hash);
593 if (err < 0)
594 return err;
595
596 memcpy(rand, smp->local_rand, 16);
597
598 return 0;
599}
600
601static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
602{
603 struct l2cap_chan *chan = conn->smp;
604 struct smp_chan *smp;
605 struct kvec iv[2];
606 struct msghdr msg;
607
608 if (!chan)
609 return;
610
611 BT_DBG("code 0x%2.2x", code);
612
613 iv[0].iov_base = &code;
614 iv[0].iov_len = 1;
615
616 iv[1].iov_base = data;
617 iv[1].iov_len = len;
618
619 memset(&msg, 0, sizeof(msg));
620
621 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iv, 2, 1 + len);
622
623 l2cap_chan_send(chan, &msg, 1 + len);
624
625 if (!chan->data)
626 return;
627
628 smp = chan->data;
629
630 cancel_delayed_work_sync(&smp->security_timer);
631 schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT);
632}
633
634static u8 authreq_to_seclevel(u8 authreq)
635{
636 if (authreq & SMP_AUTH_MITM) {
637 if (authreq & SMP_AUTH_SC)
638 return BT_SECURITY_FIPS;
639 else
640 return BT_SECURITY_HIGH;
641 } else {
642 return BT_SECURITY_MEDIUM;
643 }
644}
645
646static __u8 seclevel_to_authreq(__u8 sec_level)
647{
648 switch (sec_level) {
649 case BT_SECURITY_FIPS:
650 case BT_SECURITY_HIGH:
651 return SMP_AUTH_MITM | SMP_AUTH_BONDING;
652 case BT_SECURITY_MEDIUM:
653 return SMP_AUTH_BONDING;
654 default:
655 return SMP_AUTH_NONE;
656 }
657}
658
659static void build_pairing_cmd(struct l2cap_conn *conn,
660 struct smp_cmd_pairing *req,
661 struct smp_cmd_pairing *rsp, __u8 authreq)
662{
663 struct l2cap_chan *chan = conn->smp;
664 struct smp_chan *smp = chan->data;
665 struct hci_conn *hcon = conn->hcon;
666 struct hci_dev *hdev = hcon->hdev;
667 u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT;
668
669 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
670 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
671 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
672 authreq |= SMP_AUTH_BONDING;
673 } else {
674 authreq &= ~SMP_AUTH_BONDING;
675 }
676
677 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
678 remote_dist |= SMP_DIST_ID_KEY;
679
680 if (hci_dev_test_flag(hdev, HCI_PRIVACY))
681 local_dist |= SMP_DIST_ID_KEY;
682
683 if (hci_dev_test_flag(hdev, HCI_SC_ENABLED) &&
684 (authreq & SMP_AUTH_SC)) {
685 struct oob_data *oob_data;
686 u8 bdaddr_type;
687
688 if (hci_dev_test_flag(hdev, HCI_SSP_ENABLED)) {
689 local_dist |= SMP_DIST_LINK_KEY;
690 remote_dist |= SMP_DIST_LINK_KEY;
691 }
692
693 if (hcon->dst_type == ADDR_LE_DEV_PUBLIC)
694 bdaddr_type = BDADDR_LE_PUBLIC;
695 else
696 bdaddr_type = BDADDR_LE_RANDOM;
697
698 oob_data = hci_find_remote_oob_data(hdev, &hcon->dst,
699 bdaddr_type);
700 if (oob_data && oob_data->present) {
701 set_bit(SMP_FLAG_REMOTE_OOB, &smp->flags);
702 oob_flag = SMP_OOB_PRESENT;
703 memcpy(smp->rr, oob_data->rand256, 16);
704 memcpy(smp->pcnf, oob_data->hash256, 16);
705 SMP_DBG("OOB Remote Confirmation: %16phN", smp->pcnf);
706 SMP_DBG("OOB Remote Random: %16phN", smp->rr);
707 }
708
709 } else {
710 authreq &= ~SMP_AUTH_SC;
711 }
712
713 if (rsp == NULL) {
714 req->io_capability = conn->hcon->io_capability;
715 req->oob_flag = oob_flag;
716 req->max_key_size = SMP_DEV(hdev)->max_key_size;
717 req->init_key_dist = local_dist;
718 req->resp_key_dist = remote_dist;
719 req->auth_req = (authreq & AUTH_REQ_MASK(hdev));
720
721 smp->remote_key_dist = remote_dist;
722 return;
723 }
724
725 rsp->io_capability = conn->hcon->io_capability;
726 rsp->oob_flag = oob_flag;
727 rsp->max_key_size = SMP_DEV(hdev)->max_key_size;
728 rsp->init_key_dist = req->init_key_dist & remote_dist;
729 rsp->resp_key_dist = req->resp_key_dist & local_dist;
730 rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev));
731
732 smp->remote_key_dist = rsp->init_key_dist;
733}
734
735static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)
736{
737 struct l2cap_chan *chan = conn->smp;
738 struct hci_dev *hdev = conn->hcon->hdev;
739 struct smp_chan *smp = chan->data;
740
741 if (max_key_size > SMP_DEV(hdev)->max_key_size ||
742 max_key_size < SMP_MIN_ENC_KEY_SIZE)
743 return SMP_ENC_KEY_SIZE;
744
745 smp->enc_key_size = max_key_size;
746
747 return 0;
748}
749
750static void smp_chan_destroy(struct l2cap_conn *conn)
751{
752 struct l2cap_chan *chan = conn->smp;
753 struct smp_chan *smp = chan->data;
754 struct hci_conn *hcon = conn->hcon;
755 bool complete;
756
757 BUG_ON(!smp);
758
759 cancel_delayed_work_sync(&smp->security_timer);
760
761 complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags);
762 mgmt_smp_complete(hcon, complete);
763
764 kzfree(smp->csrk);
765 kzfree(smp->slave_csrk);
766 kzfree(smp->link_key);
767
768 crypto_free_cipher(smp->tfm_aes);
769 crypto_free_shash(smp->tfm_cmac);
770
771 /* Ensure that we don't leave any debug key around if debug key
772 * support hasn't been explicitly enabled.
773 */
774 if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG &&
775 !hci_dev_test_flag(hcon->hdev, HCI_KEEP_DEBUG_KEYS)) {
776 list_del_rcu(&smp->ltk->list);
777 kfree_rcu(smp->ltk, rcu);
778 smp->ltk = NULL;
779 }
780
781 /* If pairing failed clean up any keys we might have */
782 if (!complete) {
783 if (smp->ltk) {
784 list_del_rcu(&smp->ltk->list);
785 kfree_rcu(smp->ltk, rcu);
786 }
787
788 if (smp->slave_ltk) {
789 list_del_rcu(&smp->slave_ltk->list);
790 kfree_rcu(smp->slave_ltk, rcu);
791 }
792
793 if (smp->remote_irk) {
794 list_del_rcu(&smp->remote_irk->list);
795 kfree_rcu(smp->remote_irk, rcu);
796 }
797 }
798
799 chan->data = NULL;
800 kzfree(smp);
801 hci_conn_drop(hcon);
802}
803
804static void smp_failure(struct l2cap_conn *conn, u8 reason)
805{
806 struct hci_conn *hcon = conn->hcon;
807 struct l2cap_chan *chan = conn->smp;
808
809 if (reason)
810 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
811 &reason);
812
813 mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE);
814
815 if (chan->data)
816 smp_chan_destroy(conn);
817}
818
819#define JUST_WORKS 0x00
820#define JUST_CFM 0x01
821#define REQ_PASSKEY 0x02
822#define CFM_PASSKEY 0x03
823#define REQ_OOB 0x04
824#define DSP_PASSKEY 0x05
825#define OVERLAP 0xFF
826
827static const u8 gen_method[5][5] = {
828 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
829 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
830 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
831 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
832 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP },
833};
834
835static const u8 sc_method[5][5] = {
836 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
837 { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
838 { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY },
839 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
840 { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
841};
842
843static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io)
844{
845 /* If either side has unknown io_caps, use JUST_CFM (which gets
846 * converted later to JUST_WORKS if we're initiators.
847 */
848 if (local_io > SMP_IO_KEYBOARD_DISPLAY ||
849 remote_io > SMP_IO_KEYBOARD_DISPLAY)
850 return JUST_CFM;
851
852 if (test_bit(SMP_FLAG_SC, &smp->flags))
853 return sc_method[remote_io][local_io];
854
855 return gen_method[remote_io][local_io];
856}
857
858static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
859 u8 local_io, u8 remote_io)
860{
861 struct hci_conn *hcon = conn->hcon;
862 struct l2cap_chan *chan = conn->smp;
863 struct smp_chan *smp = chan->data;
864 u32 passkey = 0;
865 int ret = 0;
866
867 /* Initialize key for JUST WORKS */
868 memset(smp->tk, 0, sizeof(smp->tk));
869 clear_bit(SMP_FLAG_TK_VALID, &smp->flags);
870
871 BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io);
872
873 /* If neither side wants MITM, either "just" confirm an incoming
874 * request or use just-works for outgoing ones. The JUST_CFM
875 * will be converted to JUST_WORKS if necessary later in this
876 * function. If either side has MITM look up the method from the
877 * table.
878 */
879 if (!(auth & SMP_AUTH_MITM))
880 smp->method = JUST_CFM;
881 else
882 smp->method = get_auth_method(smp, local_io, remote_io);
883
884 /* Don't confirm locally initiated pairing attempts */
885 if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR,
886 &smp->flags))
887 smp->method = JUST_WORKS;
888
889 /* Don't bother user space with no IO capabilities */
890 if (smp->method == JUST_CFM &&
891 hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
892 smp->method = JUST_WORKS;
893
894 /* If Just Works, Continue with Zero TK */
895 if (smp->method == JUST_WORKS) {
896 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
897 return 0;
898 }
899
900 /* If this function is used for SC -> legacy fallback we
901 * can only recover the just-works case.
902 */
903 if (test_bit(SMP_FLAG_SC, &smp->flags))
904 return -EINVAL;
905
906 /* Not Just Works/Confirm results in MITM Authentication */
907 if (smp->method != JUST_CFM) {
908 set_bit(SMP_FLAG_MITM_AUTH, &smp->flags);
909 if (hcon->pending_sec_level < BT_SECURITY_HIGH)
910 hcon->pending_sec_level = BT_SECURITY_HIGH;
911 }
912
913 /* If both devices have Keyoard-Display I/O, the master
914 * Confirms and the slave Enters the passkey.
915 */
916 if (smp->method == OVERLAP) {
917 if (hcon->role == HCI_ROLE_MASTER)
918 smp->method = CFM_PASSKEY;
919 else
920 smp->method = REQ_PASSKEY;
921 }
922
923 /* Generate random passkey. */
924 if (smp->method == CFM_PASSKEY) {
925 memset(smp->tk, 0, sizeof(smp->tk));
926 get_random_bytes(&passkey, sizeof(passkey));
927 passkey %= 1000000;
928 put_unaligned_le32(passkey, smp->tk);
929 BT_DBG("PassKey: %d", passkey);
930 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
931 }
932
933 if (smp->method == REQ_PASSKEY)
934 ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst,
935 hcon->type, hcon->dst_type);
936 else if (smp->method == JUST_CFM)
937 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
938 hcon->type, hcon->dst_type,
939 passkey, 1);
940 else
941 ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst,
942 hcon->type, hcon->dst_type,
943 passkey, 0);
944
945 return ret;
946}
947
948static u8 smp_confirm(struct smp_chan *smp)
949{
950 struct l2cap_conn *conn = smp->conn;
951 struct smp_cmd_pairing_confirm cp;
952 int ret;
953
954 BT_DBG("conn %p", conn);
955
956 ret = smp_c1(smp->tfm_aes, smp->tk, smp->prnd, smp->preq, smp->prsp,
957 conn->hcon->init_addr_type, &conn->hcon->init_addr,
958 conn->hcon->resp_addr_type, &conn->hcon->resp_addr,
959 cp.confirm_val);
960 if (ret)
961 return SMP_UNSPECIFIED;
962
963 clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
964
965 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
966
967 if (conn->hcon->out)
968 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
969 else
970 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
971
972 return 0;
973}
974
975static u8 smp_random(struct smp_chan *smp)
976{
977 struct l2cap_conn *conn = smp->conn;
978 struct hci_conn *hcon = conn->hcon;
979 u8 confirm[16];
980 int ret;
981
982 if (IS_ERR_OR_NULL(smp->tfm_aes))
983 return SMP_UNSPECIFIED;
984
985 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
986
987 ret = smp_c1(smp->tfm_aes, smp->tk, smp->rrnd, smp->preq, smp->prsp,
988 hcon->init_addr_type, &hcon->init_addr,
989 hcon->resp_addr_type, &hcon->resp_addr, confirm);
990 if (ret)
991 return SMP_UNSPECIFIED;
992
993 if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) {
994 BT_ERR("Pairing failed (confirmation values mismatch)");
995 return SMP_CONFIRM_FAILED;
996 }
997
998 if (hcon->out) {
999 u8 stk[16];
1000 __le64 rand = 0;
1001 __le16 ediv = 0;
1002
1003 smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk);
1004
1005 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
1006 return SMP_UNSPECIFIED;
1007
1008 hci_le_start_enc(hcon, ediv, rand, stk, smp->enc_key_size);
1009 hcon->enc_key_size = smp->enc_key_size;
1010 set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
1011 } else {
1012 u8 stk[16], auth;
1013 __le64 rand = 0;
1014 __le16 ediv = 0;
1015
1016 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1017 smp->prnd);
1018
1019 smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk);
1020
1021 if (hcon->pending_sec_level == BT_SECURITY_HIGH)
1022 auth = 1;
1023 else
1024 auth = 0;
1025
1026 /* Even though there's no _SLAVE suffix this is the
1027 * slave STK we're adding for later lookup (the master
1028 * STK never needs to be stored).
