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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 <linux/debugfs.h>
24#include <linux/scatterlist.h>
25#include <crypto/b128ops.h>
26#include <crypto/hash.h>
27#include <crypto/skcipher.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 0x1f : 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};
80
81struct smp_dev {
82 /* Secure Connections OOB data */
83 u8 local_pk[64];
84 u8 local_sk[32];
85 u8 local_rand[16];
86 bool debug_key;
87
88 u8 min_key_size;
89 u8 max_key_size;
90
91 struct crypto_skcipher *tfm_aes;
92 struct crypto_shash *tfm_cmac;
93};
94
95struct smp_chan {
96 struct l2cap_conn *conn;
97 struct delayed_work security_timer;
98 unsigned long allow_cmd; /* Bitmask of allowed commands */
99
100 u8 preq[7]; /* SMP Pairing Request */
101 u8 prsp[7]; /* SMP Pairing Response */
102 u8 prnd[16]; /* SMP Pairing Random (local) */
103 u8 rrnd[16]; /* SMP Pairing Random (remote) */
104 u8 pcnf[16]; /* SMP Pairing Confirm */
105 u8 tk[16]; /* SMP Temporary Key */
106 u8 rr[16]; /* Remote OOB ra/rb value */
107 u8 lr[16]; /* Local OOB ra/rb value */
108 u8 enc_key_size;
109 u8 remote_key_dist;
110 bdaddr_t id_addr;
111 u8 id_addr_type;
112 u8 irk[16];
113 struct smp_csrk *csrk;
114 struct smp_csrk *slave_csrk;
115 struct smp_ltk *ltk;
116 struct smp_ltk *slave_ltk;
117 struct smp_irk *remote_irk;
118 u8 *link_key;
119 unsigned long flags;
120 u8 method;
121 u8 passkey_round;
122
123 /* Secure Connections variables */
124 u8 local_pk[64];
125 u8 local_sk[32];
126 u8 remote_pk[64];
127 u8 dhkey[32];
128 u8 mackey[16];
129
130 struct crypto_skcipher *tfm_aes;
131 struct crypto_shash *tfm_cmac;
132};
133
134/* These debug key values are defined in the SMP section of the core
135 * specification. debug_pk is the public debug key and debug_sk the
136 * private debug key.
137 */
138static const u8 debug_pk[64] = {
139 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
140 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
141 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
142 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20,
143
144 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74,
145 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76,
146 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63,
147 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc,
148};
149
150static const u8 debug_sk[32] = {
151 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58,
152 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a,
153 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74,
154 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f,
155};
156
157static inline void swap_buf(const u8 *src, u8 *dst, size_t len)
158{
159 size_t i;
160
161 for (i = 0; i < len; i++)
162 dst[len - 1 - i] = src[i];
163}
164
165/* The following functions map to the LE SC SMP crypto functions
166 * AES-CMAC, f4, f5, f6, g2 and h6.
167 */
168
169static int aes_cmac(struct crypto_shash *tfm, const u8 k[16], const u8 *m,
170 size_t len, u8 mac[16])
171{
172 uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX];
173 SHASH_DESC_ON_STACK(desc, tfm);
174 int err;
175
176 if (len > CMAC_MSG_MAX)
177 return -EFBIG;
178
179 if (!tfm) {
180 BT_ERR("tfm %p", tfm);
181 return -EINVAL;
182 }
183
184 desc->tfm = tfm;
185 desc->flags = 0;
186
187 /* Swap key and message from LSB to MSB */
188 swap_buf(k, tmp, 16);
189 swap_buf(m, msg_msb, len);
190
191 SMP_DBG("msg (len %zu) %*phN", len, (int) len, m);
192 SMP_DBG("key %16phN", k);
193
194 err = crypto_shash_setkey(tfm, tmp, 16);
195 if (err) {
196 BT_ERR("cipher setkey failed: %d", err);
197 return err;
198 }
199
200 err = crypto_shash_digest(desc, msg_msb, len, mac_msb);
201 shash_desc_zero(desc);
202 if (err) {
203 BT_ERR("Hash computation error %d", err);
204 return err;
205 }
206
207 swap_buf(mac_msb, mac, 16);
208
209 SMP_DBG("mac %16phN", mac);
210
211 return 0;
212}
213
214static int smp_f4(struct crypto_shash *tfm_cmac, const u8 u[32],
215 const u8 v[32], const u8 x[16], u8 z, u8 res[16])
216{
217 u8 m[65];
218 int err;
219
220 SMP_DBG("u %32phN", u);
221 SMP_DBG("v %32phN", v);
222 SMP_DBG("x %16phN z %02x", x, z);
223
224 m[0] = z;
225 memcpy(m + 1, v, 32);
226 memcpy(m + 33, u, 32);
227
228 err = aes_cmac(tfm_cmac, x, m, sizeof(m), res);
229 if (err)
230 return err;
231
232 SMP_DBG("res %16phN", res);
233
234 return err;
235}
236
237static int smp_f5(struct crypto_shash *tfm_cmac, const u8 w[32],
238 const u8 n1[16], const u8 n2[16], const u8 a1[7],
239 const u8 a2[7], u8 mackey[16], u8 ltk[16])
240{
241 /* The btle, salt and length "magic" values are as defined in
242 * the SMP section of the Bluetooth core specification. In ASCII
243 * the btle value ends up being 'btle'. The salt is just a
244 * random number whereas length is the value 256 in little
245 * endian format.
246 */
247 const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 };
248 const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60,
249 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c };
250 const u8 length[2] = { 0x00, 0x01 };
251 u8 m[53], t[16];
252 int err;
253
254 SMP_DBG("w %32phN", w);
255 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
256 SMP_DBG("a1 %7phN a2 %7phN", a1, a2);
257
258 err = aes_cmac(tfm_cmac, salt, w, 32, t);
259 if (err)
260 return err;
261
262 SMP_DBG("t %16phN", t);
263
264 memcpy(m, length, 2);
265 memcpy(m + 2, a2, 7);
266 memcpy(m + 9, a1, 7);
267 memcpy(m + 16, n2, 16);
268 memcpy(m + 32, n1, 16);
269 memcpy(m + 48, btle, 4);
270
271 m[52] = 0; /* Counter */
272
273 err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey);
274 if (err)
275 return err;
276
277 SMP_DBG("mackey %16phN", mackey);
278
279 m[52] = 1; /* Counter */
280
281 err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk);
282 if (err)
283 return err;
284
285 SMP_DBG("ltk %16phN", ltk);
286
287 return 0;
288}
289
290static int smp_f6(struct crypto_shash *tfm_cmac, const u8 w[16],
291 const u8 n1[16], const u8 n2[16], const u8 r[16],
292 const u8 io_cap[3], const u8 a1[7], const u8 a2[7],
293 u8 res[16])
294{
295 u8 m[65];
296 int err;
297
298 SMP_DBG("w %16phN", w);
299 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
300 SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2);
301
302 memcpy(m, a2, 7);
303 memcpy(m + 7, a1, 7);
304 memcpy(m + 14, io_cap, 3);
305 memcpy(m + 17, r, 16);
306 memcpy(m + 33, n2, 16);
307 memcpy(m + 49, n1, 16);
308
309 err = aes_cmac(tfm_cmac, w, m, sizeof(m), res);
310 if (err)
311 return err;
312
313 SMP_DBG("res %16phN", res);
314
315 return err;
316}
317
318static int smp_g2(struct crypto_shash *tfm_cmac, const u8 u[32], const u8 v[32],
319 const u8 x[16], const u8 y[16], u32 *val)
320{
321 u8 m[80], tmp[16];
322 int err;
323
324 SMP_DBG("u %32phN", u);
325 SMP_DBG("v %32phN", v);
326 SMP_DBG("x %16phN y %16phN", x, y);
327
328 memcpy(m, y, 16);
329 memcpy(m + 16, v, 32);
330 memcpy(m + 48, u, 32);
331
332 err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp);
333 if (err)
334 return err;
335
336 *val = get_unaligned_le32(tmp);
337 *val %= 1000000;
338
339 SMP_DBG("val %06u", *val);
340
341 return 0;
342}
343
344static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16],
345 const u8 key_id[4], u8 res[16])
346{
347 int err;
348
349 SMP_DBG("w %16phN key_id %4phN", w, key_id);
350
351 err = aes_cmac(tfm_cmac, w, key_id, 4, res);
352 if (err)
353 return err;
354
355 SMP_DBG("res %16phN", res);
356
357 return err;
358}
359
360/* The following functions map to the legacy SMP crypto functions e, c1,
361 * s1 and ah.
362 */
363
364static int smp_e(struct crypto_skcipher *tfm, const u8 *k, u8 *r)
365{
366 SKCIPHER_REQUEST_ON_STACK(req, tfm);
367 struct scatterlist sg;
368 uint8_t tmp[16], data[16];
369 int err;
370
371 SMP_DBG("k %16phN r %16phN", k, r);
372
373 if (!tfm) {
374 BT_ERR("tfm %p", tfm);
375 return -EINVAL;
376 }
377
378 /* The most significant octet of key corresponds to k[0] */
379 swap_buf(k, tmp, 16);
380
381 err = crypto_skcipher_setkey(tfm, tmp, 16);
382 if (err) {
383 BT_ERR("cipher setkey failed: %d", err);
384 return err;
385 }
386
387 /* Most significant octet of plaintextData corresponds to data[0] */
388 swap_buf(r, data, 16);
389
390 sg_init_one(&sg, data, 16);
391
392 skcipher_request_set_tfm(req, tfm);
393 skcipher_request_set_callback(req, 0, NULL, NULL);
394 skcipher_request_set_crypt(req, &sg, &sg, 16, NULL);
395
396 err = crypto_skcipher_encrypt(req);
397 skcipher_request_zero(req);
398 if (err)
399 BT_ERR("Encrypt data error %d", err);
400
401 /* Most significant octet of encryptedData corresponds to data[0] */
402 swap_buf(data, r, 16);
403
404 SMP_DBG("r %16phN", r);
405
406 return err;
407}
408
409static int smp_c1(struct crypto_skcipher *tfm_aes, const u8 k[16],
410 const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat,
411 const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16])
412{
413 u8 p1[16], p2[16];
414 int err;
415
416 SMP_DBG("k %16phN r %16phN", k, r);
417 SMP_DBG("iat %u ia %6phN rat %u ra %6phN", _iat, ia, _rat, ra);
418 SMP_DBG("preq %7phN pres %7phN", preq, pres);
419
420 memset(p1, 0, 16);
421
422 /* p1 = pres || preq || _rat || _iat */
423 p1[0] = _iat;
424 p1[1] = _rat;
425 memcpy(p1 + 2, preq, 7);
426 memcpy(p1 + 9, pres, 7);
427
428 SMP_DBG("p1 %16phN", p1);
429
430 /* res = r XOR p1 */
431 u128_xor((u128 *) res, (u128 *) r, (u128 *) p1);
432
433 /* res = e(k, res) */
434 err = smp_e(tfm_aes, k, res);
435 if (err) {
436 BT_ERR("Encrypt data error");
437 return err;
438 }
439
440 /* p2 = padding || ia || ra */
441 memcpy(p2, ra, 6);
442 memcpy(p2 + 6, ia, 6);
443 memset(p2 + 12, 0, 4);
444
445 SMP_DBG("p2 %16phN", p2);
446
447 /* res = res XOR p2 */
448 u128_xor((u128 *) res, (u128 *) res, (u128 *) p2);
449
450 /* res = e(k, res) */
451 err = smp_e(tfm_aes, k, res);
452 if (err)
453 BT_ERR("Encrypt data error");
454
455 return err;
456}
457
458static int smp_s1(struct crypto_skcipher *tfm_aes, const u8 k[16],
459 const u8 r1[16], const u8 r2[16], u8 _r[16])
460{
461 int err;
462
463 /* Just least significant octets from r1 and r2 are considered */
464 memcpy(_r, r2, 8);
465 memcpy(_r + 8, r1, 8);
466
467 err = smp_e(tfm_aes, k, _r);
468 if (err)
469 BT_ERR("Encrypt data error");
470
471 return err;
472}
473
474static int smp_ah(struct crypto_skcipher *tfm, const u8 irk[16],
475 const u8 r[3], u8 res[3])
476{
477 u8 _res[16];
478 int err;
479
480 /* r' = padding || r */
481 memcpy(_res, r, 3);
482 memset(_res + 3, 0, 13);
483
484 err = smp_e(tfm, irk, _res);
485 if (err) {
486 BT_ERR("Encrypt error");
487 return err;
488 }
489
490 /* The output of the random address function ah is:
491 * ah(k, r) = e(k, r') mod 2^24
492 * The output of the security function e is then truncated to 24 bits
493 * by taking the least significant 24 bits of the output of e as the
494 * result of ah.
495 */
496 memcpy(res, _res, 3);
497
498 return 0;
499}
500
501bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16],
502 const bdaddr_t *bdaddr)
503{
504 struct l2cap_chan *chan = hdev->smp_data;
505 struct smp_dev *smp;
506 u8 hash[3];
507 int err;
508
509 if (!chan || !chan->data)
510 return false;
511
512 smp = chan->data;
513
514 BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk);
515
516 err = smp_ah(smp->tfm_aes, irk, &bdaddr->b[3], hash);
517 if (err)
518 return false;
519
520 return !memcmp(bdaddr->b, hash, 3);
521}
522
523int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa)
524{
525 struct l2cap_chan *chan = hdev->smp_data;
526 struct smp_dev *smp;
527 int err;
528
529 if (!chan || !chan->data)
530 return -EOPNOTSUPP;
531
532 smp = chan->data;
533
534 get_random_bytes(&rpa->b[3], 3);
535
536 rpa->b[5] &= 0x3f; /* Clear two most significant bits */
537 rpa->b[5] |= 0x40; /* Set second most significant bit */
538
539 err = smp_ah(smp->tfm_aes, irk, &rpa->b[3], rpa->b);
540 if (err < 0)
541 return err;
542
543 BT_DBG("RPA %pMR", rpa);
544
545 return 0;
546}
547
548int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16])
549{
550 struct l2cap_chan *chan = hdev->smp_data;
551 struct smp_dev *smp;
552 int err;
553
554 if (!chan || !chan->data)
555 return -EOPNOTSUPP;
556
557 smp = chan->data;
558
559 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
560 BT_DBG("Using debug keys");
561 memcpy(smp->local_pk, debug_pk, 64);
562 memcpy(smp->local_sk, debug_sk, 32);
563 smp->debug_key = true;
564 } else {
565 while (true) {
566 /* Generate local key pair for Secure Connections */
567 if (!ecc_make_key(smp->local_pk, smp->local_sk))
568 return -EIO;
569
570 /* This is unlikely, but we need to check that
571 * we didn't accidentially generate a debug key.
572 */
573 if (memcmp(smp->local_sk, debug_sk, 32))
574 break;
575 }
576 smp->debug_key = false;
577 }
578
579 SMP_DBG("OOB Public Key X: %32phN", smp->local_pk);
580 SMP_DBG("OOB Public Key Y: %32phN", smp->local_pk + 32);
581 SMP_DBG("OOB Private Key: %32phN", smp->local_sk);
582
583 get_random_bytes(smp->local_rand, 16);
584
585 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->local_pk,
586 smp->local_rand, 0, hash);
587 if (err < 0)
588 return err;
589
590 memcpy(rand, smp->local_rand, 16);
591
592 return 0;
593}
594
595static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
596{
597 struct l2cap_chan *chan = conn->smp;
598 struct smp_chan *smp;
599 struct kvec iv[2];
600 struct msghdr msg;
601
602 if (!chan)
603 return;
604
605 BT_DBG("code 0x%2.2x", code);
606
607 iv[0].iov_base = &code;
608 iv[0].iov_len = 1;
609
610 iv[1].iov_base = data;
611 iv[1].iov_len = len;
612
613 memset(&msg, 0, sizeof(msg));
614
615 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iv, 2, 1 + len);
616
617 l2cap_chan_send(chan, &msg, 1 + len);
618
619 if (!chan->data)
620 return;
621
622 smp = chan->data;
623
624 cancel_delayed_work_sync(&smp->security_timer);
625 schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT);
626}
627
628static u8 authreq_to_seclevel(u8 authreq)
629{
630 if (authreq & SMP_AUTH_MITM) {
631 if (authreq & SMP_AUTH_SC)
632 return BT_SECURITY_FIPS;
633 else
634 return BT_SECURITY_HIGH;
635 } else {
636 return BT_SECURITY_MEDIUM;
637 }
638}
639
640static __u8 seclevel_to_authreq(__u8 sec_level)
641{
642 switch (sec_level) {
643 case BT_SECURITY_FIPS:
644 case BT_SECURITY_HIGH:
645 return SMP_AUTH_MITM | SMP_AUTH_BONDING;
646 case BT_SECURITY_MEDIUM:
647 return SMP_AUTH_BONDING;
648 default:
649 return SMP_AUTH_NONE;
650 }
651}
652
653static void build_pairing_cmd(struct l2cap_conn *conn,
654 struct smp_cmd_pairing *req,
655 struct smp_cmd_pairing *rsp, __u8 authreq)
656{
657 struct l2cap_chan *chan = conn->smp;
658 struct smp_chan *smp = chan->data;
659 struct hci_conn *hcon = conn->hcon;
660 struct hci_dev *hdev = hcon->hdev;
661 u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT;
662
663 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
664 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
665 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
666 authreq |= SMP_AUTH_BONDING;
667 } else {
668 authreq &= ~SMP_AUTH_BONDING;
669 }
670
671 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
672 remote_dist |= SMP_DIST_ID_KEY;
673
674 if (hci_dev_test_flag(hdev, HCI_PRIVACY))
675 local_dist |= SMP_DIST_ID_KEY;
676
677 if (hci_dev_test_flag(hdev, HCI_SC_ENABLED) &&
678 (authreq & SMP_AUTH_SC)) {
679 struct oob_data *oob_data;
680 u8 bdaddr_type;
681
682 if (hci_dev_test_flag(hdev, HCI_SSP_ENABLED)) {
683 local_dist |= SMP_DIST_LINK_KEY;
684 remote_dist |= SMP_DIST_LINK_KEY;
685 }
686
687 if (hcon->dst_type == ADDR_LE_DEV_PUBLIC)
688 bdaddr_type = BDADDR_LE_PUBLIC;
689 else
690 bdaddr_type = BDADDR_LE_RANDOM;
691
692 oob_data = hci_find_remote_oob_data(hdev, &hcon->dst,
693 bdaddr_type);
694 if (oob_data && oob_data->present) {
695 set_bit(SMP_FLAG_REMOTE_OOB, &smp->flags);
696 oob_flag = SMP_OOB_PRESENT;
697 memcpy(smp->rr, oob_data->rand256, 16);
698 memcpy(smp->pcnf, oob_data->hash256, 16);
699 SMP_DBG("OOB Remote Confirmation: %16phN", smp->pcnf);
700 SMP_DBG("OOB Remote Random: %16phN", smp->rr);
701 }
702
703 } else {
704 authreq &= ~SMP_AUTH_SC;
705 }
706
707 if (rsp == NULL) {
708 req->io_capability = conn->hcon->io_capability;
709 req->oob_flag = oob_flag;
710 req->max_key_size = SMP_DEV(hdev)->max_key_size;
711 req->init_key_dist = local_dist;
712 req->resp_key_dist = remote_dist;
713 req->auth_req = (authreq & AUTH_REQ_MASK(hdev));
714
715 smp->remote_key_dist = remote_dist;
716 return;
717 }
718
719 rsp->io_capability = conn->hcon->io_capability;
720 rsp->oob_flag = oob_flag;
721 rsp->max_key_size = SMP_DEV(hdev)->max_key_size;
722 rsp->init_key_dist = req->init_key_dist & remote_dist;
723 rsp->resp_key_dist = req->resp_key_dist & local_dist;
724 rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev));
725
726 smp->remote_key_dist = rsp->init_key_dist;
727}
728
729static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)
730{
731 struct l2cap_chan *chan = conn->smp;
732 struct hci_dev *hdev = conn->hcon->hdev;
733 struct smp_chan *smp = chan->data;
734
735 if (max_key_size > SMP_DEV(hdev)->max_key_size ||
736 max_key_size < SMP_MIN_ENC_KEY_SIZE)
737 return SMP_ENC_KEY_SIZE;
738
739 smp->enc_key_size = max_key_size;
740
741 return 0;
742}
743
744static void smp_chan_destroy(struct l2cap_conn *conn)
745{
746 struct l2cap_chan *chan = conn->smp;
747 struct smp_chan *smp = chan->data;
748 struct hci_conn *hcon = conn->hcon;
749 bool complete;
750
751 BUG_ON(!smp);
752
753 cancel_delayed_work_sync(&smp->security_timer);
754
755 complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags);
756 mgmt_smp_complete(hcon, complete);
757
758 kzfree(smp->csrk);
759 kzfree(smp->slave_csrk);
760 kzfree(smp->link_key);
761
762 crypto_free_skcipher(smp->tfm_aes);
763 crypto_free_shash(smp->tfm_cmac);
764
765 /* Ensure that we don't leave any debug key around if debug key
766 * support hasn't been explicitly enabled.
767 */
768 if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG &&
769 !hci_dev_test_flag(hcon->hdev, HCI_KEEP_DEBUG_KEYS)) {
770 list_del_rcu(&smp->ltk->list);
771 kfree_rcu(smp->ltk, rcu);
772 smp->ltk = NULL;
773 }
774
775 /* If pairing failed clean up any keys we might have */
776 if (!complete) {
777 if (smp->ltk) {
778 list_del_rcu(&smp->ltk->list);
779 kfree_rcu(smp->ltk, rcu);
780 }
781
782 if (smp->slave_ltk) {
783 list_del_rcu(&smp->slave_ltk->list);
784 kfree_rcu(smp->slave_ltk, rcu);
785 }
786
787 if (smp->remote_irk) {
788 list_del_rcu(&smp->remote_irk->list);
789 kfree_rcu(smp->remote_irk, rcu);
790 }
791 }
792
793 chan->data = NULL;
794 kzfree(smp);
795 hci_conn_drop(hcon);
796}
797
798static void smp_failure(struct l2cap_conn *conn, u8 reason)
799{
800 struct hci_conn *hcon = conn->hcon;
801 struct l2cap_chan *chan = conn->smp;
802
803 if (reason)
804 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
805 &reason);
806
807 mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE);
808
809 if (chan->data)
810 smp_chan_destroy(conn);
811}
812
813#define JUST_WORKS 0x00
814#define JUST_CFM 0x01
815#define REQ_PASSKEY 0x02
816#define CFM_PASSKEY 0x03
817#define REQ_OOB 0x04
818#define DSP_PASSKEY 0x05
819#define OVERLAP 0xFF
820
821static const u8 gen_method[5][5] = {
822 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
823 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
824 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
825 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
826 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP },
827};
828
829static const u8 sc_method[5][5] = {
830 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
831 { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
832 { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY },
833 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
834 { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
835};
836
837static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io)
838{
839 /* If either side has unknown io_caps, use JUST_CFM (which gets
840 * converted later to JUST_WORKS if we're initiators.
841 */
842 if (local_io > SMP_IO_KEYBOARD_DISPLAY ||
843 remote_io > SMP_IO_KEYBOARD_DISPLAY)
844 return JUST_CFM;
845
846 if (test_bit(SMP_FLAG_SC, &smp->flags))
847 return sc_method[remote_io][local_io];
848
849 return gen_method[remote_io][local_io];
850}
851
852static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
853 u8 local_io, u8 remote_io)
854{
855 struct hci_conn *hcon = conn->hcon;
856 struct l2cap_chan *chan = conn->smp;
857 struct smp_chan *smp = chan->data;
858 u32 passkey = 0;
859 int ret = 0;
860
861 /* Initialize key for JUST WORKS */
862 memset(smp->tk, 0, sizeof(smp->tk));
863 clear_bit(SMP_FLAG_TK_VALID, &smp->flags);
864
865 BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io);
866
867 /* If neither side wants MITM, either "just" confirm an incoming
868 * request or use just-works for outgoing ones. The JUST_CFM
869 * will be converted to JUST_WORKS if necessary later in this
870 * function. If either side has MITM look up the method from the
871 * table.