1029 */
1030 hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1031 SMP_STK, auth, stk, smp->enc_key_size, ediv, rand);
1032 }
1033
1034 return 0;
1035}
1036
1037static void smp_notify_keys(struct l2cap_conn *conn)
1038{
1039 struct l2cap_chan *chan = conn->smp;
1040 struct smp_chan *smp = chan->data;
1041 struct hci_conn *hcon = conn->hcon;
1042 struct hci_dev *hdev = hcon->hdev;
1043 struct smp_cmd_pairing *req = (void *) &smp->preq[1];
1044 struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1];
1045 bool persistent;
1046
1047 if (hcon->type == ACL_LINK) {
1048 if (hcon->key_type == HCI_LK_DEBUG_COMBINATION)
1049 persistent = false;
1050 else
1051 persistent = !test_bit(HCI_CONN_FLUSH_KEY,
1052 &hcon->flags);
1053 } else {
1054 /* The LTKs, IRKs and CSRKs should be persistent only if
1055 * both sides had the bonding bit set in their
1056 * authentication requests.
1057 */
1058 persistent = !!((req->auth_req & rsp->auth_req) &
1059 SMP_AUTH_BONDING);
1060 }
1061
1062 if (smp->remote_irk) {
1063 mgmt_new_irk(hdev, smp->remote_irk, persistent);
1064
1065 /* Now that user space can be considered to know the
1066 * identity address track the connection based on it
1067 * from now on (assuming this is an LE link).
1068 */
1069 if (hcon->type == LE_LINK) {
1070 bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
1071 hcon->dst_type = smp->remote_irk->addr_type;
1072 queue_work(hdev->workqueue, &conn->id_addr_update_work);
1073 }
1074 }
1075
1076 if (smp->csrk) {
1077 smp->csrk->bdaddr_type = hcon->dst_type;
1078 bacpy(&smp->csrk->bdaddr, &hcon->dst);
1079 mgmt_new_csrk(hdev, smp->csrk, persistent);
1080 }
1081
1082 if (smp->slave_csrk) {
1083 smp->slave_csrk->bdaddr_type = hcon->dst_type;
1084 bacpy(&smp->slave_csrk->bdaddr, &hcon->dst);
1085 mgmt_new_csrk(hdev, smp->slave_csrk, persistent);
1086 }
1087
1088 if (smp->ltk) {
1089 smp->ltk->bdaddr_type = hcon->dst_type;
1090 bacpy(&smp->ltk->bdaddr, &hcon->dst);
1091 mgmt_new_ltk(hdev, smp->ltk, persistent);
1092 }
1093
1094 if (smp->slave_ltk) {
1095 smp->slave_ltk->bdaddr_type = hcon->dst_type;
1096 bacpy(&smp->slave_ltk->bdaddr, &hcon->dst);
1097 mgmt_new_ltk(hdev, smp->slave_ltk, persistent);
1098 }
1099
1100 if (smp->link_key) {
1101 struct link_key *key;
1102 u8 type;
1103
1104 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1105 type = HCI_LK_DEBUG_COMBINATION;
1106 else if (hcon->sec_level == BT_SECURITY_FIPS)
1107 type = HCI_LK_AUTH_COMBINATION_P256;
1108 else
1109 type = HCI_LK_UNAUTH_COMBINATION_P256;
1110
1111 key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst,
1112 smp->link_key, type, 0, &persistent);
1113 if (key) {
1114 mgmt_new_link_key(hdev, key, persistent);
1115
1116 /* Don't keep debug keys around if the relevant
1117 * flag is not set.
1118 */
1119 if (!hci_dev_test_flag(hdev, HCI_KEEP_DEBUG_KEYS) &&
1120 key->type == HCI_LK_DEBUG_COMBINATION) {
1121 list_del_rcu(&key->list);
1122 kfree_rcu(key, rcu);
1123 }
1124 }
1125 }
1126}
1127
1128static void sc_add_ltk(struct smp_chan *smp)
1129{
1130 struct hci_conn *hcon = smp->conn->hcon;
1131 u8 key_type, auth;
1132
1133 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1134 key_type = SMP_LTK_P256_DEBUG;
1135 else
1136 key_type = SMP_LTK_P256;
1137
1138 if (hcon->pending_sec_level == BT_SECURITY_FIPS)
1139 auth = 1;
1140 else
1141 auth = 0;
1142
1143 smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1144 key_type, auth, smp->tk, smp->enc_key_size,
1145 0, 0);
1146}
1147
1148static void sc_generate_link_key(struct smp_chan *smp)
1149{
1150 /* From core spec. Spells out in ASCII as 'lebr'. */
1151 const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c };
1152
1153 smp->link_key = kzalloc(16, GFP_KERNEL);
1154 if (!smp->link_key)
1155 return;
1156
1157 if (test_bit(SMP_FLAG_CT2, &smp->flags)) {
1158 /* SALT = 0x00000000000000000000000000000000746D7031 */
1159 const u8 salt[16] = { 0x31, 0x70, 0x6d, 0x74 };
1160
1161 if (smp_h7(smp->tfm_cmac, smp->tk, salt, smp->link_key)) {
1162 kzfree(smp->link_key);
1163 smp->link_key = NULL;
1164 return;
1165 }
1166 } else {
1167 /* From core spec. Spells out in ASCII as 'tmp1'. */
1168 const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 };
1169
1170 if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) {
1171 kzfree(smp->link_key);
1172 smp->link_key = NULL;
1173 return;
1174 }
1175 }
1176
1177 if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) {
1178 kzfree(smp->link_key);
1179 smp->link_key = NULL;
1180 return;
1181 }
1182}
1183
1184static void smp_allow_key_dist(struct smp_chan *smp)
1185{
1186 /* Allow the first expected phase 3 PDU. The rest of the PDUs
1187 * will be allowed in each PDU handler to ensure we receive
1188 * them in the correct order.
1189 */
1190 if (smp->remote_key_dist & SMP_DIST_ENC_KEY)
1191 SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO);
1192 else if (smp->remote_key_dist & SMP_DIST_ID_KEY)
1193 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
1194 else if (smp->remote_key_dist & SMP_DIST_SIGN)
1195 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
1196}
1197
1198static void sc_generate_ltk(struct smp_chan *smp)
1199{
1200 /* From core spec. Spells out in ASCII as 'brle'. */
1201 const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 };
1202 struct hci_conn *hcon = smp->conn->hcon;
1203 struct hci_dev *hdev = hcon->hdev;
1204 struct link_key *key;
1205
1206 key = hci_find_link_key(hdev, &hcon->dst);
1207 if (!key) {
1208 BT_ERR("%s No Link Key found to generate LTK", hdev->name);
1209 return;
1210 }
1211
1212 if (key->type == HCI_LK_DEBUG_COMBINATION)
1213 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1214
1215 if (test_bit(SMP_FLAG_CT2, &smp->flags)) {
1216 /* SALT = 0x00000000000000000000000000000000746D7032 */
1217 const u8 salt[16] = { 0x32, 0x70, 0x6d, 0x74 };
1218
1219 if (smp_h7(smp->tfm_cmac, key->val, salt, smp->tk))
1220 return;
1221 } else {
1222 /* From core spec. Spells out in ASCII as 'tmp2'. */
1223 const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 };
1224
1225 if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk))
1226 return;
1227 }
1228
1229 if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk))
1230 return;
1231
1232 sc_add_ltk(smp);
1233}
1234
1235static void smp_distribute_keys(struct smp_chan *smp)
1236{
1237 struct smp_cmd_pairing *req, *rsp;
1238 struct l2cap_conn *conn = smp->conn;
1239 struct hci_conn *hcon = conn->hcon;
1240 struct hci_dev *hdev = hcon->hdev;
1241 __u8 *keydist;
1242
1243 BT_DBG("conn %p", conn);
1244
1245 rsp = (void *) &smp->prsp[1];
1246
1247 /* The responder sends its keys first */
1248 if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) {
1249 smp_allow_key_dist(smp);
1250 return;
1251 }
1252
1253 req = (void *) &smp->preq[1];
1254
1255 if (hcon->out) {
1256 keydist = &rsp->init_key_dist;
1257 *keydist &= req->init_key_dist;
1258 } else {
1259 keydist = &rsp->resp_key_dist;
1260 *keydist &= req->resp_key_dist;
1261 }
1262
1263 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1264 if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY))
1265 sc_generate_link_key(smp);
1266 if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY))
1267 sc_generate_ltk(smp);
1268
1269 /* Clear the keys which are generated but not distributed */
1270 *keydist &= ~SMP_SC_NO_DIST;
1271 }
1272
1273 BT_DBG("keydist 0x%x", *keydist);
1274
1275 if (*keydist & SMP_DIST_ENC_KEY) {
1276 struct smp_cmd_encrypt_info enc;
1277 struct smp_cmd_master_ident ident;
1278 struct smp_ltk *ltk;
1279 u8 authenticated;
1280 __le16 ediv;
1281 __le64 rand;
1282
1283 /* Make sure we generate only the significant amount of
1284 * bytes based on the encryption key size, and set the rest
1285 * of the value to zeroes.
1286 */
1287 get_random_bytes(enc.ltk, smp->enc_key_size);
1288 memset(enc.ltk + smp->enc_key_size, 0,
1289 sizeof(enc.ltk) - smp->enc_key_size);
1290
1291 get_random_bytes(&ediv, sizeof(ediv));
1292 get_random_bytes(&rand, sizeof(rand));
1293
1294 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);
1295
1296 authenticated = hcon->sec_level == BT_SECURITY_HIGH;
1297 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type,
1298 SMP_LTK_SLAVE, authenticated, enc.ltk,
1299 smp->enc_key_size, ediv, rand);
1300 smp->slave_ltk = ltk;
1301
1302 ident.ediv = ediv;
1303 ident.rand = rand;
1304
1305 smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident);
1306
1307 *keydist &= ~SMP_DIST_ENC_KEY;
1308 }
1309
1310 if (*keydist & SMP_DIST_ID_KEY) {
1311 struct smp_cmd_ident_addr_info addrinfo;
1312 struct smp_cmd_ident_info idinfo;
1313
1314 memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk));
1315
1316 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);
1317
1318 /* The hci_conn contains the local identity address
1319 * after the connection has been established.
1320 *
1321 * This is true even when the connection has been
1322 * established using a resolvable random address.