872 */
873 if (!(auth & SMP_AUTH_MITM))
874 smp->method = JUST_CFM;
875 else
876 smp->method = get_auth_method(smp, local_io, remote_io);
877
878 /* Don't confirm locally initiated pairing attempts */
879 if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR,
880 &smp->flags))
881 smp->method = JUST_WORKS;
882
883 /* Don't bother user space with no IO capabilities */
884 if (smp->method == JUST_CFM &&
885 hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
886 smp->method = JUST_WORKS;
887
888 /* If Just Works, Continue with Zero TK */
889 if (smp->method == JUST_WORKS) {
890 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
891 return 0;
892 }
893
894 /* If this function is used for SC -> legacy fallback we
895 * can only recover the just-works case.
896 */
897 if (test_bit(SMP_FLAG_SC, &smp->flags))
898 return -EINVAL;
899
900 /* Not Just Works/Confirm results in MITM Authentication */
901 if (smp->method != JUST_CFM) {
902 set_bit(SMP_FLAG_MITM_AUTH, &smp->flags);
903 if (hcon->pending_sec_level < BT_SECURITY_HIGH)
904 hcon->pending_sec_level = BT_SECURITY_HIGH;
905 }
906
907 /* If both devices have Keyoard-Display I/O, the master
908 * Confirms and the slave Enters the passkey.
909 */
910 if (smp->method == OVERLAP) {
911 if (hcon->role == HCI_ROLE_MASTER)
912 smp->method = CFM_PASSKEY;
913 else
914 smp->method = REQ_PASSKEY;
915 }
916
917 /* Generate random passkey. */
918 if (smp->method == CFM_PASSKEY) {
919 memset(smp->tk, 0, sizeof(smp->tk));
920 get_random_bytes(&passkey, sizeof(passkey));
921 passkey %= 1000000;
922 put_unaligned_le32(passkey, smp->tk);
923 BT_DBG("PassKey: %d", passkey);
924 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
925 }
926
927 if (smp->method == REQ_PASSKEY)
928 ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst,
929 hcon->type, hcon->dst_type);
930 else if (smp->method == JUST_CFM)
931 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
932 hcon->type, hcon->dst_type,
933 passkey, 1);
934 else
935 ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst,
936 hcon->type, hcon->dst_type,
937 passkey, 0);
938
939 return ret;
940}
941
942static u8 smp_confirm(struct smp_chan *smp)
943{
944 struct l2cap_conn *conn = smp->conn;
945 struct smp_cmd_pairing_confirm cp;
946 int ret;
947
948 BT_DBG("conn %p", conn);
949
950 ret = smp_c1(smp->tfm_aes, smp->tk, smp->prnd, smp->preq, smp->prsp,
951 conn->hcon->init_addr_type, &conn->hcon->init_addr,
952 conn->hcon->resp_addr_type, &conn->hcon->resp_addr,
953 cp.confirm_val);
954 if (ret)
955 return SMP_UNSPECIFIED;
956
957 clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
958
959 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
960
961 if (conn->hcon->out)
962 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
963 else
964 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
965
966 return 0;
967}
968
969static u8 smp_random(struct smp_chan *smp)
970{
971 struct l2cap_conn *conn = smp->conn;
972 struct hci_conn *hcon = conn->hcon;
973 u8 confirm[16];
974 int ret;
975
976 if (IS_ERR_OR_NULL(smp->tfm_aes))
977 return SMP_UNSPECIFIED;
978
979 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
980
981 ret = smp_c1(smp->tfm_aes, smp->tk, smp->rrnd, smp->preq, smp->prsp,
982 hcon->init_addr_type, &hcon->init_addr,
983 hcon->resp_addr_type, &hcon->resp_addr, confirm);
984 if (ret)
985 return SMP_UNSPECIFIED;
986
987 if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) {
988 BT_ERR("Pairing failed (confirmation values mismatch)");
989 return SMP_CONFIRM_FAILED;
990 }
991
992 if (hcon->out) {
993 u8 stk[16];
994 __le64 rand = 0;
995 __le16 ediv = 0;
996
997 smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk);
998
999 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
1000 return SMP_UNSPECIFIED;
1001
1002 hci_le_start_enc(hcon, ediv, rand, stk, smp->enc_key_size);
1003 hcon->enc_key_size = smp->enc_key_size;
1004 set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
1005 } else {
1006 u8 stk[16], auth;
1007 __le64 rand = 0;
1008 __le16 ediv = 0;
1009
1010 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1011 smp->prnd);
1012
1013 smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk);
1014
1015 if (hcon->pending_sec_level == BT_SECURITY_HIGH)
1016 auth = 1;
1017 else
1018 auth = 0;
1019
1020 /* Even though there's no _SLAVE suffix this is the
1021 * slave STK we're adding for later lookup (the master
1022 * STK never needs to be stored).
1023 */
1024 hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1025 SMP_STK, auth, stk, smp->enc_key_size, ediv, rand);
1026 }
1027
1028 return 0;
1029}
1030
1031static void smp_notify_keys(struct l2cap_conn *conn)
1032{
1033 struct l2cap_chan *chan = conn->smp;
1034 struct smp_chan *smp = chan->data;
1035 struct hci_conn *hcon = conn->hcon;
1036 struct hci_dev *hdev = hcon->hdev;
1037 struct smp_cmd_pairing *req = (void *) &smp->preq[1];
1038 struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1];
1039 bool persistent;
1040
1041 if (hcon->type == ACL_LINK) {
1042 if (hcon->key_type == HCI_LK_DEBUG_COMBINATION)
1043 persistent = false;
1044 else
1045 persistent = !test_bit(HCI_CONN_FLUSH_KEY,
1046 &hcon->flags);
1047 } else {
1048 /* The LTKs, IRKs and CSRKs should be persistent only if
1049 * both sides had the bonding bit set in their
1050 * authentication requests.
1051 */
1052 persistent = !!((req->auth_req & rsp->auth_req) &
1053 SMP_AUTH_BONDING);
1054 }
1055
1056 if (smp->remote_irk) {
1057 mgmt_new_irk(hdev, smp->remote_irk, persistent);
1058
1059 /* Now that user space can be considered to know the
1060 * identity address track the connection based on it
1061 * from now on (assuming this is an LE link).
1062 */
1063 if (hcon->type == LE_LINK) {
1064 bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
1065 hcon->dst_type = smp->remote_irk->addr_type;
1066 queue_work(hdev->workqueue, &conn->id_addr_update_work);
1067 }
1068 }
1069
1070 if (smp->csrk) {
1071 smp->csrk->bdaddr_type = hcon->dst_type;
1072 bacpy(&smp->csrk->bdaddr, &hcon->dst);
1073 mgmt_new_csrk(hdev, smp->csrk, persistent);
1074 }
1075
1076 if (smp->slave_csrk) {
1077 smp->slave_csrk->bdaddr_type = hcon->dst_type;
1078 bacpy(&smp->slave_csrk->bdaddr, &hcon->dst);
1079 mgmt_new_csrk(hdev, smp->slave_csrk, persistent);
1080 }
1081
1082 if (smp->ltk) {
1083 smp->ltk->bdaddr_type = hcon->dst_type;
1084 bacpy(&smp->ltk->bdaddr, &hcon->dst);
1085 mgmt_new_ltk(hdev, smp->ltk, persistent);
1086 }
1087
1088 if (smp->slave_ltk) {
1089 smp->slave_ltk->bdaddr_type = hcon->dst_type;
1090 bacpy(&smp->slave_ltk->bdaddr, &hcon->dst);
1091 mgmt_new_ltk(hdev, smp->slave_ltk, persistent);
1092 }
1093
1094 if (smp->link_key) {
1095 struct link_key *key;
1096 u8 type;
1097
1098 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1099 type = HCI_LK_DEBUG_COMBINATION;
1100 else if (hcon->sec_level == BT_SECURITY_FIPS)
1101 type = HCI_LK_AUTH_COMBINATION_P256;
1102 else
1103 type = HCI_LK_UNAUTH_COMBINATION_P256;
1104
1105 key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst,
1106 smp->link_key, type, 0, &persistent);
1107 if (key) {
1108 mgmt_new_link_key(hdev, key, persistent);
1109
1110 /* Don't keep debug keys around if the relevant
1111 * flag is not set.
1112 */
1113 if (!hci_dev_test_flag(hdev, HCI_KEEP_DEBUG_KEYS) &&
1114 key->type == HCI_LK_DEBUG_COMBINATION) {
1115 list_del_rcu(&key->list);
1116 kfree_rcu(key, rcu);
1117 }
1118 }
1119 }
1120}
1121
1122static void sc_add_ltk(struct smp_chan *smp)
1123{
1124 struct hci_conn *hcon = smp->conn->hcon;
1125 u8 key_type, auth;
1126
1127 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1128 key_type = SMP_LTK_P256_DEBUG;
1129 else
1130 key_type = SMP_LTK_P256;
1131
1132 if (hcon->pending_sec_level == BT_SECURITY_FIPS)
1133 auth = 1;
1134 else
1135 auth = 0;
1136
1137 smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1138 key_type, auth, smp->tk, smp->enc_key_size,
1139 0, 0);
1140}
1141
1142static void sc_generate_link_key(struct smp_chan *smp)
1143{
1144 /* These constants are as specified in the core specification.
1145 * In ASCII they spell out to 'tmp1' and 'lebr'.
1146 */
1147 const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 };
1148 const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c };
1149
1150 smp->link_key = kzalloc(16, GFP_KERNEL);
1151 if (!smp->link_key)
1152 return;
1153
1154 if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) {
1155 kzfree(smp->link_key);
1156 smp->link_key = NULL;
1157 return;
1158 }
1159
1160 if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) {
1161 kzfree(smp->link_key);
1162 smp->link_key = NULL;
1163 return;
1164 }
1165}
1166
1167static void smp_allow_key_dist(struct smp_chan *smp)
1168{
1169 /* Allow the first expected phase 3 PDU. The rest of the PDUs
1170 * will be allowed in each PDU handler to ensure we receive
1171 * them in the correct order.
1172 */
1173 if (smp->remote_key_dist & SMP_DIST_ENC_KEY)
1174 SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO);
1175 else if (smp->remote_key_dist & SMP_DIST_ID_KEY)
1176 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
1177 else if (smp->remote_key_dist & SMP_DIST_SIGN)
1178 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
1179}
1180
1181static void sc_generate_ltk(struct smp_chan *smp)
1182{
1183 /* These constants are as specified in the core specification.
1184 * In ASCII they spell out to 'tmp2' and 'brle'.
1185 */
1186 const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 };
1187 const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 };
1188 struct hci_conn *hcon = smp->conn->hcon;
1189 struct hci_dev *hdev = hcon->hdev;
1190 struct link_key *key;
1191
1192 key = hci_find_link_key(hdev, &hcon->dst);
1193 if (!key) {
1194 BT_ERR("%s No Link Key found to generate LTK", hdev->name);
1195 return;
1196 }
1197
1198 if (key->type == HCI_LK_DEBUG_COMBINATION)
1199 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1200
1201 if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk))
1202 return;
1203
1204 if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk))
1205 return;
1206
1207 sc_add_ltk(smp);
1208}
1209
1210static void smp_distribute_keys(struct smp_chan *smp)
1211{
1212 struct smp_cmd_pairing *req, *rsp;
1213 struct l2cap_conn *conn = smp->conn;
1214 struct hci_conn *hcon = conn->hcon;
1215 struct hci_dev *hdev = hcon->hdev;
1216 __u8 *keydist;
1217
1218 BT_DBG("conn %p", conn);
1219
1220 rsp = (void *) &smp->prsp[1];
1221
1222 /* The responder sends its keys first */
1223 if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) {
1224 smp_allow_key_dist(smp);
1225 return;
1226 }
1227
1228 req = (void *) &smp->preq[1];
1229
1230 if (hcon->out) {
1231 keydist = &rsp->init_key_dist;
1232 *keydist &= req->init_key_dist;
1233 } else {
1234 keydist = &rsp->resp_key_dist;
1235 *keydist &= req->resp_key_dist;
1236 }
1237
1238 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1239 if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY))
1240 sc_generate_link_key(smp);
1241 if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY))
1242 sc_generate_ltk(smp);
1243
1244 /* Clear the keys which are generated but not distributed */
1245 *keydist &= ~SMP_SC_NO_DIST;
1246 }
1247
1248 BT_DBG("keydist 0x%x", *keydist);
1249
1250 if (*keydist & SMP_DIST_ENC_KEY) {
1251 struct smp_cmd_encrypt_info enc;
1252 struct smp_cmd_master_ident ident;
1253 struct smp_ltk *ltk;
1254 u8 authenticated;
1255 __le16 ediv;
1256 __le64 rand;
1257
1258 /* Make sure we generate only the significant amount of
1259 * bytes based on the encryption key size, and set the rest
1260 * of the value to zeroes.
1261 */
1262 get_random_bytes(enc.ltk, smp->enc_key_size);
1263 memset(enc.ltk + smp->enc_key_size, 0,
1264 sizeof(enc.ltk) - smp->enc_key_size);
1265
1266 get_random_bytes(&ediv, sizeof(ediv));
1267 get_random_bytes(&rand, sizeof(rand));
1268
1269 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);
1270
1271 authenticated = hcon->sec_level == BT_SECURITY_HIGH;
1272 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type,
1273 SMP_LTK_SLAVE, authenticated, enc.ltk,
1274 smp->enc_key_size, ediv, rand);
1275 smp->slave_ltk = ltk;
1276
1277 ident.ediv = ediv;
1278 ident.rand = rand;
1279
1280 smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident);
1281
1282 *keydist &= ~SMP_DIST_ENC_KEY;
1283 }
1284
1285 if (*keydist & SMP_DIST_ID_KEY) {
1286 struct smp_cmd_ident_addr_info addrinfo;
1287 struct smp_cmd_ident_info idinfo;
1288
1289 memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk));
1290
1291 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);
1292
1293 /* The hci_conn contains the local identity address
1294 * after the connection has been established.
1295 *
1296 * This is true even when the connection has been
1297 * established using a resolvable random address.
1298 */
1299 bacpy(&addrinfo.bdaddr, &hcon->src);
1300 addrinfo.addr_type = hcon->src_type;
1301
1302 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo),
1303 &addrinfo);
1304
1305 *keydist &= ~SMP_DIST_ID_KEY;
1306 }
1307
1308 if (*keydist & SMP_DIST_SIGN) {
1309 struct smp_cmd_sign_info sign;
1310 struct smp_csrk *csrk;
1311
1312 /* Generate a new random key */
1313 get_random_bytes(sign.csrk, sizeof(sign.csrk));
1314
1315 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
1316 if (csrk) {
1317 if (hcon->sec_level > BT_SECURITY_MEDIUM)
1318 csrk->type = MGMT_CSRK_LOCAL_AUTHENTICATED;
1319 else
1320 csrk->type = MGMT_CSRK_LOCAL_UNAUTHENTICATED;
1321 memcpy(csrk->val, sign.csrk, sizeof(csrk->val));
1322 }
1323 smp->slave_csrk = csrk;
1324
1325 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);
1326
1327 *keydist &= ~SMP_DIST_SIGN;
1328 }
1329
1330 /* If there are still keys to be received wait for them */
1331 if (smp->remote_key_dist & KEY_DIST_MASK) {
1332 smp_allow_key_dist(smp);
1333 return;
1334 }
1335
1336 set_bit(SMP_FLAG_COMPLETE, &smp->flags);
1337 smp_notify_keys(conn);
1338
1339 smp_chan_destroy(conn);
1340}
1341
1342static void smp_timeout(struct work_struct *work)
1343{
1344 struct smp_chan *smp = container_of(work, struct smp_chan,
1345 security_timer.work);
1346 struct l2cap_conn *conn = smp->conn;
1347
1348 BT_DBG("conn %p", conn);
1349
1350 hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM);
1351}
1352
1353static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
1354{
1355 struct l2cap_chan *chan = conn->smp;
1356 struct smp_chan *smp;
1357
1358 smp = kzalloc(sizeof(*smp), GFP_ATOMIC);
1359 if (!smp)
1360 return NULL;
1361
1362 smp->tfm_aes = crypto_alloc_skcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
1363 if (IS_ERR(smp->tfm_aes)) {
1364 BT_ERR("Unable to create ECB crypto context");
1365 kzfree(smp);
1366 return NULL;
1367 }
1368
1369 smp->tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
1370 if (IS_ERR(smp->tfm_cmac)) {
1371 BT_ERR("Unable to create CMAC crypto context");
1372 crypto_free_skcipher(smp->tfm_aes);
1373 kzfree(smp);
1374 return NULL;
1375 }
1376
1377 smp->conn = conn;
1378 chan->data = smp;
1379
1380 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL);
1381
1382 INIT_DELAYED_WORK(&smp->security_timer, smp_timeout);
1383
1384 hci_conn_hold(conn->hcon);
1385
1386 return smp;
1387}
1388
1389static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16])
1390{
1391 struct hci_conn *hcon = smp->conn->hcon;
1392 u8 *na, *nb, a[7], b[7];
1393
1394 if (hcon->out) {
1395 na = smp->prnd;
1396 nb = smp->rrnd;
1397 } else {
1398 na = smp->rrnd;
1399 nb = smp->prnd;
1400 }
1401
1402 memcpy(a, &hcon->init_addr, 6);
1403 memcpy(b, &hcon->resp_addr, 6);
1404 a[6] = hcon->init_addr_type;
1405 b[6] = hcon->resp_addr_type;
1406
1407 return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk);
1408}
1409
1410static void sc_dhkey_check(struct smp_chan *smp)
1411{
1412 struct hci_conn *hcon = smp->conn->hcon;
1413 struct smp_cmd_dhkey_check check;
1414 u8 a[7], b[7], *local_addr, *remote_addr;
1415 u8 io_cap[3], r[16];
1416
1417 memcpy(a, &hcon->init_addr, 6);
1418 memcpy(b, &hcon->resp_addr, 6);
1419 a[6] = hcon->init_addr_type;
1420 b[6] = hcon->resp_addr_type;
1421
1422 if (hcon->out) {
1423 local_addr = a;
1424 remote_addr = b;
1425 memcpy(io_cap, &smp->preq[1], 3);
1426 } else {
1427 local_addr = b;
1428 remote_addr = a;
1429 memcpy(io_cap, &smp->prsp[1], 3);
1430 }
1431
1432 memset(r, 0, sizeof(r));
1433
1434 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
1435 put_unaligned_le32(hcon->passkey_notify, r);
1436
1437 if (smp->method == REQ_OOB)
1438 memcpy(r, smp->rr, 16);
1439
1440 smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap,
1441 local_addr, remote_addr, check.e);
1442
1443 smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check);
1444}
1445
1446static u8 sc_passkey_send_confirm(struct smp_chan *smp)
1447{
1448 struct l2cap_conn *conn = smp->conn;
1449 struct hci_conn *hcon = conn->hcon;
1450 struct smp_cmd_pairing_confirm cfm;
1451 u8 r;
1452
1453 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1454 r |= 0x80;
1455
1456 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1457
1458 if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r,
1459 cfm.confirm_val))
1460 return SMP_UNSPECIFIED;
1461
1462 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
1463
1464 return 0;
1465}
1466
1467static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op)
1468{
1469 struct l2cap_conn *conn = smp->conn;
1470 struct hci_conn *hcon = conn->hcon;
1471 struct hci_dev *hdev = hcon->hdev;
1472 u8 cfm[16], r;
1473
1474 /* Ignore the PDU if we've already done 20 rounds (0 - 19) */
1475 if (smp->passkey_round >= 20)
1476 return 0;
1477
1478 switch (smp_op) {
1479 case SMP_CMD_PAIRING_RANDOM:
1480 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1481 r |= 0x80;
1482
1483 if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
1484 smp->rrnd, r, cfm))
1485 return SMP_UNSPECIFIED;
1486
1487 if (memcmp(smp->pcnf, cfm, 16))
1488 return SMP_CONFIRM_FAILED;
1489
1490 smp->passkey_round++;
1491
1492 if (smp->passkey_round == 20) {
1493 /* Generate MacKey and LTK */
1494 if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk))
1495 return SMP_UNSPECIFIED;
1496 }
1497
1498 /* The round is only complete when the initiator
1499 * receives pairing random.
1500 */
1501 if (!hcon->out) {
1502 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1503 sizeof(smp->prnd), smp->prnd);
1504 if (smp->passkey_round == 20)
1505 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1506 else
1507 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1508 return 0;
1509 }
1510
1511 /* Start the next round */
1512 if (smp->passkey_round != 20)
1513 return sc_passkey_round(smp, 0);
1514
1515 /* Passkey rounds are complete - start DHKey Check */
1516 sc_dhkey_check(smp);
1517 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1518
1519 break;
1520
1521 case SMP_CMD_PAIRING_CONFIRM:
1522 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
1523 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
1524 return 0;
1525 }
1526
1527 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1528
1529 if (hcon->out) {
1530 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1531 sizeof(smp->prnd), smp->prnd);
1532 return 0;
1533 }
1534
1535 return sc_passkey_send_confirm(smp);
1536
1537 case SMP_CMD_PUBLIC_KEY:
1538 default:
1539 /* Initiating device starts the round */
1540 if (!hcon->out)
1541 return 0;
1542
1543 BT_DBG("%s Starting passkey round %u", hdev->name,
1544 smp->passkey_round + 1);
1545
1546 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1547
1548 return sc_passkey_send_confirm(smp);
1549 }
1550
1551 return 0;
1552}
1553
1554static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey)
1555{
1556 struct l2cap_conn *conn = smp->conn;
1557 struct hci_conn *hcon = conn->hcon;
1558 u8 smp_op;
1559
1560 clear_bit(SMP_FLAG_WAIT_USER, &smp->flags);
1561
1562 switch (mgmt_op) {
1563 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1564 smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED);
1565 return 0;
1566 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1567 smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED);
1568 return 0;
1569 case MGMT_OP_USER_PASSKEY_REPLY:
1570 hcon->passkey_notify = le32_to_cpu(passkey);
1571 smp->passkey_round = 0;
1572
1573 if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags))
1574 smp_op = SMP_CMD_PAIRING_CONFIRM;
1575 else
1576 smp_op = 0;
1577
1578 if (sc_passkey_round(smp, smp_op))
1579 return -EIO;
1580
1581 return 0;
1582 }
1583
1584 /* Initiator sends DHKey check first */
1585 if (hcon->out) {
1586 sc_dhkey_check(smp);
1587 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1588 } else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) {
1589 sc_dhkey_check(smp);
1590 sc_add_ltk(smp);
1591 }
1592
1593 return 0;
1594}
1595
1596int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
1597{
1598 struct l2cap_conn *conn = hcon->l2cap_data;
1599 struct l2cap_chan *chan;
1600 struct smp_chan *smp;
1601 u32 value;
1602 int err;
1603
1604 BT_DBG("");
1605
1606 if (!conn)
1607 return -ENOTCONN;
1608
1609 chan = conn->smp;
1610 if (!chan)
1611 return -ENOTCONN;
1612
1613 l2cap_chan_lock(chan);
1614 if (!chan->data) {
1615 err = -ENOTCONN;
1616 goto unlock;
1617 }
1618
1619 smp = chan->data;
1620
1621 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1622 err = sc_user_reply(smp, mgmt_op, passkey);
1623 goto unlock;
1624 }
1625
1626 switch (mgmt_op) {
1627 case MGMT_OP_USER_PASSKEY_REPLY:
1628 value = le32_to_cpu(passkey);
1629 memset(smp->tk, 0, sizeof(smp->tk));
1630 BT_DBG("PassKey: %d", value);
1631 put_unaligned_le32(value, smp->tk);
1632 /* Fall Through */
1633 case MGMT_OP_USER_CONFIRM_REPLY:
1634 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
1635 break;
1636 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1637 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1638 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1639 err = 0;
1640 goto unlock;
1641 default:
1642 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1643 err = -EOPNOTSUPP;
1644 goto unlock;
1645 }
1646
1647 err = 0;
1648
1649 /* If it is our turn to send Pairing Confirm, do so now */
1650 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) {
1651 u8 rsp = smp_confirm(smp);
1652 if (rsp)
1653 smp_failure(conn, rsp);
1654 }
1655
1656unlock:
1657 l2cap_chan_unlock(chan);
1658 return err;
1659}
1660
1661static void build_bredr_pairing_cmd(struct smp_chan *smp,
1662 struct smp_cmd_pairing *req,
1663 struct smp_cmd_pairing *rsp)
1664{
1665 struct l2cap_conn *conn = smp->conn;
1666 struct hci_dev *hdev = conn->hcon->hdev;
1667 u8 local_dist = 0, remote_dist = 0;
1668
1669 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
1670 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1671 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1672 }
1673
1674 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
1675 remote_dist |= SMP_DIST_ID_KEY;
1676
1677 if (hci_dev_test_flag(hdev, HCI_PRIVACY))
1678 local_dist |= SMP_DIST_ID_KEY;
1679
1680 if (!rsp) {
1681 memset(req, 0, sizeof(*req));
1682
1683 req->init_key_dist = local_dist;
1684 req->resp_key_dist = remote_dist;
1685 req->max_key_size = conn->hcon->enc_key_size;
1686
1687 smp->remote_key_dist = remote_dist;
1688
1689 return;
1690 }
1691
1692 memset(rsp, 0, sizeof(*rsp));
1693
1694 rsp->max_key_size = conn->hcon->enc_key_size;
1695 rsp->init_key_dist = req->init_key_dist & remote_dist;
1696 rsp->resp_key_dist = req->resp_key_dist & local_dist;
1697
1698 smp->remote_key_dist = rsp->init_key_dist;
1699}
1700
1701static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
1702{
1703 struct smp_cmd_pairing rsp, *req = (void *) skb->data;
1704 struct l2cap_chan *chan = conn->smp;
1705 struct hci_dev *hdev = conn->hcon->hdev;
1706 struct smp_chan *smp;
1707 u8 key_size, auth, sec_level;
1708 int ret;
1709
1710 BT_DBG("conn %p", conn);
1711
1712 if (skb->len < sizeof(*req))
1713 return SMP_INVALID_PARAMS;
1714
1715 if (conn->hcon->role != HCI_ROLE_SLAVE)
1716 return SMP_CMD_NOTSUPP;
1717
1718 if (!chan->data)
1719 smp = smp_chan_create(conn);
1720 else
1721 smp = chan->data;
1722
1723 if (!smp)
1724 return SMP_UNSPECIFIED;
1725
1726 /* We didn't start the pairing, so match remote */
1727 auth = req->auth_req & AUTH_REQ_MASK(hdev);
1728
1729 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
1730 (auth & SMP_AUTH_BONDING))
1731 return SMP_PAIRING_NOTSUPP;
1732
1733 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1734 return SMP_AUTH_REQUIREMENTS;
1735
1736 smp->preq[0] = SMP_CMD_PAIRING_REQ;
1737 memcpy(&smp->preq[1], req, sizeof(*req));
1738 skb_pull(skb, sizeof(*req));
1739
1740 /* If the remote side's OOB flag is set it means it has
1741 * successfully received our local OOB data - therefore set the
1742 * flag to indicate that local OOB is in use.