1323 */
1324 bacpy(&addrinfo.bdaddr, &hcon->src);
1325 addrinfo.addr_type = hcon->src_type;
1326
1327 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo),
1328 &addrinfo);
1329
1330 *keydist &= ~SMP_DIST_ID_KEY;
1331 }
1332
1333 if (*keydist & SMP_DIST_SIGN) {
1334 struct smp_cmd_sign_info sign;
1335 struct smp_csrk *csrk;
1336
1337 /* Generate a new random key */
1338 get_random_bytes(sign.csrk, sizeof(sign.csrk));
1339
1340 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
1341 if (csrk) {
1342 if (hcon->sec_level > BT_SECURITY_MEDIUM)
1343 csrk->type = MGMT_CSRK_LOCAL_AUTHENTICATED;
1344 else
1345 csrk->type = MGMT_CSRK_LOCAL_UNAUTHENTICATED;
1346 memcpy(csrk->val, sign.csrk, sizeof(csrk->val));
1347 }
1348 smp->slave_csrk = csrk;
1349
1350 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);
1351
1352 *keydist &= ~SMP_DIST_SIGN;
1353 }
1354
1355 /* If there are still keys to be received wait for them */
1356 if (smp->remote_key_dist & KEY_DIST_MASK) {
1357 smp_allow_key_dist(smp);
1358 return;
1359 }
1360
1361 set_bit(SMP_FLAG_COMPLETE, &smp->flags);
1362 smp_notify_keys(conn);
1363
1364 smp_chan_destroy(conn);
1365}
1366
1367static void smp_timeout(struct work_struct *work)
1368{
1369 struct smp_chan *smp = container_of(work, struct smp_chan,
1370 security_timer.work);
1371 struct l2cap_conn *conn = smp->conn;
1372
1373 BT_DBG("conn %p", conn);
1374
1375 hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM);
1376}
1377
1378static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
1379{
1380 struct l2cap_chan *chan = conn->smp;
1381 struct smp_chan *smp;
1382
1383 smp = kzalloc(sizeof(*smp), GFP_ATOMIC);
1384 if (!smp)
1385 return NULL;
1386
1387 smp->tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
1388 if (IS_ERR(smp->tfm_aes)) {
1389 BT_ERR("Unable to create AES crypto context");
1390 kzfree(smp);
1391 return NULL;
1392 }
1393
1394 smp->tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
1395 if (IS_ERR(smp->tfm_cmac)) {
1396 BT_ERR("Unable to create CMAC crypto context");
1397 crypto_free_cipher(smp->tfm_aes);
1398 kzfree(smp);
1399 return NULL;
1400 }
1401
1402 smp->conn = conn;
1403 chan->data = smp;
1404
1405 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL);
1406
1407 INIT_DELAYED_WORK(&smp->security_timer, smp_timeout);
1408
1409 hci_conn_hold(conn->hcon);
1410
1411 return smp;
1412}
1413
1414static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16])
1415{
1416 struct hci_conn *hcon = smp->conn->hcon;
1417 u8 *na, *nb, a[7], b[7];
1418
1419 if (hcon->out) {
1420 na = smp->prnd;
1421 nb = smp->rrnd;
1422 } else {
1423 na = smp->rrnd;
1424 nb = smp->prnd;
1425 }
1426
1427 memcpy(a, &hcon->init_addr, 6);
1428 memcpy(b, &hcon->resp_addr, 6);
1429 a[6] = hcon->init_addr_type;
1430 b[6] = hcon->resp_addr_type;
1431
1432 return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk);
1433}
1434
1435static void sc_dhkey_check(struct smp_chan *smp)
1436{
1437 struct hci_conn *hcon = smp->conn->hcon;
1438 struct smp_cmd_dhkey_check check;
1439 u8 a[7], b[7], *local_addr, *remote_addr;
1440 u8 io_cap[3], r[16];
1441
1442 memcpy(a, &hcon->init_addr, 6);
1443 memcpy(b, &hcon->resp_addr, 6);
1444 a[6] = hcon->init_addr_type;
1445 b[6] = hcon->resp_addr_type;
1446
1447 if (hcon->out) {
1448 local_addr = a;
1449 remote_addr = b;
1450 memcpy(io_cap, &smp->preq[1], 3);
1451 } else {
1452 local_addr = b;
1453 remote_addr = a;
1454 memcpy(io_cap, &smp->prsp[1], 3);
1455 }
1456
1457 memset(r, 0, sizeof(r));
1458
1459 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
1460 put_unaligned_le32(hcon->passkey_notify, r);
1461
1462 if (smp->method == REQ_OOB)
1463 memcpy(r, smp->rr, 16);
1464
1465 smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap,
1466 local_addr, remote_addr, check.e);
1467
1468 smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check);
1469}
1470
1471static u8 sc_passkey_send_confirm(struct smp_chan *smp)
1472{
1473 struct l2cap_conn *conn = smp->conn;
1474 struct hci_conn *hcon = conn->hcon;
1475 struct smp_cmd_pairing_confirm cfm;
1476 u8 r;
1477
1478 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1479 r |= 0x80;
1480
1481 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1482
1483 if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r,
1484 cfm.confirm_val))
1485 return SMP_UNSPECIFIED;
1486
1487 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
1488
1489 return 0;
1490}
1491
1492static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op)
1493{
1494 struct l2cap_conn *conn = smp->conn;
1495 struct hci_conn *hcon = conn->hcon;
1496 struct hci_dev *hdev = hcon->hdev;
1497 u8 cfm[16], r;
1498
1499 /* Ignore the PDU if we've already done 20 rounds (0 - 19) */
1500 if (smp->passkey_round >= 20)
1501 return 0;
1502
1503 switch (smp_op) {
1504 case SMP_CMD_PAIRING_RANDOM:
1505 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1506 r |= 0x80;
1507
1508 if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
1509 smp->rrnd, r, cfm))
1510 return SMP_UNSPECIFIED;
1511
1512 if (memcmp(smp->pcnf, cfm, 16))
1513 return SMP_CONFIRM_FAILED;
1514
1515 smp->passkey_round++;
1516
1517 if (smp->passkey_round == 20) {
1518 /* Generate MacKey and LTK */
1519 if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk))
1520 return SMP_UNSPECIFIED;
1521 }
1522
1523 /* The round is only complete when the initiator
1524 * receives pairing random.
1525 */
1526 if (!hcon->out) {
1527 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1528 sizeof(smp->prnd), smp->prnd);
1529 if (smp->passkey_round == 20)
1530 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1531 else
1532 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1533 return 0;
1534 }
1535
1536 /* Start the next round */
1537 if (smp->passkey_round != 20)
1538 return sc_passkey_round(smp, 0);
1539
1540 /* Passkey rounds are complete - start DHKey Check */
1541 sc_dhkey_check(smp);
1542 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1543
1544 break;
1545
1546 case SMP_CMD_PAIRING_CONFIRM:
1547 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
1548 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
1549 return 0;
1550 }
1551
1552 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1553
1554 if (hcon->out) {
1555 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1556 sizeof(smp->prnd), smp->prnd);
1557 return 0;
1558 }
1559
1560 return sc_passkey_send_confirm(smp);
1561
1562 case SMP_CMD_PUBLIC_KEY:
1563 default:
1564 /* Initiating device starts the round */
1565 if (!hcon->out)
1566 return 0;
1567
1568 BT_DBG("%s Starting passkey round %u", hdev->name,
1569 smp->passkey_round + 1);
1570
1571 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1572
1573 return sc_passkey_send_confirm(smp);
1574 }
1575
1576 return 0;
1577}
1578
1579static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey)
1580{
1581 struct l2cap_conn *conn = smp->conn;
1582 struct hci_conn *hcon = conn->hcon;
1583 u8 smp_op;
1584
1585 clear_bit(SMP_FLAG_WAIT_USER, &smp->flags);
1586
1587 switch (mgmt_op) {
1588 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1589 smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED);
1590 return 0;
1591 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1592 smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED);
1593 return 0;
1594 case MGMT_OP_USER_PASSKEY_REPLY:
1595 hcon->passkey_notify = le32_to_cpu(passkey);
1596 smp->passkey_round = 0;
1597
1598 if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags))
1599 smp_op = SMP_CMD_PAIRING_CONFIRM;
1600 else
1601 smp_op = 0;
1602
1603 if (sc_passkey_round(smp, smp_op))
1604 return -EIO;
1605
1606 return 0;
1607 }
1608
1609 /* Initiator sends DHKey check first */
1610 if (hcon->out) {
1611 sc_dhkey_check(smp);
1612 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1613 } else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) {
1614 sc_dhkey_check(smp);
1615 sc_add_ltk(smp);
1616 }
1617
1618 return 0;
1619}
1620
1621int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
1622{
1623 struct l2cap_conn *conn = hcon->l2cap_data;
1624 struct l2cap_chan *chan;
1625 struct smp_chan *smp;
1626 u32 value;
1627 int err;
1628
1629 BT_DBG("");
1630
1631 if (!conn)
1632 return -ENOTCONN;
1633
1634 chan = conn->smp;
1635 if (!chan)
1636 return -ENOTCONN;
1637
1638 l2cap_chan_lock(chan);
1639 if (!chan->data) {
1640 err = -ENOTCONN;
1641 goto unlock;
1642 }
1643
1644 smp = chan->data;
1645
1646 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1647 err = sc_user_reply(smp, mgmt_op, passkey);
1648 goto unlock;
1649 }
1650
1651 switch (mgmt_op) {
1652 case MGMT_OP_USER_PASSKEY_REPLY:
1653 value = le32_to_cpu(passkey);
1654 memset(smp->tk, 0, sizeof(smp->tk));
1655 BT_DBG("PassKey: %d", value);
1656 put_unaligned_le32(value, smp->tk);
1657 /* Fall Through */
1658 case MGMT_OP_USER_CONFIRM_REPLY:
1659 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
1660 break;
1661 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1662 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1663 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1664 err = 0;
1665 goto unlock;
1666 default:
1667 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1668 err = -EOPNOTSUPP;
1669 goto unlock;
1670 }
1671
1672 err = 0;
1673
1674 /* If it is our turn to send Pairing Confirm, do so now */
1675 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) {
1676 u8 rsp = smp_confirm(smp);
1677 if (rsp)
1678 smp_failure(conn, rsp);
1679 }
1680
1681unlock:
1682 l2cap_chan_unlock(chan);
1683 return err;
1684}
1685
1686static void build_bredr_pairing_cmd(struct smp_chan *smp,
1687 struct smp_cmd_pairing *req,
1688 struct smp_cmd_pairing *rsp)
1689{
1690 struct l2cap_conn *conn = smp->conn;
1691 struct hci_dev *hdev = conn->hcon->hdev;
1692 u8 local_dist = 0, remote_dist = 0;
1693
1694 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
1695 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1696 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1697 }
1698
1699 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
1700 remote_dist |= SMP_DIST_ID_KEY;
1701
1702 if (hci_dev_test_flag(hdev, HCI_PRIVACY))
1703 local_dist |= SMP_DIST_ID_KEY;
1704
1705 if (!rsp) {
1706 memset(req, 0, sizeof(*req));
1707
1708 req->auth_req = SMP_AUTH_CT2;
1709 req->init_key_dist = local_dist;
1710 req->resp_key_dist = remote_dist;
1711 req->max_key_size = conn->hcon->enc_key_size;
1712
1713 smp->remote_key_dist = remote_dist;
1714
1715 return;
1716 }
1717
1718 memset(rsp, 0, sizeof(*rsp));
1719
1720 rsp->auth_req = SMP_AUTH_CT2;
1721 rsp->max_key_size = conn->hcon->enc_key_size;
1722 rsp->init_key_dist = req->init_key_dist & remote_dist;
1723 rsp->resp_key_dist = req->resp_key_dist & local_dist;
1724
1725 smp->remote_key_dist = rsp->init_key_dist;
1726}
1727
1728static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
1729{
1730 struct smp_cmd_pairing rsp, *req = (void *) skb->data;
1731 struct l2cap_chan *chan = conn->smp;
1732 struct hci_dev *hdev = conn->hcon->hdev;
1733 struct smp_chan *smp;
1734 u8 key_size, auth, sec_level;
1735 int ret;
1736
1737 BT_DBG("conn %p", conn);
1738
1739 if (skb->len < sizeof(*req))
1740 return SMP_INVALID_PARAMS;
1741
1742 if (conn->hcon->role != HCI_ROLE_SLAVE)
1743 return SMP_CMD_NOTSUPP;
1744
1745 if (!chan->data)
1746 smp = smp_chan_create(conn);
1747 else
1748 smp = chan->data;
1749
1750 if (!smp)
1751 return SMP_UNSPECIFIED;
1752
1753 /* We didn't start the pairing, so match remote */
1754 auth = req->auth_req & AUTH_REQ_MASK(hdev);
1755
1756 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
1757 (auth & SMP_AUTH_BONDING))
1758 return SMP_PAIRING_NOTSUPP;
1759
1760 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1761 return SMP_AUTH_REQUIREMENTS;
1762
1763 smp->preq[0] = SMP_CMD_PAIRING_REQ;
1764 memcpy(&smp->preq[1], req, sizeof(*req));
1765 skb_pull(skb, sizeof(*req));
1766
1767 /* If the remote side's OOB flag is set it means it has
1768 * successfully received our local OOB data - therefore set the
1769 * flag to indicate that local OOB is in use.