1743 */
1744 if (req->oob_flag == SMP_OOB_PRESENT)
1745 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1746
1747 /* SMP over BR/EDR requires special treatment */
1748 if (conn->hcon->type == ACL_LINK) {
1749 /* We must have a BR/EDR SC link */
1750 if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) &&
1751 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
1752 return SMP_CROSS_TRANSP_NOT_ALLOWED;
1753
1754 set_bit(SMP_FLAG_SC, &smp->flags);
1755
1756 build_bredr_pairing_cmd(smp, req, &rsp);
1757
1758 key_size = min(req->max_key_size, rsp.max_key_size);
1759 if (check_enc_key_size(conn, key_size))
1760 return SMP_ENC_KEY_SIZE;
1761
1762 /* Clear bits which are generated but not distributed */
1763 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1764
1765 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1766 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1767 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1768
1769 smp_distribute_keys(smp);
1770 return 0;
1771 }
1772
1773 build_pairing_cmd(conn, req, &rsp, auth);
1774
1775 if (rsp.auth_req & SMP_AUTH_SC)
1776 set_bit(SMP_FLAG_SC, &smp->flags);
1777
1778 if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
1779 sec_level = BT_SECURITY_MEDIUM;
1780 else
1781 sec_level = authreq_to_seclevel(auth);
1782
1783 if (sec_level > conn->hcon->pending_sec_level)
1784 conn->hcon->pending_sec_level = sec_level;
1785
1786 /* If we need MITM check that it can be achieved */
1787 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1788 u8 method;
1789
1790 method = get_auth_method(smp, conn->hcon->io_capability,
1791 req->io_capability);
1792 if (method == JUST_WORKS || method == JUST_CFM)
1793 return SMP_AUTH_REQUIREMENTS;
1794 }
1795
1796 key_size = min(req->max_key_size, rsp.max_key_size);
1797 if (check_enc_key_size(conn, key_size))
1798 return SMP_ENC_KEY_SIZE;
1799
1800 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1801
1802 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1803 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1804
1805 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1806
1807 clear_bit(SMP_FLAG_INITIATOR, &smp->flags);
1808
1809 /* Strictly speaking we shouldn't allow Pairing Confirm for the
1810 * SC case, however some implementations incorrectly copy RFU auth
1811 * req bits from our security request, which may create a false
1812 * positive SC enablement.
1813 */
1814 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1815
1816 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1817 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
1818 /* Clear bits which are generated but not distributed */
1819 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1820 /* Wait for Public Key from Initiating Device */
1821 return 0;
1822 }
1823
1824 /* Request setup of TK */
1825 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability);
1826 if (ret)
1827 return SMP_UNSPECIFIED;
1828
1829 return 0;
1830}
1831
1832static u8 sc_send_public_key(struct smp_chan *smp)
1833{
1834 struct hci_dev *hdev = smp->conn->hcon->hdev;
1835
1836 BT_DBG("");
1837
1838 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) {
1839 struct l2cap_chan *chan = hdev->smp_data;
1840 struct smp_dev *smp_dev;
1841
1842 if (!chan || !chan->data)
1843 return SMP_UNSPECIFIED;
1844
1845 smp_dev = chan->data;
1846
1847 memcpy(smp->local_pk, smp_dev->local_pk, 64);
1848 memcpy(smp->local_sk, smp_dev->local_sk, 32);
1849 memcpy(smp->lr, smp_dev->local_rand, 16);
1850
1851 if (smp_dev->debug_key)
1852 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1853
1854 goto done;
1855 }
1856
1857 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
1858 BT_DBG("Using debug keys");
1859 memcpy(smp->local_pk, debug_pk, 64);
1860 memcpy(smp->local_sk, debug_sk, 32);
1861 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1862 } else {
1863 while (true) {
1864 /* Generate local key pair for Secure Connections */
1865 if (!ecc_make_key(smp->local_pk, smp->local_sk))
1866 return SMP_UNSPECIFIED;
1867
1868 /* This is unlikely, but we need to check that
1869 * we didn't accidentially generate a debug key.
1870 */
1871 if (memcmp(smp->local_sk, debug_sk, 32))
1872 break;
1873 }
1874 }
1875
1876done:
1877 SMP_DBG("Local Public Key X: %32phN", smp->local_pk);
1878 SMP_DBG("Local Public Key Y: %32phN", smp->local_pk + 32);
1879 SMP_DBG("Local Private Key: %32phN", smp->local_sk);
1880
1881 smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk);
1882
1883 return 0;
1884}
1885
1886static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
1887{
1888 struct smp_cmd_pairing *req, *rsp = (void *) skb->data;
1889 struct l2cap_chan *chan = conn->smp;
1890 struct smp_chan *smp = chan->data;
1891 struct hci_dev *hdev = conn->hcon->hdev;
1892 u8 key_size, auth;
1893 int ret;
1894
1895 BT_DBG("conn %p", conn);
1896
1897 if (skb->len < sizeof(*rsp))
1898 return SMP_INVALID_PARAMS;
1899
1900 if (conn->hcon->role != HCI_ROLE_MASTER)
1901 return SMP_CMD_NOTSUPP;
1902
1903 skb_pull(skb, sizeof(*rsp));
1904
1905 req = (void *) &smp->preq[1];
1906
1907 key_size = min(req->max_key_size, rsp->max_key_size);
1908 if (check_enc_key_size(conn, key_size))
1909 return SMP_ENC_KEY_SIZE;
1910
1911 auth = rsp->auth_req & AUTH_REQ_MASK(hdev);
1912
1913 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1914 return SMP_AUTH_REQUIREMENTS;
1915
1916 /* If the remote side's OOB flag is set it means it has
1917 * successfully received our local OOB data - therefore set the
1918 * flag to indicate that local OOB is in use.
1919 */
1920 if (rsp->oob_flag == SMP_OOB_PRESENT)
1921 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1922
1923 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1924 memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
1925
1926 /* Update remote key distribution in case the remote cleared
1927 * some bits that we had enabled in our request.
1928 */
1929 smp->remote_key_dist &= rsp->resp_key_dist;
1930
1931 /* For BR/EDR this means we're done and can start phase 3 */
1932 if (conn->hcon->type == ACL_LINK) {
1933 /* Clear bits which are generated but not distributed */
1934 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1935 smp_distribute_keys(smp);
1936 return 0;
1937 }
1938
1939 if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC))
1940 set_bit(SMP_FLAG_SC, &smp->flags);
1941 else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH)
1942 conn->hcon->pending_sec_level = BT_SECURITY_HIGH;
1943
1944 /* If we need MITM check that it can be achieved */
1945 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1946 u8 method;
1947
1948 method = get_auth_method(smp, req->io_capability,
1949 rsp->io_capability);
1950 if (method == JUST_WORKS || method == JUST_CFM)
1951 return SMP_AUTH_REQUIREMENTS;
1952 }
1953
1954 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1955
1956 /* Update remote key distribution in case the remote cleared
1957 * some bits that we had enabled in our request.
1958 */
1959 smp->remote_key_dist &= rsp->resp_key_dist;
1960
1961 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1962 /* Clear bits which are generated but not distributed */
1963 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1964 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
1965 return sc_send_public_key(smp);
1966 }
1967
1968 auth |= req->auth_req;
1969
1970 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability);
1971 if (ret)
1972 return SMP_UNSPECIFIED;
1973
1974 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
1975
1976 /* Can't compose response until we have been confirmed */
1977 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
1978 return smp_confirm(smp);
1979
1980 return 0;
1981}
1982
1983static u8 sc_check_confirm(struct smp_chan *smp)
1984{
1985 struct l2cap_conn *conn = smp->conn;
1986
1987 BT_DBG("");
1988
1989 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
1990 return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM);
1991
1992 if (conn->hcon->out) {
1993 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1994 smp->prnd);
1995 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1996 }
1997
1998 return 0;
1999}
2000
2001/* Work-around for some implementations that incorrectly copy RFU bits
2002 * from our security request and thereby create the impression that
2003 * we're doing SC when in fact the remote doesn't support it.
2004 */
2005static int fixup_sc_false_positive(struct smp_chan *smp)
2006{
2007 struct l2cap_conn *conn = smp->conn;
2008 struct hci_conn *hcon = conn->hcon;
2009 struct hci_dev *hdev = hcon->hdev;
2010 struct smp_cmd_pairing *req, *rsp;
2011 u8 auth;
2012
2013 /* The issue is only observed when we're in slave role */
2014 if (hcon->out)
2015 return SMP_UNSPECIFIED;
2016
2017 if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) {
2018 BT_ERR("Refusing SMP SC -> legacy fallback in SC-only mode");
2019 return SMP_UNSPECIFIED;
2020 }
2021
2022 BT_ERR("Trying to fall back to legacy SMP");
2023
2024 req = (void *) &smp->preq[1];
2025 rsp = (void *) &smp->prsp[1];
2026
2027 /* Rebuild key dist flags which may have been cleared for SC */
2028 smp->remote_key_dist = (req->init_key_dist & rsp->resp_key_dist);
2029
2030 auth = req->auth_req & AUTH_REQ_MASK(hdev);
2031
2032 if (tk_request(conn, 0, auth, rsp->io_capability, req->io_capability)) {
2033 BT_ERR("Failed to fall back to legacy SMP");
2034 return SMP_UNSPECIFIED;
2035 }
2036
2037 clear_bit(SMP_FLAG_SC, &smp->flags);
2038
2039 return 0;
2040}
2041
2042static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
2043{
2044 struct l2cap_chan *chan = conn->smp;
2045 struct smp_chan *smp = chan->data;
2046
2047 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
2048
2049 if (skb->len < sizeof(smp->pcnf))
2050 return SMP_INVALID_PARAMS;
2051
2052 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
2053 skb_pull(skb, sizeof(smp->pcnf));
2054
2055 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
2056 int ret;
2057
2058 /* Public Key exchange must happen before any other steps */
2059 if (test_bit(SMP_FLAG_REMOTE_PK, &smp->flags))
2060 return sc_check_confirm(smp);
2061
2062 BT_ERR("Unexpected SMP Pairing Confirm");
2063
2064 ret = fixup_sc_false_positive(smp);
2065 if (ret)
2066 return ret;
2067 }
2068
2069 if (conn->hcon->out) {
2070 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2071 smp->prnd);
2072 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2073 return 0;
2074 }
2075
2076 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
2077 return smp_confirm(smp);
2078
2079 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
2080
2081 return 0;
2082}
2083
2084static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
2085{
2086 struct l2cap_chan *chan = conn->smp;
2087 struct smp_chan *smp = chan->data;
2088 struct hci_conn *hcon = conn->hcon;
2089 u8 *pkax, *pkbx, *na, *nb;
2090 u32 passkey;
2091 int err;
2092
2093 BT_DBG("conn %p", conn);
2094
2095 if (skb->len < sizeof(smp->rrnd))
2096 return SMP_INVALID_PARAMS;
2097
2098 memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd));
2099 skb_pull(skb, sizeof(smp->rrnd));
2100
2101 if (!test_bit(SMP_FLAG_SC, &smp->flags))
2102 return smp_random(smp);
2103
2104 if (hcon->out) {
2105 pkax = smp->local_pk;
2106 pkbx = smp->remote_pk;
2107 na = smp->prnd;
2108 nb = smp->rrnd;
2109 } else {
2110 pkax = smp->remote_pk;
2111 pkbx = smp->local_pk;
2112 na = smp->rrnd;
2113 nb = smp->prnd;
2114 }
2115
2116 if (smp->method == REQ_OOB) {
2117 if (!hcon->out)
2118 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2119 sizeof(smp->prnd), smp->prnd);
2120 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2121 goto mackey_and_ltk;
2122 }
2123
2124 /* Passkey entry has special treatment */
2125 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2126 return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM);
2127
2128 if (hcon->out) {
2129 u8 cfm[16];
2130
2131 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
2132 smp->rrnd, 0, cfm);
2133 if (err)
2134 return SMP_UNSPECIFIED;
2135
2136 if (memcmp(smp->pcnf, cfm, 16))
2137 return SMP_CONFIRM_FAILED;
2138 } else {
2139 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2140 smp->prnd);
2141 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2142 }
2143
2144mackey_and_ltk:
2145 /* Generate MacKey and LTK */
2146 err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk);
2147 if (err)
2148 return SMP_UNSPECIFIED;
2149
2150 if (smp->method == JUST_WORKS || smp->method == REQ_OOB) {
2151 if (hcon->out) {
2152 sc_dhkey_check(smp);
2153 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2154 }
2155 return 0;
2156 }
2157
2158 err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);
2159 if (err)
2160 return SMP_UNSPECIFIED;
2161
2162 err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type,
2163 hcon->dst_type, passkey, 0);
2164 if (err)
2165 return SMP_UNSPECIFIED;
2166
2167 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2168
2169 return 0;
2170}
2171
2172static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
2173{
2174 struct smp_ltk *key;
2175 struct hci_conn *hcon = conn->hcon;
2176
2177 key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role);
2178 if (!key)
2179 return false;
2180
2181 if (smp_ltk_sec_level(key) < sec_level)
2182 return false;
2183
2184 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
2185 return true;
2186
2187 hci_le_start_enc(hcon, key->ediv, key->rand, key->val, key->enc_size);
2188 hcon->enc_key_size = key->enc_size;
2189
2190 /* We never store STKs for master role, so clear this flag */
2191 clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
2192
2193 return true;
2194}
2195
2196bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level,
2197 enum smp_key_pref key_pref)
2198{
2199 if (sec_level == BT_SECURITY_LOW)
2200 return true;
2201
2202 /* If we're encrypted with an STK but the caller prefers using
2203 * LTK claim insufficient security. This way we allow the
2204 * connection to be re-encrypted with an LTK, even if the LTK
2205 * provides the same level of security. Only exception is if we
2206 * don't have an LTK (e.g. because of key distribution bits).
2207 */
2208 if (key_pref == SMP_USE_LTK &&
2209 test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) &&
2210 hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role))
2211 return false;
2212
2213 if (hcon->sec_level >= sec_level)
2214 return true;
2215
2216 return false;
2217}
2218
2219static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
2220{
2221 struct smp_cmd_security_req *rp = (void *) skb->data;
2222 struct smp_cmd_pairing cp;
2223 struct hci_conn *hcon = conn->hcon;
2224 struct hci_dev *hdev = hcon->hdev;
2225 struct smp_chan *smp;
2226 u8 sec_level, auth;
2227
2228 BT_DBG("conn %p", conn);
2229
2230 if (skb->len < sizeof(*rp))
2231 return SMP_INVALID_PARAMS;
2232
2233 if (hcon->role != HCI_ROLE_MASTER)
2234 return SMP_CMD_NOTSUPP;
2235
2236 auth = rp->auth_req & AUTH_REQ_MASK(hdev);
2237
2238 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
2239 return SMP_AUTH_REQUIREMENTS;
2240
2241 if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
2242 sec_level = BT_SECURITY_MEDIUM;
2243 else
2244 sec_level = authreq_to_seclevel(auth);
2245
2246 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
2247 return 0;
2248
2249 if (sec_level > hcon->pending_sec_level)
2250 hcon->pending_sec_level = sec_level;
2251
2252 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2253 return 0;
2254
2255 smp = smp_chan_create(conn);
2256 if (!smp)
2257 return SMP_UNSPECIFIED;
2258
2259 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
2260 (auth & SMP_AUTH_BONDING))
2261 return SMP_PAIRING_NOTSUPP;
2262
2263 skb_pull(skb, sizeof(*rp));
2264
2265 memset(&cp, 0, sizeof(cp));
2266 build_pairing_cmd(conn, &cp, NULL, auth);
2267
2268 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2269 memcpy(&smp->preq[1], &cp, sizeof(cp));
2270
2271 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2272 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2273
2274 return 0;
2275}
2276
2277int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
2278{
2279 struct l2cap_conn *conn = hcon->l2cap_data;
2280 struct l2cap_chan *chan;
2281 struct smp_chan *smp;
2282 __u8 authreq;
2283 int ret;
2284
2285 BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);
2286
2287 /* This may be NULL if there's an unexpected disconnection */
2288 if (!conn)
2289 return 1;
2290
2291 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED))
2292 return 1;
2293
2294 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
2295 return 1;
2296
2297 if (sec_level > hcon->pending_sec_level)
2298 hcon->pending_sec_level = sec_level;
2299
2300 if (hcon->role == HCI_ROLE_MASTER)
2301 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2302 return 0;
2303
2304 chan = conn->smp;
2305 if (!chan) {
2306 BT_ERR("SMP security requested but not available");
2307 return 1;
2308 }
2309
2310 l2cap_chan_lock(chan);
2311
2312 /* If SMP is already in progress ignore this request */
2313 if (chan->data) {
2314 ret = 0;
2315 goto unlock;
2316 }
2317
2318 smp = smp_chan_create(conn);
2319 if (!smp) {
2320 ret = 1;
2321 goto unlock;
2322 }
2323
2324 authreq = seclevel_to_authreq(sec_level);
2325
2326 if (hci_dev_test_flag(hcon->hdev, HCI_SC_ENABLED))
2327 authreq |= SMP_AUTH_SC;
2328
2329 /* Require MITM if IO Capability allows or the security level
2330 * requires it.
2331 */
2332 if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT ||
2333 hcon->pending_sec_level > BT_SECURITY_MEDIUM)
2334 authreq |= SMP_AUTH_MITM;
2335
2336 if (hcon->role == HCI_ROLE_MASTER) {
2337 struct smp_cmd_pairing cp;
2338
2339 build_pairing_cmd(conn, &cp, NULL, authreq);
2340 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2341 memcpy(&smp->preq[1], &cp, sizeof(cp));
2342
2343 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2344 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2345 } else {
2346 struct smp_cmd_security_req cp;
2347 cp.auth_req = authreq;
2348 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
2349 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ);
2350 }
2351
2352 set_bit(SMP_FLAG_INITIATOR, &smp->flags);
2353 ret = 0;
2354
2355unlock:
2356 l2cap_chan_unlock(chan);
2357 return ret;
2358}
2359
2360void smp_cancel_pairing(struct hci_conn *hcon)
2361{
2362 struct l2cap_conn *conn = hcon->l2cap_data;
2363 struct l2cap_chan *chan;
2364 struct smp_chan *smp;
2365
2366 if (!conn)
2367 return;
2368
2369 chan = conn->smp;
2370 if (!chan)
2371 return;
2372
2373 l2cap_chan_lock(chan);
2374
2375 smp = chan->data;
2376 if (smp) {
2377 if (test_bit(SMP_FLAG_COMPLETE, &smp->flags))
2378 smp_failure(conn, 0);
2379 else
2380 smp_failure(conn, SMP_UNSPECIFIED);
2381 }
2382
2383 l2cap_chan_unlock(chan);
2384}
2385
2386static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb)
2387{
2388 struct smp_cmd_encrypt_info *rp = (void *) skb->data;
2389 struct l2cap_chan *chan = conn->smp;
2390 struct smp_chan *smp = chan->data;
2391
2392 BT_DBG("conn %p", conn);
2393
2394 if (skb->len < sizeof(*rp))
2395 return SMP_INVALID_PARAMS;
2396
2397 SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT);
2398
2399 skb_pull(skb, sizeof(*rp));
2400
2401 memcpy(smp->tk, rp->ltk, sizeof(smp->tk));
2402
2403 return 0;
2404}
2405
2406static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
2407{
2408 struct smp_cmd_master_ident *rp = (void *) skb->data;
2409 struct l2cap_chan *chan = conn->smp;
2410 struct smp_chan *smp = chan->data;
2411 struct hci_dev *hdev = conn->hcon->hdev;
2412 struct hci_conn *hcon = conn->hcon;
2413 struct smp_ltk *ltk;
2414 u8 authenticated;
2415
2416 BT_DBG("conn %p", conn);
2417
2418 if (skb->len < sizeof(*rp))
2419 return SMP_INVALID_PARAMS;
2420
2421 /* Mark the information as received */
2422 smp->remote_key_dist &= ~SMP_DIST_ENC_KEY;
2423
2424 if (smp->remote_key_dist & SMP_DIST_ID_KEY)
2425 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
2426 else if (smp->remote_key_dist & SMP_DIST_SIGN)
2427 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2428
2429 skb_pull(skb, sizeof(*rp));
2430
2431 authenticated = (hcon->sec_level == BT_SECURITY_HIGH);
2432 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK,
2433 authenticated, smp->tk, smp->enc_key_size,
2434 rp->ediv, rp->rand);
2435 smp->ltk = ltk;
2436 if (!(smp->remote_key_dist & KEY_DIST_MASK))
2437 smp_distribute_keys(smp);
2438
2439 return 0;
2440}
2441
2442static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb)
2443{
2444 struct smp_cmd_ident_info *info = (void *) skb->data;
2445 struct l2cap_chan *chan = conn->smp;
2446 struct smp_chan *smp = chan->data;
2447
2448 BT_DBG("");
2449
2450 if (skb->len < sizeof(*info))
2451 return SMP_INVALID_PARAMS;
2452
2453 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO);
2454
2455 skb_pull(skb, sizeof(*info));
2456
2457 memcpy(smp->irk, info->irk, 16);
2458
2459 return 0;
2460}
2461
2462static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,
2463 struct sk_buff *skb)
2464{
2465 struct smp_cmd_ident_addr_info *info = (void *) skb->data;
2466 struct l2cap_chan *chan = conn->smp;
2467 struct smp_chan *smp = chan->data;
2468 struct hci_conn *hcon = conn->hcon;
2469 bdaddr_t rpa;
2470
2471 BT_DBG("");
2472
2473 if (skb->len < sizeof(*info))
2474 return SMP_INVALID_PARAMS;
2475
2476 /* Mark the information as received */
2477 smp->remote_key_dist &= ~SMP_DIST_ID_KEY;
2478
2479 if (smp->remote_key_dist & SMP_DIST_SIGN)
2480 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2481
2482 skb_pull(skb, sizeof(*info));
2483
2484 /* Strictly speaking the Core Specification (4.1) allows sending
2485 * an empty address which would force us to rely on just the IRK
2486 * as "identity information". However, since such
2487 * implementations are not known of and in order to not over
2488 * complicate our implementation, simply pretend that we never
2489 * received an IRK for such a device.