1770 */
1771 if (req->oob_flag == SMP_OOB_PRESENT)
1772 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1773
1774 /* SMP over BR/EDR requires special treatment */
1775 if (conn->hcon->type == ACL_LINK) {
1776 /* We must have a BR/EDR SC link */
1777 if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) &&
1778 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
1779 return SMP_CROSS_TRANSP_NOT_ALLOWED;
1780
1781 set_bit(SMP_FLAG_SC, &smp->flags);
1782
1783 build_bredr_pairing_cmd(smp, req, &rsp);
1784
1785 if (req->auth_req & SMP_AUTH_CT2)
1786 set_bit(SMP_FLAG_CT2, &smp->flags);
1787
1788 key_size = min(req->max_key_size, rsp.max_key_size);
1789 if (check_enc_key_size(conn, key_size))
1790 return SMP_ENC_KEY_SIZE;
1791
1792 /* Clear bits which are generated but not distributed */
1793 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1794
1795 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1796 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1797 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1798
1799 smp_distribute_keys(smp);
1800 return 0;
1801 }
1802
1803 build_pairing_cmd(conn, req, &rsp, auth);
1804
1805 if (rsp.auth_req & SMP_AUTH_SC) {
1806 set_bit(SMP_FLAG_SC, &smp->flags);
1807
1808 if (rsp.auth_req & SMP_AUTH_CT2)
1809 set_bit(SMP_FLAG_CT2, &smp->flags);
1810 }
1811
1812 if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
1813 sec_level = BT_SECURITY_MEDIUM;
1814 else
1815 sec_level = authreq_to_seclevel(auth);
1816
1817 if (sec_level > conn->hcon->pending_sec_level)
1818 conn->hcon->pending_sec_level = sec_level;
1819
1820 /* If we need MITM check that it can be achieved */
1821 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1822 u8 method;
1823
1824 method = get_auth_method(smp, conn->hcon->io_capability,
1825 req->io_capability);
1826 if (method == JUST_WORKS || method == JUST_CFM)
1827 return SMP_AUTH_REQUIREMENTS;
1828 }
1829
1830 key_size = min(req->max_key_size, rsp.max_key_size);
1831 if (check_enc_key_size(conn, key_size))
1832 return SMP_ENC_KEY_SIZE;
1833
1834 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1835
1836 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1837 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1838
1839 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1840
1841 clear_bit(SMP_FLAG_INITIATOR, &smp->flags);
1842
1843 /* Strictly speaking we shouldn't allow Pairing Confirm for the
1844 * SC case, however some implementations incorrectly copy RFU auth
1845 * req bits from our security request, which may create a false
1846 * positive SC enablement.
1847 */
1848 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1849
1850 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1851 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
1852 /* Clear bits which are generated but not distributed */
1853 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1854 /* Wait for Public Key from Initiating Device */
1855 return 0;
1856 }
1857
1858 /* Request setup of TK */
1859 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability);
1860 if (ret)
1861 return SMP_UNSPECIFIED;
1862
1863 return 0;
1864}
1865
1866static u8 sc_send_public_key(struct smp_chan *smp)
1867{
1868 struct hci_dev *hdev = smp->conn->hcon->hdev;
1869
1870 BT_DBG("");
1871
1872 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) {
1873 struct l2cap_chan *chan = hdev->smp_data;
1874 struct smp_dev *smp_dev;
1875
1876 if (!chan || !chan->data)
1877 return SMP_UNSPECIFIED;
1878
1879 smp_dev = chan->data;
1880
1881 memcpy(smp->local_pk, smp_dev->local_pk, 64);
1882 memcpy(smp->local_sk, smp_dev->local_sk, 32);
1883 memcpy(smp->lr, smp_dev->local_rand, 16);
1884
1885 if (smp_dev->debug_key)
1886 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1887
1888 goto done;
1889 }
1890
1891 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
1892 BT_DBG("Using debug keys");
1893 memcpy(smp->local_pk, debug_pk, 64);
1894 memcpy(smp->local_sk, debug_sk, 32);
1895 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1896 } else {
1897 while (true) {
1898 /* Generate local key pair for Secure Connections */
1899 if (!ecc_make_key(smp->local_pk, smp->local_sk))
1900 return SMP_UNSPECIFIED;
1901
1902 /* This is unlikely, but we need to check that
1903 * we didn't accidentially generate a debug key.
1904 */
1905 if (memcmp(smp->local_sk, debug_sk, 32))
1906 break;
1907 }
1908 }
1909
1910done:
1911 SMP_DBG("Local Public Key X: %32phN", smp->local_pk);
1912 SMP_DBG("Local Public Key Y: %32phN", smp->local_pk + 32);
1913 SMP_DBG("Local Private Key: %32phN", smp->local_sk);
1914
1915 smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk);
1916
1917 return 0;
1918}
1919
1920static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
1921{
1922 struct smp_cmd_pairing *req, *rsp = (void *) skb->data;
1923 struct l2cap_chan *chan = conn->smp;
1924 struct smp_chan *smp = chan->data;
1925 struct hci_dev *hdev = conn->hcon->hdev;
1926 u8 key_size, auth;
1927 int ret;
1928
1929 BT_DBG("conn %p", conn);
1930
1931 if (skb->len < sizeof(*rsp))
1932 return SMP_INVALID_PARAMS;
1933
1934 if (conn->hcon->role != HCI_ROLE_MASTER)
1935 return SMP_CMD_NOTSUPP;
1936
1937 skb_pull(skb, sizeof(*rsp));
1938
1939 req = (void *) &smp->preq[1];
1940
1941 key_size = min(req->max_key_size, rsp->max_key_size);
1942 if (check_enc_key_size(conn, key_size))
1943 return SMP_ENC_KEY_SIZE;
1944
1945 auth = rsp->auth_req & AUTH_REQ_MASK(hdev);
1946
1947 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1948 return SMP_AUTH_REQUIREMENTS;
1949
1950 /* If the remote side's OOB flag is set it means it has
1951 * successfully received our local OOB data - therefore set the
1952 * flag to indicate that local OOB is in use.
1953 */
1954 if (rsp->oob_flag == SMP_OOB_PRESENT)
1955 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1956
1957 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1958 memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
1959
1960 /* Update remote key distribution in case the remote cleared
1961 * some bits that we had enabled in our request.
1962 */
1963 smp->remote_key_dist &= rsp->resp_key_dist;
1964
1965 if ((req->auth_req & SMP_AUTH_CT2) && (auth & SMP_AUTH_CT2))
1966 set_bit(SMP_FLAG_CT2, &smp->flags);
1967
1968 /* For BR/EDR this means we're done and can start phase 3 */
1969 if (conn->hcon->type == ACL_LINK) {
1970 /* Clear bits which are generated but not distributed */
1971 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1972 smp_distribute_keys(smp);
1973 return 0;
1974 }
1975
1976 if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC))
1977 set_bit(SMP_FLAG_SC, &smp->flags);
1978 else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH)
1979 conn->hcon->pending_sec_level = BT_SECURITY_HIGH;
1980
1981 /* If we need MITM check that it can be achieved */
1982 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1983 u8 method;
1984
1985 method = get_auth_method(smp, req->io_capability,
1986 rsp->io_capability);
1987 if (method == JUST_WORKS || method == JUST_CFM)
1988 return SMP_AUTH_REQUIREMENTS;
1989 }
1990
1991 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1992
1993 /* Update remote key distribution in case the remote cleared
1994 * some bits that we had enabled in our request.
1995 */
1996 smp->remote_key_dist &= rsp->resp_key_dist;
1997
1998 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1999 /* Clear bits which are generated but not distributed */
2000 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
2001 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
2002 return sc_send_public_key(smp);
2003 }
2004
2005 auth |= req->auth_req;
2006
2007 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability);
2008 if (ret)
2009 return SMP_UNSPECIFIED;
2010
2011 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
2012
2013 /* Can't compose response until we have been confirmed */
2014 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
2015 return smp_confirm(smp);
2016
2017 return 0;
2018}
2019
2020static u8 sc_check_confirm(struct smp_chan *smp)
2021{
2022 struct l2cap_conn *conn = smp->conn;
2023
2024 BT_DBG("");
2025
2026 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2027 return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM);
2028
2029 if (conn->hcon->out) {
2030 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2031 smp->prnd);
2032 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2033 }
2034
2035 return 0;
2036}
2037
2038/* Work-around for some implementations that incorrectly copy RFU bits
2039 * from our security request and thereby create the impression that
2040 * we're doing SC when in fact the remote doesn't support it.
2041 */
2042static int fixup_sc_false_positive(struct smp_chan *smp)
2043{
2044 struct l2cap_conn *conn = smp->conn;
2045 struct hci_conn *hcon = conn->hcon;
2046 struct hci_dev *hdev = hcon->hdev;
2047 struct smp_cmd_pairing *req, *rsp;
2048 u8 auth;
2049
2050 /* The issue is only observed when we're in slave role */
2051 if (hcon->out)
2052 return SMP_UNSPECIFIED;
2053
2054 if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) {
2055 BT_ERR("Refusing SMP SC -> legacy fallback in SC-only mode");
2056 return SMP_UNSPECIFIED;
2057 }
2058
2059 BT_ERR("Trying to fall back to legacy SMP");
2060
2061 req = (void *) &smp->preq[1];
2062 rsp = (void *) &smp->prsp[1];
2063
2064 /* Rebuild key dist flags which may have been cleared for SC */
2065 smp->remote_key_dist = (req->init_key_dist & rsp->resp_key_dist);
2066
2067 auth = req->auth_req & AUTH_REQ_MASK(hdev);
2068
2069 if (tk_request(conn, 0, auth, rsp->io_capability, req->io_capability)) {
2070 BT_ERR("Failed to fall back to legacy SMP");
2071 return SMP_UNSPECIFIED;
2072 }
2073
2074 clear_bit(SMP_FLAG_SC, &smp->flags);
2075
2076 return 0;
2077}
2078
2079static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
2080{
2081 struct l2cap_chan *chan = conn->smp;
2082 struct smp_chan *smp = chan->data;
2083
2084 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
2085
2086 if (skb->len < sizeof(smp->pcnf))
2087 return SMP_INVALID_PARAMS;
2088
2089 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
2090 skb_pull(skb, sizeof(smp->pcnf));
2091
2092 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
2093 int ret;
2094
2095 /* Public Key exchange must happen before any other steps */
2096 if (test_bit(SMP_FLAG_REMOTE_PK, &smp->flags))
2097 return sc_check_confirm(smp);
2098
2099 BT_ERR("Unexpected SMP Pairing Confirm");
2100
2101 ret = fixup_sc_false_positive(smp);
2102 if (ret)
2103 return ret;
2104 }
2105
2106 if (conn->hcon->out) {
2107 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2108 smp->prnd);
2109 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2110 return 0;
2111 }
2112
2113 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
2114 return smp_confirm(smp);
2115
2116 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
2117
2118 return 0;
2119}
2120
2121static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
2122{
2123 struct l2cap_chan *chan = conn->smp;
2124 struct smp_chan *smp = chan->data;
2125 struct hci_conn *hcon = conn->hcon;
2126 u8 *pkax, *pkbx, *na, *nb;
2127 u32 passkey;
2128 int err;
2129
2130 BT_DBG("conn %p", conn);
2131
2132 if (skb->len < sizeof(smp->rrnd))
2133 return SMP_INVALID_PARAMS;
2134
2135 memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd));
2136 skb_pull(skb, sizeof(smp->rrnd));
2137
2138 if (!test_bit(SMP_FLAG_SC, &smp->flags))
2139 return smp_random(smp);
2140
2141 if (hcon->out) {
2142 pkax = smp->local_pk;
2143 pkbx = smp->remote_pk;
2144 na = smp->prnd;
2145 nb = smp->rrnd;
2146 } else {
2147 pkax = smp->remote_pk;
2148 pkbx = smp->local_pk;
2149 na = smp->rrnd;
2150 nb = smp->prnd;
2151 }
2152
2153 if (smp->method == REQ_OOB) {
2154 if (!hcon->out)
2155 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2156 sizeof(smp->prnd), smp->prnd);
2157 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2158 goto mackey_and_ltk;
2159 }
2160
2161 /* Passkey entry has special treatment */
2162 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2163 return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM);
2164
2165 if (hcon->out) {
2166 u8 cfm[16];
2167
2168 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
2169 smp->rrnd, 0, cfm);
2170 if (err)
2171 return SMP_UNSPECIFIED;
2172
2173 if (memcmp(smp->pcnf, cfm, 16))
2174 return SMP_CONFIRM_FAILED;
2175 } else {
2176 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2177 smp->prnd);
2178 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2179 }
2180
2181mackey_and_ltk:
2182 /* Generate MacKey and LTK */
2183 err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk);
2184 if (err)
2185 return SMP_UNSPECIFIED;
2186
2187 if (smp->method == JUST_WORKS || smp->method == REQ_OOB) {
2188 if (hcon->out) {
2189 sc_dhkey_check(smp);
2190 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2191 }
2192 return 0;
2193 }
2194
2195 err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);
2196 if (err)
2197 return SMP_UNSPECIFIED;
2198
2199 err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type,
2200 hcon->dst_type, passkey, 0);
2201 if (err)
2202 return SMP_UNSPECIFIED;
2203
2204 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2205
2206 return 0;
2207}
2208
2209static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
2210{
2211 struct smp_ltk *key;
2212 struct hci_conn *hcon = conn->hcon;
2213
2214 key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role);
2215 if (!key)
2216 return false;
2217
2218 if (smp_ltk_sec_level(key) < sec_level)
2219 return false;
2220
2221 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
2222 return true;
2223
2224 hci_le_start_enc(hcon, key->ediv, key->rand, key->val, key->enc_size);
2225 hcon->enc_key_size = key->enc_size;
2226
2227 /* We never store STKs for master role, so clear this flag */
2228 clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
2229
2230 return true;
2231}
2232
2233bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level,
2234 enum smp_key_pref key_pref)
2235{
2236 if (sec_level == BT_SECURITY_LOW)
2237 return true;
2238
2239 /* If we're encrypted with an STK but the caller prefers using
2240 * LTK claim insufficient security. This way we allow the
2241 * connection to be re-encrypted with an LTK, even if the LTK
2242 * provides the same level of security. Only exception is if we
2243 * don't have an LTK (e.g. because of key distribution bits).
2244 */
2245 if (key_pref == SMP_USE_LTK &&
2246 test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) &&
2247 hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role))
2248 return false;
2249
2250 if (hcon->sec_level >= sec_level)
2251 return true;
2252
2253 return false;
2254}
2255
2256static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
2257{
2258 struct smp_cmd_security_req *rp = (void *) skb->data;
2259 struct smp_cmd_pairing cp;
2260 struct hci_conn *hcon = conn->hcon;
2261 struct hci_dev *hdev = hcon->hdev;
2262 struct smp_chan *smp;
2263 u8 sec_level, auth;
2264
2265 BT_DBG("conn %p", conn);
2266
2267 if (skb->len < sizeof(*rp))
2268 return SMP_INVALID_PARAMS;
2269
2270 if (hcon->role != HCI_ROLE_MASTER)
2271 return SMP_CMD_NOTSUPP;
2272
2273 auth = rp->auth_req & AUTH_REQ_MASK(hdev);
2274
2275 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
2276 return SMP_AUTH_REQUIREMENTS;
2277
2278 if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
2279 sec_level = BT_SECURITY_MEDIUM;
2280 else
2281 sec_level = authreq_to_seclevel(auth);
2282
2283 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
2284 return 0;
2285
2286 if (sec_level > hcon->pending_sec_level)
2287 hcon->pending_sec_level = sec_level;
2288
2289 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2290 return 0;
2291
2292 smp = smp_chan_create(conn);
2293 if (!smp)
2294 return SMP_UNSPECIFIED;
2295
2296 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
2297 (auth & SMP_AUTH_BONDING))
2298 return SMP_PAIRING_NOTSUPP;
2299
2300 skb_pull(skb, sizeof(*rp));
2301
2302 memset(&cp, 0, sizeof(cp));
2303 build_pairing_cmd(conn, &cp, NULL, auth);
2304
2305 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2306 memcpy(&smp->preq[1], &cp, sizeof(cp));
2307
2308 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2309 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2310
2311 return 0;
2312}
2313
2314int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
2315{
2316 struct l2cap_conn *conn = hcon->l2cap_data;
2317 struct l2cap_chan *chan;
2318 struct smp_chan *smp;
2319 __u8 authreq;
2320 int ret;
2321
2322 BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);
2323
2324 /* This may be NULL if there's an unexpected disconnection */
2325 if (!conn)
2326 return 1;
2327
2328 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED))
2329 return 1;
2330
2331 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
2332 return 1;
2333
2334 if (sec_level > hcon->pending_sec_level)
2335 hcon->pending_sec_level = sec_level;
2336
2337 if (hcon->role == HCI_ROLE_MASTER)
2338 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2339 return 0;
2340
2341 chan = conn->smp;
2342 if (!chan) {
2343 BT_ERR("SMP security requested but not available");
2344 return 1;
2345 }
2346
2347 l2cap_chan_lock(chan);
2348
2349 /* If SMP is already in progress ignore this request */
2350 if (chan->data) {
2351 ret = 0;
2352 goto unlock;
2353 }
2354
2355 smp = smp_chan_create(conn);
2356 if (!smp) {
2357 ret = 1;
2358 goto unlock;
2359 }
2360
2361 authreq = seclevel_to_authreq(sec_level);
2362
2363 if (hci_dev_test_flag(hcon->hdev, HCI_SC_ENABLED)) {
2364 authreq |= SMP_AUTH_SC;
2365 if (hci_dev_test_flag(hcon->hdev, HCI_SSP_ENABLED))
2366 authreq |= SMP_AUTH_CT2;
2367 }
2368
2369 /* Require MITM if IO Capability allows or the security level
2370 * requires it.
2371 */
2372 if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT ||
2373 hcon->pending_sec_level > BT_SECURITY_MEDIUM)
2374 authreq |= SMP_AUTH_MITM;
2375
2376 if (hcon->role == HCI_ROLE_MASTER) {
2377 struct smp_cmd_pairing cp;
2378
2379 build_pairing_cmd(conn, &cp, NULL, authreq);
2380 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2381 memcpy(&smp->preq[1], &cp, sizeof(cp));
2382
2383 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2384 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2385 } else {
2386 struct smp_cmd_security_req cp;
2387 cp.auth_req = authreq;
2388 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
2389 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ);
2390 }
2391
2392 set_bit(SMP_FLAG_INITIATOR, &smp->flags);
2393 ret = 0;
2394
2395unlock:
2396 l2cap_chan_unlock(chan);
2397 return ret;
2398}
2399
2400void smp_cancel_pairing(struct hci_conn *hcon)
2401{
2402 struct l2cap_conn *conn = hcon->l2cap_data;
2403 struct l2cap_chan *chan;
2404 struct smp_chan *smp;
2405
2406 if (!conn)
2407 return;
2408
2409 chan = conn->smp;
2410 if (!chan)
2411 return;
2412
2413 l2cap_chan_lock(chan);
2414
2415 smp = chan->data;
2416 if (smp) {
2417 if (test_bit(SMP_FLAG_COMPLETE, &smp->flags))
2418 smp_failure(conn, 0);
2419 else
2420 smp_failure(conn, SMP_UNSPECIFIED);
2421 }
2422
2423 l2cap_chan_unlock(chan);
2424}
2425
2426static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb)
2427{
2428 struct smp_cmd_encrypt_info *rp = (void *) skb->data;
2429 struct l2cap_chan *chan = conn->smp;
2430 struct smp_chan *smp = chan->data;
2431
2432 BT_DBG("conn %p", conn);
2433
2434 if (skb->len < sizeof(*rp))
2435 return SMP_INVALID_PARAMS;
2436
2437 SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT);
2438
2439 skb_pull(skb, sizeof(*rp));
2440
2441 memcpy(smp->tk, rp->ltk, sizeof(smp->tk));
2442
2443 return 0;
2444}
2445
2446static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
2447{
2448 struct smp_cmd_master_ident *rp = (void *) skb->data;
2449 struct l2cap_chan *chan = conn->smp;
2450 struct smp_chan *smp = chan->data;
2451 struct hci_dev *hdev = conn->hcon->hdev;
2452 struct hci_conn *hcon = conn->hcon;
2453 struct smp_ltk *ltk;
2454 u8 authenticated;
2455
2456 BT_DBG("conn %p", conn);
2457
2458 if (skb->len < sizeof(*rp))
2459 return SMP_INVALID_PARAMS;
2460
2461 /* Mark the information as received */
2462 smp->remote_key_dist &= ~SMP_DIST_ENC_KEY;
2463
2464 if (smp->remote_key_dist & SMP_DIST_ID_KEY)
2465 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
2466 else if (smp->remote_key_dist & SMP_DIST_SIGN)
2467 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2468
2469 skb_pull(skb, sizeof(*rp));
2470
2471 authenticated = (hcon->sec_level == BT_SECURITY_HIGH);
2472 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK,
2473 authenticated, smp->tk, smp->enc_key_size,
2474 rp->ediv, rp->rand);
2475 smp->ltk = ltk;
2476 if (!(smp->remote_key_dist & KEY_DIST_MASK))
2477 smp_distribute_keys(smp);
2478
2479 return 0;
2480}
2481
2482static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb)
2483{
2484 struct smp_cmd_ident_info *info = (void *) skb->data;
2485 struct l2cap_chan *chan = conn->smp;
2486 struct smp_chan *smp = chan->data;
2487
2488 BT_DBG("");
2489
2490 if (skb->len < sizeof(*info))
2491 return SMP_INVALID_PARAMS;
2492
2493 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO);
2494
2495 skb_pull(skb, sizeof(*info));
2496
2497 memcpy(smp->irk, info->irk, 16);
2498
2499 return 0;
2500}
2501
2502static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,
2503 struct sk_buff *skb)
2504{
2505 struct smp_cmd_ident_addr_info *info = (void *) skb->data;
2506 struct l2cap_chan *chan = conn->smp;
2507 struct smp_chan *smp = chan->data;
2508 struct hci_conn *hcon = conn->hcon;
2509 bdaddr_t rpa;
2510
2511 BT_DBG("");
2512
2513 if (skb->len < sizeof(*info))
2514 return SMP_INVALID_PARAMS;
2515
2516 /* Mark the information as received */
2517 smp->remote_key_dist &= ~SMP_DIST_ID_KEY;
2518
2519 if (smp->remote_key_dist & SMP_DIST_SIGN)
2520 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2521
2522 skb_pull(skb, sizeof(*info));
2523
2524 /* Strictly speaking the Core Specification (4.1) allows sending
2525 * an empty address which would force us to rely on just the IRK
2526 * as "identity information". However, since such
2527 * implementations are not known of and in order to not over
2528 * complicate our implementation, simply pretend that we never
2529 * received an IRK for such a device.
2530 *
2531 * The Identity Address must also be a Static Random or Public
2532 * Address, which hci_is_identity_address() checks for.
2533 */
2534 if (!bacmp(&info->bdaddr, BDADDR_ANY) ||
2535 !hci_is_identity_address(&info->bdaddr, info->addr_type)) {
2536 BT_ERR("Ignoring IRK with no identity address");
2537 goto distribute;
2538 }
2539
2540 bacpy(&smp->id_addr, &info->bdaddr);
2541 smp->id_addr_type = info->addr_type;
2542
2543 if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type))
2544 bacpy(&rpa, &hcon->dst);
2545 else
2546 bacpy(&rpa, BDADDR_ANY);
2547
2548 smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr,
2549 smp->id_addr_type, smp->irk, &rpa);
2550
2551distribute:
2552 if (!(smp->remote_key_dist & KEY_DIST_MASK))
2553 smp_distribute_keys(smp);
2554
2555 return 0;
2556}
2557
2558static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb)
2559{
2560 struct smp_cmd_sign_info *rp = (void *) skb->data;
2561 struct l2cap_chan *chan = conn->smp;
2562 struct smp_chan *smp = chan->data;
2563 struct smp_csrk *csrk;
2564
2565 BT_DBG("conn %p", conn);
2566
2567 if (skb->len < sizeof(*rp))
2568 return SMP_INVALID_PARAMS;
2569
2570 /* Mark the information as received */
2571 smp->remote_key_dist &= ~SMP_DIST_SIGN;
2572
2573 skb_pull(skb, sizeof(*rp));
2574
2575 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
2576 if (csrk) {
2577 if (conn->hcon->sec_level > BT_SECURITY_MEDIUM)
2578 csrk->type = MGMT_CSRK_REMOTE_AUTHENTICATED;
2579 else
2580 csrk->type = MGMT_CSRK_REMOTE_UNAUTHENTICATED;
2581 memcpy(csrk->val, rp->csrk, sizeof(csrk->val));
2582 }
2583 smp->csrk = csrk;
2584 smp_distribute_keys(smp);
2585
2586 return 0;
2587}
2588
2589static u8 sc_select_method(struct smp_chan *smp)
2590{
2591 struct l2cap_conn *conn = smp->conn;
2592 struct hci_conn *hcon = conn->hcon;
2593 struct smp_cmd_pairing *local, *remote;
2594 u8 local_mitm, remote_mitm, local_io, remote_io, method;
2595
2596 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags) ||
2597 test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags))
2598 return REQ_OOB;
2599
2600 /* The preq/prsp contain the raw Pairing Request/Response PDUs
2601 * which are needed as inputs to some crypto functions. To get
2602 * the "struct smp_cmd_pairing" from them we need to skip the
2603 * first byte which contains the opcode.
2604 */
2605 if (hcon->out) {
2606 local = (void *) &smp->preq[1];
2607 remote = (void *) &smp->prsp[1];
2608 } else {
2609 local = (void *) &smp->prsp[1];
2610 remote = (void *) &smp->preq[1];
2611 }
2612
2613 local_io = local->io_capability;
2614 remote_io = remote->io_capability;
2615
2616 local_mitm = (local->auth_req & SMP_AUTH_MITM);
2617 remote_mitm = (remote->auth_req & SMP_AUTH_MITM);
2618
2619 /* If either side wants MITM, look up the method from the table,
2620 * otherwise use JUST WORKS.