2490 *
2491 * The Identity Address must also be a Static Random or Public
2492 * Address, which hci_is_identity_address() checks for.
2493 */
2494 if (!bacmp(&info->bdaddr, BDADDR_ANY) ||
2495 !hci_is_identity_address(&info->bdaddr, info->addr_type)) {
2496 BT_ERR("Ignoring IRK with no identity address");
2497 goto distribute;
2498 }
2499
2500 bacpy(&smp->id_addr, &info->bdaddr);
2501 smp->id_addr_type = info->addr_type;
2502
2503 if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type))
2504 bacpy(&rpa, &hcon->dst);
2505 else
2506 bacpy(&rpa, BDADDR_ANY);
2507
2508 smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr,
2509 smp->id_addr_type, smp->irk, &rpa);
2510
2511distribute:
2512 if (!(smp->remote_key_dist & KEY_DIST_MASK))
2513 smp_distribute_keys(smp);
2514
2515 return 0;
2516}
2517
2518static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb)
2519{
2520 struct smp_cmd_sign_info *rp = (void *) skb->data;
2521 struct l2cap_chan *chan = conn->smp;
2522 struct smp_chan *smp = chan->data;
2523 struct smp_csrk *csrk;
2524
2525 BT_DBG("conn %p", conn);
2526
2527 if (skb->len < sizeof(*rp))
2528 return SMP_INVALID_PARAMS;
2529
2530 /* Mark the information as received */
2531 smp->remote_key_dist &= ~SMP_DIST_SIGN;
2532
2533 skb_pull(skb, sizeof(*rp));
2534
2535 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
2536 if (csrk) {
2537 if (conn->hcon->sec_level > BT_SECURITY_MEDIUM)
2538 csrk->type = MGMT_CSRK_REMOTE_AUTHENTICATED;
2539 else
2540 csrk->type = MGMT_CSRK_REMOTE_UNAUTHENTICATED;
2541 memcpy(csrk->val, rp->csrk, sizeof(csrk->val));
2542 }
2543 smp->csrk = csrk;
2544 smp_distribute_keys(smp);
2545
2546 return 0;
2547}
2548
2549static u8 sc_select_method(struct smp_chan *smp)
2550{
2551 struct l2cap_conn *conn = smp->conn;
2552 struct hci_conn *hcon = conn->hcon;
2553 struct smp_cmd_pairing *local, *remote;
2554 u8 local_mitm, remote_mitm, local_io, remote_io, method;
2555
2556 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags) ||
2557 test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags))
2558 return REQ_OOB;
2559
2560 /* The preq/prsp contain the raw Pairing Request/Response PDUs
2561 * which are needed as inputs to some crypto functions. To get
2562 * the "struct smp_cmd_pairing" from them we need to skip the
2563 * first byte which contains the opcode.
2564 */
2565 if (hcon->out) {
2566 local = (void *) &smp->preq[1];
2567 remote = (void *) &smp->prsp[1];
2568 } else {
2569 local = (void *) &smp->prsp[1];
2570 remote = (void *) &smp->preq[1];
2571 }
2572
2573 local_io = local->io_capability;
2574 remote_io = remote->io_capability;
2575
2576 local_mitm = (local->auth_req & SMP_AUTH_MITM);
2577 remote_mitm = (remote->auth_req & SMP_AUTH_MITM);
2578
2579 /* If either side wants MITM, look up the method from the table,
2580 * otherwise use JUST WORKS.
2581 */
2582 if (local_mitm || remote_mitm)
2583 method = get_auth_method(smp, local_io, remote_io);
2584 else
2585 method = JUST_WORKS;
2586
2587 /* Don't confirm locally initiated pairing attempts */
2588 if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags))
2589 method = JUST_WORKS;
2590
2591 return method;
2592}
2593
2594static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb)
2595{
2596 struct smp_cmd_public_key *key = (void *) skb->data;
2597 struct hci_conn *hcon = conn->hcon;
2598 struct l2cap_chan *chan = conn->smp;
2599 struct smp_chan *smp = chan->data;
2600 struct hci_dev *hdev = hcon->hdev;
2601 struct smp_cmd_pairing_confirm cfm;
2602 int err;
2603
2604 BT_DBG("conn %p", conn);
2605
2606 if (skb->len < sizeof(*key))
2607 return SMP_INVALID_PARAMS;
2608
2609 memcpy(smp->remote_pk, key, 64);
2610
2611 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags)) {
2612 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk,
2613 smp->rr, 0, cfm.confirm_val);
2614 if (err)
2615 return SMP_UNSPECIFIED;
2616
2617 if (memcmp(cfm.confirm_val, smp->pcnf, 16))
2618 return SMP_CONFIRM_FAILED;
2619 }
2620
2621 /* Non-initiating device sends its public key after receiving
2622 * the key from the initiating device.
2623 */
2624 if (!hcon->out) {
2625 err = sc_send_public_key(smp);
2626 if (err)
2627 return err;
2628 }
2629
2630 SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk);
2631 SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32);
2632
2633 if (!ecdh_shared_secret(smp->remote_pk, smp->local_sk, smp->dhkey))
2634 return SMP_UNSPECIFIED;
2635
2636 SMP_DBG("DHKey %32phN", smp->dhkey);
2637
2638 set_bit(SMP_FLAG_REMOTE_PK, &smp->flags);
2639
2640 smp->method = sc_select_method(smp);
2641
2642 BT_DBG("%s selected method 0x%02x", hdev->name, smp->method);
2643
2644 /* JUST_WORKS and JUST_CFM result in an unauthenticated key */
2645 if (smp->method == JUST_WORKS || smp->method == JUST_CFM)
2646 hcon->pending_sec_level = BT_SECURITY_MEDIUM;
2647 else
2648 hcon->pending_sec_level = BT_SECURITY_FIPS;
2649
2650 if (!memcmp(debug_pk, smp->remote_pk, 64))
2651 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
2652
2653 if (smp->method == DSP_PASSKEY) {
2654 get_random_bytes(&hcon->passkey_notify,
2655 sizeof(hcon->passkey_notify));
2656 hcon->passkey_notify %= 1000000;
2657 hcon->passkey_entered = 0;
2658 smp->passkey_round = 0;
2659 if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type,
2660 hcon->dst_type,
2661 hcon->passkey_notify,
2662 hcon->passkey_entered))
2663 return SMP_UNSPECIFIED;
2664 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2665 return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY);
2666 }
2667
2668 if (smp->method == REQ_OOB) {
2669 if (hcon->out)
2670 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2671 sizeof(smp->prnd), smp->prnd);
2672
2673 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2674
2675 return 0;
2676 }
2677
2678 if (hcon->out)
2679 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2680
2681 if (smp->method == REQ_PASSKEY) {
2682 if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type,
2683 hcon->dst_type))
2684 return SMP_UNSPECIFIED;
2685 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2686 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2687 return 0;
2688 }
2689
2690 /* The Initiating device waits for the non-initiating device to
2691 * send the confirm value.
2692 */
2693 if (conn->hcon->out)
2694 return 0;
2695
2696 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd,
2697 0, cfm.confirm_val);
2698 if (err)
2699 return SMP_UNSPECIFIED;
2700
2701 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
2702 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2703
2704 return 0;
2705}
2706
2707static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb)
2708{
2709 struct smp_cmd_dhkey_check *check = (void *) skb->data;
2710 struct l2cap_chan *chan = conn->smp;
2711 struct hci_conn *hcon = conn->hcon;
2712 struct smp_chan *smp = chan->data;
2713 u8 a[7], b[7], *local_addr, *remote_addr;
2714 u8 io_cap[3], r[16], e[16];
2715 int err;
2716
2717 BT_DBG("conn %p", conn);
2718
2719 if (skb->len < sizeof(*check))
2720 return SMP_INVALID_PARAMS;
2721
2722 memcpy(a, &hcon->init_addr, 6);
2723 memcpy(b, &hcon->resp_addr, 6);
2724 a[6] = hcon->init_addr_type;
2725 b[6] = hcon->resp_addr_type;
2726
2727 if (hcon->out) {
2728 local_addr = a;
2729 remote_addr = b;
2730 memcpy(io_cap, &smp->prsp[1], 3);
2731 } else {
2732 local_addr = b;
2733 remote_addr = a;
2734 memcpy(io_cap, &smp->preq[1], 3);
2735 }
2736
2737 memset(r, 0, sizeof(r));
2738
2739 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2740 put_unaligned_le32(hcon->passkey_notify, r);
2741 else if (smp->method == REQ_OOB)
2742 memcpy(r, smp->lr, 16);
2743
2744 err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r,
2745 io_cap, remote_addr, local_addr, e);
2746 if (err)
2747 return SMP_UNSPECIFIED;
2748
2749 if (memcmp(check->e, e, 16))
2750 return SMP_DHKEY_CHECK_FAILED;
2751
2752 if (!hcon->out) {
2753 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
2754 set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags);
2755 return 0;
2756 }
2757
2758 /* Slave sends DHKey check as response to master */
2759 sc_dhkey_check(smp);
2760 }
2761
2762 sc_add_ltk(smp);
2763
2764 if (hcon->out) {
2765 hci_le_start_enc(hcon, 0, 0, smp->tk, smp->enc_key_size);
2766 hcon->enc_key_size = smp->enc_key_size;
2767 }
2768
2769 return 0;
2770}
2771
2772static int smp_cmd_keypress_notify(struct l2cap_conn *conn,
2773 struct sk_buff *skb)
2774{
2775 struct smp_cmd_keypress_notify *kp = (void *) skb->data;
2776
2777 BT_DBG("value 0x%02x", kp->value);
2778
2779 return 0;
2780}
2781
2782static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb)
2783{
2784 struct l2cap_conn *conn = chan->conn;
2785 struct hci_conn *hcon = conn->hcon;
2786 struct smp_chan *smp;
2787 __u8 code, reason;
2788 int err = 0;
2789
2790 if (skb->len < 1)
2791 return -EILSEQ;
2792
2793 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) {
2794 reason = SMP_PAIRING_NOTSUPP;
2795 goto done;
2796 }
2797
2798 code = skb->data[0];
2799 skb_pull(skb, sizeof(code));
2800
2801 smp = chan->data;
2802
2803 if (code > SMP_CMD_MAX)
2804 goto drop;
2805
2806 if (smp && !test_and_clear_bit(code, &smp->allow_cmd))
2807 goto drop;
2808
2809 /* If we don't have a context the only allowed commands are
2810 * pairing request and security request.