2621 */
2622 if (local_mitm || remote_mitm)
2623 method = get_auth_method(smp, local_io, remote_io);
2624 else
2625 method = JUST_WORKS;
2626
2627 /* Don't confirm locally initiated pairing attempts */
2628 if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags))
2629 method = JUST_WORKS;
2630
2631 return method;
2632}
2633
2634static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb)
2635{
2636 struct smp_cmd_public_key *key = (void *) skb->data;
2637 struct hci_conn *hcon = conn->hcon;
2638 struct l2cap_chan *chan = conn->smp;
2639 struct smp_chan *smp = chan->data;
2640 struct hci_dev *hdev = hcon->hdev;
2641 struct smp_cmd_pairing_confirm cfm;
2642 int err;
2643
2644 BT_DBG("conn %p", conn);
2645
2646 if (skb->len < sizeof(*key))
2647 return SMP_INVALID_PARAMS;
2648
2649 memcpy(smp->remote_pk, key, 64);
2650
2651 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags)) {
2652 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk,
2653 smp->rr, 0, cfm.confirm_val);
2654 if (err)
2655 return SMP_UNSPECIFIED;
2656
2657 if (memcmp(cfm.confirm_val, smp->pcnf, 16))
2658 return SMP_CONFIRM_FAILED;
2659 }
2660
2661 /* Non-initiating device sends its public key after receiving
2662 * the key from the initiating device.
2663 */
2664 if (!hcon->out) {
2665 err = sc_send_public_key(smp);
2666 if (err)
2667 return err;
2668 }
2669
2670 SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk);
2671 SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32);
2672
2673 if (!ecdh_shared_secret(smp->remote_pk, smp->local_sk, smp->dhkey))
2674 return SMP_UNSPECIFIED;
2675
2676 SMP_DBG("DHKey %32phN", smp->dhkey);
2677
2678 set_bit(SMP_FLAG_REMOTE_PK, &smp->flags);
2679
2680 smp->method = sc_select_method(smp);
2681
2682 BT_DBG("%s selected method 0x%02x", hdev->name, smp->method);
2683
2684 /* JUST_WORKS and JUST_CFM result in an unauthenticated key */
2685 if (smp->method == JUST_WORKS || smp->method == JUST_CFM)
2686 hcon->pending_sec_level = BT_SECURITY_MEDIUM;
2687 else
2688 hcon->pending_sec_level = BT_SECURITY_FIPS;
2689
2690 if (!memcmp(debug_pk, smp->remote_pk, 64))
2691 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
2692
2693 if (smp->method == DSP_PASSKEY) {
2694 get_random_bytes(&hcon->passkey_notify,
2695 sizeof(hcon->passkey_notify));
2696 hcon->passkey_notify %= 1000000;
2697 hcon->passkey_entered = 0;
2698 smp->passkey_round = 0;
2699 if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type,
2700 hcon->dst_type,
2701 hcon->passkey_notify,
2702 hcon->passkey_entered))
2703 return SMP_UNSPECIFIED;
2704 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2705 return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY);
2706 }
2707
2708 if (smp->method == REQ_OOB) {
2709 if (hcon->out)
2710 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2711 sizeof(smp->prnd), smp->prnd);
2712
2713 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2714
2715 return 0;
2716 }
2717
2718 if (hcon->out)
2719 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2720
2721 if (smp->method == REQ_PASSKEY) {
2722 if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type,
2723 hcon->dst_type))
2724 return SMP_UNSPECIFIED;
2725 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2726 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2727 return 0;
2728 }
2729
2730 /* The Initiating device waits for the non-initiating device to
2731 * send the confirm value.
2732 */
2733 if (conn->hcon->out)
2734 return 0;
2735
2736 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd,
2737 0, cfm.confirm_val);
2738 if (err)
2739 return SMP_UNSPECIFIED;
2740
2741 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
2742 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2743
2744 return 0;
2745}
2746
2747static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb)
2748{
2749 struct smp_cmd_dhkey_check *check = (void *) skb->data;
2750 struct l2cap_chan *chan = conn->smp;
2751 struct hci_conn *hcon = conn->hcon;
2752 struct smp_chan *smp = chan->data;
2753 u8 a[7], b[7], *local_addr, *remote_addr;
2754 u8 io_cap[3], r[16], e[16];
2755 int err;
2756
2757 BT_DBG("conn %p", conn);
2758
2759 if (skb->len < sizeof(*check))
2760 return SMP_INVALID_PARAMS;
2761
2762 memcpy(a, &hcon->init_addr, 6);
2763 memcpy(b, &hcon->resp_addr, 6);
2764 a[6] = hcon->init_addr_type;
2765 b[6] = hcon->resp_addr_type;
2766
2767 if (hcon->out) {
2768 local_addr = a;
2769 remote_addr = b;
2770 memcpy(io_cap, &smp->prsp[1], 3);
2771 } else {
2772 local_addr = b;
2773 remote_addr = a;
2774 memcpy(io_cap, &smp->preq[1], 3);
2775 }
2776
2777 memset(r, 0, sizeof(r));
2778
2779 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2780 put_unaligned_le32(hcon->passkey_notify, r);
2781 else if (smp->method == REQ_OOB)
2782 memcpy(r, smp->lr, 16);
2783
2784 err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r,
2785 io_cap, remote_addr, local_addr, e);
2786 if (err)
2787 return SMP_UNSPECIFIED;
2788
2789 if (memcmp(check->e, e, 16))
2790 return SMP_DHKEY_CHECK_FAILED;
2791
2792 if (!hcon->out) {
2793 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
2794 set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags);
2795 return 0;
2796 }
2797
2798 /* Slave sends DHKey check as response to master */
2799 sc_dhkey_check(smp);
2800 }
2801
2802 sc_add_ltk(smp);
2803
2804 if (hcon->out) {
2805 hci_le_start_enc(hcon, 0, 0, smp->tk, smp->enc_key_size);
2806 hcon->enc_key_size = smp->enc_key_size;
2807 }
2808
2809 return 0;
2810}
2811
2812static int smp_cmd_keypress_notify(struct l2cap_conn *conn,
2813 struct sk_buff *skb)
2814{
2815 struct smp_cmd_keypress_notify *kp = (void *) skb->data;
2816
2817 BT_DBG("value 0x%02x", kp->value);
2818
2819 return 0;
2820}
2821
2822static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb)
2823{
2824 struct l2cap_conn *conn = chan->conn;
2825 struct hci_conn *hcon = conn->hcon;
2826 struct smp_chan *smp;
2827 __u8 code, reason;
2828 int err = 0;
2829
2830 if (skb->len < 1)
2831 return -EILSEQ;
2832
2833 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) {
2834 reason = SMP_PAIRING_NOTSUPP;
2835 goto done;
2836 }
2837
2838 code = skb->data[0];
2839 skb_pull(skb, sizeof(code));
2840
2841 smp = chan->data;
2842
2843 if (code > SMP_CMD_MAX)
2844 goto drop;
2845
2846 if (smp && !test_and_clear_bit(code, &smp->allow_cmd))
2847 goto drop;
2848
2849 /* If we don't have a context the only allowed commands are
2850 * pairing request and security request.
2851 */
2852 if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ)
2853 goto drop;
2854
2855 switch (code) {
2856 case SMP_CMD_PAIRING_REQ:
2857 reason = smp_cmd_pairing_req(conn, skb);
2858 break;
2859
2860 case SMP_CMD_PAIRING_FAIL:
2861 smp_failure(conn, 0);
2862 err = -EPERM;
2863 break;
2864
2865 case SMP_CMD_PAIRING_RSP:
2866 reason = smp_cmd_pairing_rsp(conn, skb);
2867 break;
2868
2869 case SMP_CMD_SECURITY_REQ:
2870 reason = smp_cmd_security_req(conn, skb);
2871 break;
2872
2873 case SMP_CMD_PAIRING_CONFIRM:
2874 reason = smp_cmd_pairing_confirm(conn, skb);
2875 break;
2876
2877 case SMP_CMD_PAIRING_RANDOM:
2878 reason = smp_cmd_pairing_random(conn, skb);
2879 break;
2880
2881 case SMP_CMD_ENCRYPT_INFO:
2882 reason = smp_cmd_encrypt_info(conn, skb);
2883 break;
2884
2885 case SMP_CMD_MASTER_IDENT:
2886 reason = smp_cmd_master_ident(conn, skb);
2887 break;
2888
2889 case SMP_CMD_IDENT_INFO:
2890 reason = smp_cmd_ident_info(conn, skb);
2891 break;
2892
2893 case SMP_CMD_IDENT_ADDR_INFO:
2894 reason = smp_cmd_ident_addr_info(conn, skb);
2895 break;
2896
2897 case SMP_CMD_SIGN_INFO:
2898 reason = smp_cmd_sign_info(conn, skb);
2899 break;
2900
2901 case SMP_CMD_PUBLIC_KEY:
2902 reason = smp_cmd_public_key(conn, skb);
2903 break;
2904
2905 case SMP_CMD_DHKEY_CHECK:
2906 reason = smp_cmd_dhkey_check(conn, skb);
2907 break;
2908
2909 case SMP_CMD_KEYPRESS_NOTIFY:
2910 reason = smp_cmd_keypress_notify(conn, skb);
2911 break;
2912
2913 default:
2914 BT_DBG("Unknown command code 0x%2.2x", code);
2915 reason = SMP_CMD_NOTSUPP;
2916 goto done;
2917 }
2918
2919done:
2920 if (!err) {
2921 if (reason)
2922 smp_failure(conn, reason);
2923 kfree_skb(skb);
2924 }
2925
2926 return err;
2927
2928drop:
2929 BT_ERR("%s unexpected SMP command 0x%02x from %pMR", hcon->hdev->name,
2930 code, &hcon->dst);
2931 kfree_skb(skb);
2932 return 0;
2933}
2934
2935static void smp_teardown_cb(struct l2cap_chan *chan, int err)
2936{
2937 struct l2cap_conn *conn = chan->conn;
2938
2939 BT_DBG("chan %p", chan);
2940
2941 if (chan->data)
2942 smp_chan_destroy(conn);
2943
2944 conn->smp = NULL;
2945 l2cap_chan_put(chan);
2946}
2947
2948static void bredr_pairing(struct l2cap_chan *chan)
2949{
2950 struct l2cap_conn *conn = chan->conn;
2951 struct hci_conn *hcon = conn->hcon;
2952 struct hci_dev *hdev = hcon->hdev;
2953 struct smp_cmd_pairing req;
2954 struct smp_chan *smp;
2955
2956 BT_DBG("chan %p", chan);
2957
2958 /* Only new pairings are interesting */
2959 if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags))
2960 return;
2961
2962 /* Don't bother if we're not encrypted */
2963 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
2964 return;
2965
2966 /* Only master may initiate SMP over BR/EDR */
2967 if (hcon->role != HCI_ROLE_MASTER)
2968 return;
2969
2970 /* Secure Connections support must be enabled */
2971 if (!hci_dev_test_flag(hdev, HCI_SC_ENABLED))
2972 return;
2973
2974 /* BR/EDR must use Secure Connections for SMP */
2975 if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) &&
2976 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
2977 return;
2978
2979 /* If our LE support is not enabled don't do anything */
2980 if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED))
2981 return;
2982
2983 /* Don't bother if remote LE support is not enabled */
2984 if (!lmp_host_le_capable(hcon))
2985 return;
2986
2987 /* Remote must support SMP fixed chan for BR/EDR */
2988 if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR))
2989 return;
2990
2991 /* Don't bother if SMP is already ongoing */
2992 if (chan->data)
2993 return;
2994
2995 smp = smp_chan_create(conn);
2996 if (!smp) {
2997 BT_ERR("%s unable to create SMP context for BR/EDR",
2998 hdev->name);
2999 return;
3000 }
3001
3002 set_bit(SMP_FLAG_SC, &smp->flags);
3003
3004 BT_DBG("%s starting SMP over BR/EDR", hdev->name);
3005
3006 /* Prepare and send the BR/EDR SMP Pairing Request */
3007 build_bredr_pairing_cmd(smp, &req, NULL);
3008
3009 smp->preq[0] = SMP_CMD_PAIRING_REQ;
3010 memcpy(&smp->preq[1], &req, sizeof(req));
3011
3012 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req);
3013 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
3014}
3015
3016static void smp_resume_cb(struct l2cap_chan *chan)
3017{
3018 struct smp_chan *smp = chan->data;
3019 struct l2cap_conn *conn = chan->conn;
3020 struct hci_conn *hcon = conn->hcon;
3021
3022 BT_DBG("chan %p", chan);
3023
3024 if (hcon->type == ACL_LINK) {
3025 bredr_pairing(chan);
3026 return;
3027 }
3028
3029 if (!smp)
3030 return;
3031
3032 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
3033 return;
3034
3035 cancel_delayed_work(&smp->security_timer);
3036
3037 smp_distribute_keys(smp);
3038}
3039
3040static void smp_ready_cb(struct l2cap_chan *chan)
3041{
3042 struct l2cap_conn *conn = chan->conn;
3043 struct hci_conn *hcon = conn->hcon;
3044
3045 BT_DBG("chan %p", chan);
3046
3047 /* No need to call l2cap_chan_hold() here since we already own
3048 * the reference taken in smp_new_conn_cb(). This is just the
3049 * first time that we tie it to a specific pointer. The code in
3050 * l2cap_core.c ensures that there's no risk this function wont
3051 * get called if smp_new_conn_cb was previously called.
3052 */
3053 conn->smp = chan;
3054
3055 if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
3056 bredr_pairing(chan);
3057}
3058
3059static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
3060{
3061 int err;
3062
3063 BT_DBG("chan %p", chan);
3064
3065 err = smp_sig_channel(chan, skb);
3066 if (err) {
3067 struct smp_chan *smp = chan->data;
3068
3069 if (smp)
3070 cancel_delayed_work_sync(&smp->security_timer);
3071
3072 hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE);
3073 }
3074
3075 return err;
3076}
3077
3078static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan,
3079 unsigned long hdr_len,
3080 unsigned long len, int nb)
3081{
3082 struct sk_buff *skb;
3083
3084 skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL);
3085 if (!skb)
3086 return ERR_PTR(-ENOMEM);
3087
3088 skb->priority = HCI_PRIO_MAX;
3089 bt_cb(skb)->l2cap.chan = chan;
3090
3091 return skb;
3092}
3093
3094static const struct l2cap_ops smp_chan_ops = {
3095 .name = "Security Manager",
3096 .ready = smp_ready_cb,
3097 .recv = smp_recv_cb,
3098 .alloc_skb = smp_alloc_skb_cb,
3099 .teardown = smp_teardown_cb,
3100 .resume = smp_resume_cb,
3101
3102 .new_connection = l2cap_chan_no_new_connection,
3103 .state_change = l2cap_chan_no_state_change,
3104 .close = l2cap_chan_no_close,
3105 .defer = l2cap_chan_no_defer,
3106 .suspend = l2cap_chan_no_suspend,
3107 .set_shutdown = l2cap_chan_no_set_shutdown,
3108 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
3109};
3110
3111static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan)
3112{
3113 struct l2cap_chan *chan;
3114
3115 BT_DBG("pchan %p", pchan);
3116
3117 chan = l2cap_chan_create();
3118 if (!chan)
3119 return NULL;
3120
3121 chan->chan_type = pchan->chan_type;
3122 chan->ops = &smp_chan_ops;
3123 chan->scid = pchan->scid;
3124 chan->dcid = chan->scid;
3125 chan->imtu = pchan->imtu;
3126 chan->omtu = pchan->omtu;
3127 chan->mode = pchan->mode;
3128
3129 /* Other L2CAP channels may request SMP routines in order to
3130 * change the security level. This means that the SMP channel
3131 * lock must be considered in its own category to avoid lockdep
3132 * warnings.
3133 */
3134 atomic_set(&chan->nesting, L2CAP_NESTING_SMP);
3135
3136 BT_DBG("created chan %p", chan);
3137
3138 return chan;
3139}
3140
3141static const struct l2cap_ops smp_root_chan_ops = {
3142 .name = "Security Manager Root",
3143 .new_connection = smp_new_conn_cb,
3144
3145 /* None of these are implemented for the root channel */
3146 .close = l2cap_chan_no_close,
3147 .alloc_skb = l2cap_chan_no_alloc_skb,
3148 .recv = l2cap_chan_no_recv,
3149 .state_change = l2cap_chan_no_state_change,
3150 .teardown = l2cap_chan_no_teardown,
3151 .ready = l2cap_chan_no_ready,
3152 .defer = l2cap_chan_no_defer,
3153 .suspend = l2cap_chan_no_suspend,
3154 .resume = l2cap_chan_no_resume,
3155 .set_shutdown = l2cap_chan_no_set_shutdown,
3156 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
3157};
3158
3159static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid)
3160{
3161 struct l2cap_chan *chan;
3162 struct smp_dev *smp;
3163 struct crypto_cipher *tfm_aes;
3164 struct crypto_shash *tfm_cmac;
3165
3166 if (cid == L2CAP_CID_SMP_BREDR) {
3167 smp = NULL;
3168 goto create_chan;
3169 }
3170
3171 smp = kzalloc(sizeof(*smp), GFP_KERNEL);
3172 if (!smp)
3173 return ERR_PTR(-ENOMEM);
3174
3175 tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
3176 if (IS_ERR(tfm_aes)) {
3177 BT_ERR("Unable to create AES crypto context");
3178 kzfree(smp);
3179 return ERR_CAST(tfm_aes);
3180 }
3181
3182 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
3183 if (IS_ERR(tfm_cmac)) {
3184 BT_ERR("Unable to create CMAC crypto context");
3185 crypto_free_cipher(tfm_aes);
3186 kzfree(smp);
3187 return ERR_CAST(tfm_cmac);
3188 }
3189
3190 smp->tfm_aes = tfm_aes;
3191 smp->tfm_cmac = tfm_cmac;
3192 smp->min_key_size = SMP_MIN_ENC_KEY_SIZE;
3193 smp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
3194
3195create_chan:
3196 chan = l2cap_chan_create();
3197 if (!chan) {
3198 if (smp) {
3199 crypto_free_cipher(smp->tfm_aes);
3200 crypto_free_shash(smp->tfm_cmac);
3201 kzfree(smp);
3202 }
3203 return ERR_PTR(-ENOMEM);
3204 }
3205
3206 chan->data = smp;
3207
3208 l2cap_add_scid(chan, cid);
3209
3210 l2cap_chan_set_defaults(chan);
3211
3212 if (cid == L2CAP_CID_SMP) {
3213 u8 bdaddr_type;
3214
3215 hci_copy_identity_address(hdev, &chan->src, &bdaddr_type);
3216
3217 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
3218 chan->src_type = BDADDR_LE_PUBLIC;
3219 else
3220 chan->src_type = BDADDR_LE_RANDOM;
3221 } else {
3222 bacpy(&chan->src, &hdev->bdaddr);
3223 chan->src_type = BDADDR_BREDR;
3224 }
3225
3226 chan->state = BT_LISTEN;
3227 chan->mode = L2CAP_MODE_BASIC;
3228 chan->imtu = L2CAP_DEFAULT_MTU;
3229 chan->ops = &smp_root_chan_ops;
3230
3231 /* Set correct nesting level for a parent/listening channel */
3232 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
3233
3234 return chan;
3235}
3236
3237static void smp_del_chan(struct l2cap_chan *chan)
3238{
3239 struct smp_dev *smp;
3240
3241 BT_DBG("chan %p", chan);
3242
3243 smp = chan->data;
3244 if (smp) {
3245 chan->data = NULL;
3246 crypto_free_cipher(smp->tfm_aes);
3247 crypto_free_shash(smp->tfm_cmac);
3248 kzfree(smp);
3249 }
3250
3251 l2cap_chan_put(chan);
3252}
3253
3254static ssize_t force_bredr_smp_read(struct file *file,
3255 char __user *user_buf,
3256 size_t count, loff_t *ppos)
3257{
3258 struct hci_dev *hdev = file->private_data;
3259 char buf[3];
3260
3261 buf[0] = hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP) ? 'Y': 'N';
3262 buf[1] = '\n';
3263 buf[2] = '\0';
3264 return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
3265}
3266
3267static ssize_t force_bredr_smp_write(struct file *file,
3268 const char __user *user_buf,
3269 size_t count, loff_t *ppos)
3270{
3271 struct hci_dev *hdev = file->private_data;
3272 char buf[32];
3273 size_t buf_size = min(count, (sizeof(buf)-1));
3274 bool enable;
3275
3276 if (copy_from_user(buf, user_buf, buf_size))
3277 return -EFAULT;
3278
3279 buf[buf_size] = '\0';
3280 if (strtobool(buf, &enable))
3281 return -EINVAL;
3282
3283 if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3284 return -EALREADY;
3285
3286 if (enable) {
3287 struct l2cap_chan *chan;
3288
3289 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3290 if (IS_ERR(chan))
3291 return PTR_ERR(chan);
3292
3293 hdev->smp_bredr_data = chan;
3294 } else {
3295 struct l2cap_chan *chan;
3296
3297 chan = hdev->smp_bredr_data;
3298 hdev->smp_bredr_data = NULL;
3299 smp_del_chan(chan);
3300 }
3301
3302 hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP);
3303
3304 return count;
3305}
3306
3307static const struct file_operations force_bredr_smp_fops = {
3308 .open = simple_open,
3309 .read = force_bredr_smp_read,
3310 .write = force_bredr_smp_write,
3311 .llseek = default_llseek,
3312};
3313
3314static ssize_t le_min_key_size_read(struct file *file,
3315 char __user *user_buf,
3316 size_t count, loff_t *ppos)
3317{
3318 struct hci_dev *hdev = file->private_data;
3319 char buf[4];
3320
3321 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->min_key_size);
3322
3323 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf));
3324}
3325
3326static ssize_t le_min_key_size_write(struct file *file,
3327 const char __user *user_buf,
3328 size_t count, loff_t *ppos)
3329{
3330 struct hci_dev *hdev = file->private_data;
3331 char buf[32];
3332 size_t buf_size = min(count, (sizeof(buf) - 1));
3333 u8 key_size;
3334
3335 if (copy_from_user(buf, user_buf, buf_size))
3336 return -EFAULT;
3337
3338 buf[buf_size] = '\0';
3339
3340 sscanf(buf, "%hhu", &key_size);
3341
3342 if (key_size > SMP_DEV(hdev)->max_key_size ||
3343 key_size < SMP_MIN_ENC_KEY_SIZE)
3344 return -EINVAL;
3345
3346 SMP_DEV(hdev)->min_key_size = key_size;
3347
3348 return count;
3349}
3350
3351static const struct file_operations le_min_key_size_fops = {
3352 .open = simple_open,
3353 .read = le_min_key_size_read,
3354 .write = le_min_key_size_write,
3355 .llseek = default_llseek,
3356};
3357
3358static ssize_t le_max_key_size_read(struct file *file,
3359 char __user *user_buf,
3360 size_t count, loff_t *ppos)
3361{
3362 struct hci_dev *hdev = file->private_data;
3363 char buf[4];
3364
3365 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->max_key_size);
3366
3367 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf));
3368}
3369
3370static ssize_t le_max_key_size_write(struct file *file,
3371 const char __user *user_buf,
3372 size_t count, loff_t *ppos)
3373{
3374 struct hci_dev *hdev = file->private_data;
3375 char buf[32];
3376 size_t buf_size = min(count, (sizeof(buf) - 1));
3377 u8 key_size;
3378
3379 if (copy_from_user(buf, user_buf, buf_size))
3380 return -EFAULT;
3381
3382 buf[buf_size] = '\0';
3383
3384 sscanf(buf, "%hhu", &key_size);
3385
3386 if (key_size > SMP_MAX_ENC_KEY_SIZE ||
3387 key_size < SMP_DEV(hdev)->min_key_size)
3388 return -EINVAL;
3389
3390 SMP_DEV(hdev)->max_key_size = key_size;
3391
3392 return count;
3393}
3394
3395static const struct file_operations le_max_key_size_fops = {
3396 .open = simple_open,
3397 .read = le_max_key_size_read,
3398 .write = le_max_key_size_write,
3399 .llseek = default_llseek,
3400};
3401
3402int smp_register(struct hci_dev *hdev)
3403{
3404 struct l2cap_chan *chan;
3405
3406 BT_DBG("%s", hdev->name);
3407
3408 /* If the controller does not support Low Energy operation, then
3409 * there is also no need to register any SMP channel.
3410 */
3411 if (!lmp_le_capable(hdev))
3412 return 0;
3413
3414 if (WARN_ON(hdev->smp_data)) {
3415 chan = hdev->smp_data;
3416 hdev->smp_data = NULL;
3417 smp_del_chan(chan);
3418 }
3419
3420 chan = smp_add_cid(hdev, L2CAP_CID_SMP);
3421 if (IS_ERR(chan))
3422 return PTR_ERR(chan);
3423
3424 hdev->smp_data = chan;
3425
3426 debugfs_create_file("le_min_key_size", 0644, hdev->debugfs, hdev,
3427 &le_min_key_size_fops);
3428 debugfs_create_file("le_max_key_size", 0644, hdev->debugfs, hdev,
3429 &le_max_key_size_fops);
3430
3431 /* If the controller does not support BR/EDR Secure Connections
3432 * feature, then the BR/EDR SMP channel shall not be present.
3433 *
3434 * To test this with Bluetooth 4.0 controllers, create a debugfs
3435 * switch that allows forcing BR/EDR SMP support and accepting
3436 * cross-transport pairing on non-AES encrypted connections.
3437 */
3438 if (!lmp_sc_capable(hdev)) {
3439 debugfs_create_file("force_bredr_smp", 0644, hdev->debugfs,
3440 hdev, &force_bredr_smp_fops);
3441
3442 /* Flag can be already set here (due to power toggle) */
3443 if (!hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3444 return 0;
3445 }
3446
3447 if (WARN_ON(hdev->smp_bredr_data)) {
3448 chan = hdev->smp_bredr_data;
3449 hdev->smp_bredr_data = NULL;
3450 smp_del_chan(chan);
3451 }
3452
3453 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3454 if (IS_ERR(chan)) {
3455 int err = PTR_ERR(chan);
3456 chan = hdev->smp_data;
3457 hdev->smp_data = NULL;
3458 smp_del_chan(chan);
3459 return err;
3460 }
3461
3462 hdev->smp_bredr_data = chan;
3463
3464 return 0;
3465}
3466
3467void smp_unregister(struct hci_dev *hdev)
3468{
3469 struct l2cap_chan *chan;
3470
3471 if (hdev->smp_bredr_data) {
3472 chan = hdev->smp_bredr_data;
3473 hdev->smp_bredr_data = NULL;
3474 smp_del_chan(chan);
3475 }
3476
3477 if (hdev->smp_data) {
3478 chan = hdev->smp_data;
3479 hdev->smp_data = NULL;
3480 smp_del_chan(chan);
3481 }
3482}
3483
3484#if IS_ENABLED(CONFIG_BT_SELFTEST_SMP)
3485
3486static int __init test_ah(struct crypto_cipher *tfm_aes)
3487{
3488 const u8 irk[16] = {
3489 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3490 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3491 const u8 r[3] = { 0x94, 0x81, 0x70 };
3492 const u8 exp[3] = { 0xaa, 0xfb, 0x0d };
3493 u8 res[3];
3494 int err;
3495
3496 err = smp_ah(tfm_aes, irk, r, res);
3497 if (err)
3498 return err;
3499
3500 if (memcmp(res, exp, 3))
3501 return -EINVAL;
3502
3503 return 0;
3504}
3505
3506static int __init test_c1(struct crypto_cipher *tfm_aes)
3507{
3508 const u8 k[16] = {
3509 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
3510 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
3511 const u8 r[16] = {
3512 0xe0, 0x2e, 0x70, 0xc6, 0x4e, 0x27, 0x88, 0x63,
3513 0x0e, 0x6f, 0xad, 0x56, 0x21, 0xd5, 0x83, 0x57 };
3514 const u8 preq[7] = { 0x01, 0x01, 0x00, 0x00, 0x10, 0x07, 0x07 };
3515 const u8 pres[7] = { 0x02, 0x03, 0x00, 0x00, 0x08, 0x00, 0x05 };
3516 const u8 _iat = 0x01;
3517 const u8 _rat = 0x00;
3518 const bdaddr_t ra = { { 0xb6, 0xb5, 0xb4, 0xb3, 0xb2, 0xb1 } };
3519 const bdaddr_t ia = { { 0xa6, 0xa5, 0xa4, 0xa3, 0xa2, 0xa1 } };
3520 const u8 exp[16] = {
3521 0x86, 0x3b, 0xf1, 0xbe, 0xc5, 0x4d, 0xa7, 0xd2,
3522 0xea, 0x88, 0x89, 0x87, 0xef, 0x3f, 0x1e, 0x1e };
3523 u8 res[16];
3524 int err;
3525
3526 err = smp_c1(tfm_aes, k, r, preq, pres, _iat, &ia, _rat, &ra, res);
3527 if (err)
3528 return err;
3529
3530 if (memcmp(res, exp, 16))
3531 return -EINVAL;
3532
3533 return 0;
3534}
3535
3536static int __init test_s1(struct crypto_cipher *tfm_aes)
3537{
3538 const u8 k[16] = {
3539 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
3540 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
3541 const u8 r1[16] = {
3542 0x88, 0x77, 0x66, 0x55, 0x44, 0x33, 0x22, 0x11 };
3543 const u8 r2[16] = {
3544 0x00, 0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa, 0x99 };
3545 const u8 exp[16] = {
3546 0x62, 0xa0, 0x6d, 0x79, 0xae, 0x16, 0x42, 0x5b,
3547 0x9b, 0xf4, 0xb0, 0xe8, 0xf0, 0xe1, 0x1f, 0x9a };
3548 u8 res[16];
3549 int err;
3550
3551 err = smp_s1(tfm_aes, k, r1, r2, res);
3552 if (err)
3553 return err;
3554
3555 if (memcmp(res, exp, 16))
3556 return -EINVAL;
3557
3558 return 0;
3559}
3560
3561static int __init test_f4(struct crypto_shash *tfm_cmac)
3562{
3563 const u8 u[32] = {
3564 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
3565 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
3566 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
3567 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 };
3568 const u8 v[32] = {
3569 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b,
3570 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59,
3571 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90,
3572 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 };
3573 const u8 x[16] = {
3574 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3575 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3576 const u8 z = 0x00;
3577 const u8 exp[16] = {
3578 0x2d, 0x87, 0x74, 0xa9, 0xbe, 0xa1, 0xed, 0xf1,
3579 0x1c, 0xbd, 0xa9, 0x07, 0xf1, 0x16, 0xc9, 0xf2 };
3580 u8 res[16];
3581 int err;
3582
3583 err = smp_f4(tfm_cmac, u, v, x, z, res);
3584 if (err)
3585 return err;
3586
3587 if (memcmp(res, exp, 16))
3588 return -EINVAL;
3589
3590 return 0;
3591}
3592
3593static int __init test_f5(struct crypto_shash *tfm_cmac)
3594{
3595 const u8 w[32] = {
3596 0x98, 0xa6, 0xbf, 0x73, 0xf3, 0x34, 0x8d, 0x86,
3597 0xf1, 0x66, 0xf8, 0xb4, 0x13, 0x6b, 0x79, 0x99,
3598 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3599 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3600 const u8 n1[16] = {
3601 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3602 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3603 const u8 n2[16] = {
3604 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3605 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3606 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 };
3607 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 };
3608 const u8 exp_ltk[16] = {
3609 0x38, 0x0a, 0x75, 0x94, 0xb5, 0x22, 0x05, 0x98,
3610 0x23, 0xcd, 0xd7, 0x69, 0x11, 0x79, 0x86, 0x69 };
3611 const u8 exp_mackey[16] = {
3612 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd,
3613 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 };
3614 u8 mackey[16], ltk[16];
3615 int err;
3616
3617 err = smp_f5(tfm_cmac, w, n1, n2, a1, a2, mackey, ltk);
3618 if (err)
3619 return err;
3620
3621 if (memcmp(mackey, exp_mackey, 16))
3622 return -EINVAL;
3623
3624 if (memcmp(ltk, exp_ltk, 16))
3625 return -EINVAL;
3626
3627 return 0;
3628}
3629
3630static int __init test_f6(struct crypto_shash *tfm_cmac)
3631{
3632 const u8 w[16] = {
3633 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd,
3634 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 };
3635 const u8 n1[16] = {
3636 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3637 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3638 const u8 n2[16] = {
3639 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3640 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3641 const u8 r[16] = {
3642 0xc8, 0x0f, 0x2d, 0x0c, 0xd2, 0x42, 0xda, 0x08,
3643 0x54, 0xbb, 0x53, 0xb4, 0x3b, 0x34, 0xa3, 0x12 };
3644 const u8 io_cap[3] = { 0x02, 0x01, 0x01 };
3645 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 };
3646 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 };
3647 const u8 exp[16] = {
3648 0x61, 0x8f, 0x95, 0xda, 0x09, 0x0b, 0x6c, 0xd2,
3649 0xc5, 0xe8, 0xd0, 0x9c, 0x98, 0x73, 0xc4, 0xe3 };
3650 u8 res[16];
3651 int err;
3652
3653 err = smp_f6(tfm_cmac, w, n1, n2, r, io_cap, a1, a2, res);
3654 if (err)
3655 return err;
3656
3657 if (memcmp(res, exp, 16))
3658 return -EINVAL;
3659
3660 return 0;
3661}
3662
3663static int __init test_g2(struct crypto_shash *tfm_cmac)
3664{
3665 const u8 u[32] = {
3666 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
3667 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
3668 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
3669 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 };
3670 const u8 v[32] = {
3671 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b,
3672 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59,
3673 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90,
3674 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 };
3675 const u8 x[16] = {
3676 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3677 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3678 const u8 y[16] = {
3679 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3680 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3681 const u32 exp_val = 0x2f9ed5ba % 1000000;
3682 u32 val;
3683 int err;
3684
3685 err = smp_g2(tfm_cmac, u, v, x, y, &val);
3686 if (err)
3687 return err;
3688
3689 if (val != exp_val)
3690 return -EINVAL;
3691
3692 return 0;
3693}
3694
3695static int __init test_h6(struct crypto_shash *tfm_cmac)
3696{
3697 const u8 w[16] = {
3698 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3699 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3700 const u8 key_id[4] = { 0x72, 0x62, 0x65, 0x6c };
3701 const u8 exp[16] = {
3702 0x99, 0x63, 0xb1, 0x80, 0xe2, 0xa9, 0xd3, 0xe8,
3703 0x1c, 0xc9, 0x6d, 0xe7, 0x02, 0xe1, 0x9a, 0x2d };
3704 u8 res[16];
3705 int err;
3706
3707 err = smp_h6(tfm_cmac, w, key_id, res);
3708 if (err)
3709 return err;
3710
3711 if (memcmp(res, exp, 16))
3712 return -EINVAL;
3713
3714 return 0;
3715}
3716
3717static char test_smp_buffer[32];
3718
3719static ssize_t test_smp_read(struct file *file, char __user *user_buf,
3720 size_t count, loff_t *ppos)
3721{
3722 return simple_read_from_buffer(user_buf, count, ppos, test_smp_buffer,
3723 strlen(test_smp_buffer));
3724}
3725
3726static const struct file_operations test_smp_fops = {
3727 .open = simple_open,
3728 .read = test_smp_read,
3729 .llseek = default_llseek,
3730};
3731
3732static int __init run_selftests(struct crypto_cipher *tfm_aes,
3733 struct crypto_shash *tfm_cmac)
3734{
3735 ktime_t calltime, delta, rettime;
3736 unsigned long long duration;
3737 int err;
3738
3739 calltime = ktime_get();
3740
3741 err = test_ah(tfm_aes);
3742 if (err) {
3743 BT_ERR("smp_ah test failed");
3744 goto done;
3745 }
3746
3747 err = test_c1(tfm_aes);
3748 if (err) {
3749 BT_ERR("smp_c1 test failed");
3750 goto done;
3751 }
3752
3753 err = test_s1(tfm_aes);
3754 if (err) {
3755 BT_ERR("smp_s1 test failed");
3756 goto done;
3757 }
3758
3759 err = test_f4(tfm_cmac);
3760 if (err) {
3761 BT_ERR("smp_f4 test failed");
3762 goto done;
3763 }
3764
3765 err = test_f5(tfm_cmac);
3766 if (err) {
3767 BT_ERR("smp_f5 test failed");
3768 goto done;
3769 }
3770
3771 err = test_f6(tfm_cmac);
3772 if (err) {
3773 BT_ERR("smp_f6 test failed");
3774 goto done;
3775 }
3776
3777 err = test_g2(tfm_cmac);
3778 if (err) {
3779 BT_ERR("smp_g2 test failed");
3780 goto done;
3781 }
3782
3783 err = test_h6(tfm_cmac);
3784 if (err) {
3785 BT_ERR("smp_h6 test failed");
3786 goto done;
3787 }
3788
3789 rettime = ktime_get();
3790 delta = ktime_sub(rettime, calltime);
3791 duration = (unsigned long long) ktime_to_ns(delta) >> 10;
3792
3793 BT_INFO("SMP test passed in %llu usecs", duration);
3794
3795done:
3796 if (!err)
3797 snprintf(test_smp_buffer, sizeof(test_smp_buffer),
3798 "PASS (%llu usecs)\n", duration);
3799 else
3800 snprintf(test_smp_buffer, sizeof(test_smp_buffer), "FAIL\n");
3801
3802 debugfs_create_file("selftest_smp", 0444, bt_debugfs, NULL,
3803 &test_smp_fops);
3804
3805 return err;
3806}
3807
3808int __init bt_selftest_smp(void)
3809{
3810 struct crypto_cipher *tfm_aes;
3811 struct crypto_shash *tfm_cmac;
3812 int err;
3813
3814 tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
3815 if (IS_ERR(tfm_aes)) {
3816 BT_ERR("Unable to create AES crypto context");
3817 return PTR_ERR(tfm_aes);
3818 }
3819
3820 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, CRYPTO_ALG_ASYNC);
3821 if (IS_ERR(tfm_cmac)) {
3822 BT_ERR("Unable to create CMAC crypto context");
3823 crypto_free_cipher(tfm_aes);
3824 return PTR_ERR(tfm_cmac);
3825 }
3826
3827 err = run_selftests(tfm_aes, tfm_cmac);
3828
3829 crypto_free_shash(tfm_cmac);
3830 crypto_free_cipher(tfm_aes);
3831
3832 return err;
3833}
3834
3835#endif