2811 */
2812 if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ)
2813 goto drop;
2814
2815 switch (code) {
2816 case SMP_CMD_PAIRING_REQ:
2817 reason = smp_cmd_pairing_req(conn, skb);
2818 break;
2819
2820 case SMP_CMD_PAIRING_FAIL:
2821 smp_failure(conn, 0);
2822 err = -EPERM;
2823 break;
2824
2825 case SMP_CMD_PAIRING_RSP:
2826 reason = smp_cmd_pairing_rsp(conn, skb);
2827 break;
2828
2829 case SMP_CMD_SECURITY_REQ:
2830 reason = smp_cmd_security_req(conn, skb);
2831 break;
2832
2833 case SMP_CMD_PAIRING_CONFIRM:
2834 reason = smp_cmd_pairing_confirm(conn, skb);
2835 break;
2836
2837 case SMP_CMD_PAIRING_RANDOM:
2838 reason = smp_cmd_pairing_random(conn, skb);
2839 break;
2840
2841 case SMP_CMD_ENCRYPT_INFO:
2842 reason = smp_cmd_encrypt_info(conn, skb);
2843 break;
2844
2845 case SMP_CMD_MASTER_IDENT:
2846 reason = smp_cmd_master_ident(conn, skb);
2847 break;
2848
2849 case SMP_CMD_IDENT_INFO:
2850 reason = smp_cmd_ident_info(conn, skb);
2851 break;
2852
2853 case SMP_CMD_IDENT_ADDR_INFO:
2854 reason = smp_cmd_ident_addr_info(conn, skb);
2855 break;
2856
2857 case SMP_CMD_SIGN_INFO:
2858 reason = smp_cmd_sign_info(conn, skb);
2859 break;
2860
2861 case SMP_CMD_PUBLIC_KEY:
2862 reason = smp_cmd_public_key(conn, skb);
2863 break;
2864
2865 case SMP_CMD_DHKEY_CHECK:
2866 reason = smp_cmd_dhkey_check(conn, skb);
2867 break;
2868
2869 case SMP_CMD_KEYPRESS_NOTIFY:
2870 reason = smp_cmd_keypress_notify(conn, skb);
2871 break;
2872
2873 default:
2874 BT_DBG("Unknown command code 0x%2.2x", code);
2875 reason = SMP_CMD_NOTSUPP;
2876 goto done;
2877 }
2878
2879done:
2880 if (!err) {
2881 if (reason)
2882 smp_failure(conn, reason);
2883 kfree_skb(skb);
2884 }
2885
2886 return err;
2887
2888drop:
2889 BT_ERR("%s unexpected SMP command 0x%02x from %pMR", hcon->hdev->name,
2890 code, &hcon->dst);
2891 kfree_skb(skb);
2892 return 0;
2893}
2894
2895static void smp_teardown_cb(struct l2cap_chan *chan, int err)
2896{
2897 struct l2cap_conn *conn = chan->conn;
2898
2899 BT_DBG("chan %p", chan);
2900
2901 if (chan->data)
2902 smp_chan_destroy(conn);
2903
2904 conn->smp = NULL;
2905 l2cap_chan_put(chan);
2906}
2907
2908static void bredr_pairing(struct l2cap_chan *chan)
2909{
2910 struct l2cap_conn *conn = chan->conn;
2911 struct hci_conn *hcon = conn->hcon;
2912 struct hci_dev *hdev = hcon->hdev;
2913 struct smp_cmd_pairing req;
2914 struct smp_chan *smp;
2915
2916 BT_DBG("chan %p", chan);
2917
2918 /* Only new pairings are interesting */
2919 if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags))
2920 return;
2921
2922 /* Don't bother if we're not encrypted */
2923 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
2924 return;
2925
2926 /* Only master may initiate SMP over BR/EDR */
2927 if (hcon->role != HCI_ROLE_MASTER)
2928 return;
2929
2930 /* Secure Connections support must be enabled */
2931 if (!hci_dev_test_flag(hdev, HCI_SC_ENABLED))
2932 return;
2933
2934 /* BR/EDR must use Secure Connections for SMP */
2935 if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) &&
2936 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
2937 return;
2938
2939 /* If our LE support is not enabled don't do anything */
2940 if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED))
2941 return;
2942
2943 /* Don't bother if remote LE support is not enabled */
2944 if (!lmp_host_le_capable(hcon))
2945 return;
2946
2947 /* Remote must support SMP fixed chan for BR/EDR */
2948 if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR))
2949 return;
2950
2951 /* Don't bother if SMP is already ongoing */
2952 if (chan->data)
2953 return;
2954
2955 smp = smp_chan_create(conn);
2956 if (!smp) {
2957 BT_ERR("%s unable to create SMP context for BR/EDR",
2958 hdev->name);
2959 return;
2960 }
2961
2962 set_bit(SMP_FLAG_SC, &smp->flags);
2963
2964 BT_DBG("%s starting SMP over BR/EDR", hdev->name);
2965
2966 /* Prepare and send the BR/EDR SMP Pairing Request */
2967 build_bredr_pairing_cmd(smp, &req, NULL);
2968
2969 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2970 memcpy(&smp->preq[1], &req, sizeof(req));
2971
2972 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req);
2973 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2974}
2975
2976static void smp_resume_cb(struct l2cap_chan *chan)
2977{
2978 struct smp_chan *smp = chan->data;
2979 struct l2cap_conn *conn = chan->conn;
2980 struct hci_conn *hcon = conn->hcon;
2981
2982 BT_DBG("chan %p", chan);
2983
2984 if (hcon->type == ACL_LINK) {
2985 bredr_pairing(chan);
2986 return;
2987 }
2988
2989 if (!smp)
2990 return;
2991
2992 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
2993 return;
2994
2995 cancel_delayed_work(&smp->security_timer);
2996
2997 smp_distribute_keys(smp);
2998}
2999
3000static void smp_ready_cb(struct l2cap_chan *chan)
3001{
3002 struct l2cap_conn *conn = chan->conn;
3003 struct hci_conn *hcon = conn->hcon;
3004
3005 BT_DBG("chan %p", chan);
3006
3007 /* No need to call l2cap_chan_hold() here since we already own
3008 * the reference taken in smp_new_conn_cb(). This is just the
3009 * first time that we tie it to a specific pointer. The code in
3010 * l2cap_core.c ensures that there's no risk this function wont
3011 * get called if smp_new_conn_cb was previously called.
3012 */
3013 conn->smp = chan;
3014
3015 if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
3016 bredr_pairing(chan);
3017}
3018
3019static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
3020{
3021 int err;
3022
3023 BT_DBG("chan %p", chan);
3024
3025 err = smp_sig_channel(chan, skb);
3026 if (err) {
3027 struct smp_chan *smp = chan->data;
3028
3029 if (smp)
3030 cancel_delayed_work_sync(&smp->security_timer);
3031
3032 hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE);
3033 }
3034
3035 return err;
3036}
3037
3038static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan,
3039 unsigned long hdr_len,
3040 unsigned long len, int nb)
3041{
3042 struct sk_buff *skb;
3043
3044 skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL);
3045 if (!skb)
3046 return ERR_PTR(-ENOMEM);
3047
3048 skb->priority = HCI_PRIO_MAX;
3049 bt_cb(skb)->l2cap.chan = chan;
3050
3051 return skb;
3052}
3053
3054static const struct l2cap_ops smp_chan_ops = {
3055 .name = "Security Manager",
3056 .ready = smp_ready_cb,
3057 .recv = smp_recv_cb,
3058 .alloc_skb = smp_alloc_skb_cb,
3059 .teardown = smp_teardown_cb,
3060 .resume = smp_resume_cb,
3061
3062 .new_connection = l2cap_chan_no_new_connection,
3063 .state_change = l2cap_chan_no_state_change,
3064 .close = l2cap_chan_no_close,
3065 .defer = l2cap_chan_no_defer,
3066 .suspend = l2cap_chan_no_suspend,
3067 .set_shutdown = l2cap_chan_no_set_shutdown,
3068 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
3069};
3070
3071static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan)
3072{
3073 struct l2cap_chan *chan;
3074
3075 BT_DBG("pchan %p", pchan);
3076
3077 chan = l2cap_chan_create();
3078 if (!chan)
3079 return NULL;
3080
3081 chan->chan_type = pchan->chan_type;
3082 chan->ops = &smp_chan_ops;
3083 chan->scid = pchan->scid;
3084 chan->dcid = chan->scid;
3085 chan->imtu = pchan->imtu;
3086 chan->omtu = pchan->omtu;
3087 chan->mode = pchan->mode;
3088
3089 /* Other L2CAP channels may request SMP routines in order to
3090 * change the security level. This means that the SMP channel
3091 * lock must be considered in its own category to avoid lockdep
3092 * warnings.
3093 */
3094 atomic_set(&chan->nesting, L2CAP_NESTING_SMP);
3095
3096 BT_DBG("created chan %p", chan);
3097
3098 return chan;
3099}
3100
3101static const struct l2cap_ops smp_root_chan_ops = {
3102 .name = "Security Manager Root",
3103 .new_connection = smp_new_conn_cb,
3104
3105 /* None of these are implemented for the root channel */
3106 .close = l2cap_chan_no_close,
3107 .alloc_skb = l2cap_chan_no_alloc_skb,
3108 .recv = l2cap_chan_no_recv,
3109 .state_change = l2cap_chan_no_state_change,
3110 .teardown = l2cap_chan_no_teardown,
3111 .ready = l2cap_chan_no_ready,
3112 .defer = l2cap_chan_no_defer,
3113 .suspend = l2cap_chan_no_suspend,
3114 .resume = l2cap_chan_no_resume,
3115 .set_shutdown = l2cap_chan_no_set_shutdown,
3116 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
3117};
3118
3119static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid)
3120{
3121 struct l2cap_chan *chan;
3122 struct smp_dev *smp;
3123 struct crypto_skcipher *tfm_aes;
3124 struct crypto_shash *tfm_cmac;
3125
3126 if (cid == L2CAP_CID_SMP_BREDR) {
3127 smp = NULL;
3128 goto create_chan;
3129 }
3130
3131 smp = kzalloc(sizeof(*smp), GFP_KERNEL);
3132 if (!smp)
3133 return ERR_PTR(-ENOMEM);
3134
3135 tfm_aes = crypto_alloc_skcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
3136 if (IS_ERR(tfm_aes)) {
3137 BT_ERR("Unable to create ECB crypto context");
3138 kzfree(smp);
3139 return ERR_CAST(tfm_aes);
3140 }
3141
3142 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
3143 if (IS_ERR(tfm_cmac)) {
3144 BT_ERR("Unable to create CMAC crypto context");
3145 crypto_free_skcipher(tfm_aes);
3146 kzfree(smp);
3147 return ERR_CAST(tfm_cmac);
3148 }
3149
3150 smp->tfm_aes = tfm_aes;
3151 smp->tfm_cmac = tfm_cmac;
3152 smp->min_key_size = SMP_MIN_ENC_KEY_SIZE;
3153 smp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
3154
3155create_chan:
3156 chan = l2cap_chan_create();
3157 if (!chan) {
3158 if (smp) {
3159 crypto_free_skcipher(smp->tfm_aes);
3160 crypto_free_shash(smp->tfm_cmac);
3161 kzfree(smp);
3162 }
3163 return ERR_PTR(-ENOMEM);
3164 }
3165
3166 chan->data = smp;
3167
3168 l2cap_add_scid(chan, cid);
3169
3170 l2cap_chan_set_defaults(chan);
3171
3172 if (cid == L2CAP_CID_SMP) {
3173 u8 bdaddr_type;
3174
3175 hci_copy_identity_address(hdev, &chan->src, &bdaddr_type);
3176
3177 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
3178 chan->src_type = BDADDR_LE_PUBLIC;
3179 else
3180 chan->src_type = BDADDR_LE_RANDOM;
3181 } else {
3182 bacpy(&chan->src, &hdev->bdaddr);
3183 chan->src_type = BDADDR_BREDR;
3184 }
3185
3186 chan->state = BT_LISTEN;
3187 chan->mode = L2CAP_MODE_BASIC;
3188 chan->imtu = L2CAP_DEFAULT_MTU;
3189 chan->ops = &smp_root_chan_ops;
3190
3191 /* Set correct nesting level for a parent/listening channel */
3192 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
3193
3194 return chan;
3195}
3196
3197static void smp_del_chan(struct l2cap_chan *chan)
3198{
3199 struct smp_dev *smp;
3200
3201 BT_DBG("chan %p", chan);
3202
3203 smp = chan->data;
3204 if (smp) {
3205 chan->data = NULL;
3206 crypto_free_skcipher(smp->tfm_aes);
3207 crypto_free_shash(smp->tfm_cmac);
3208 kzfree(smp);
3209 }
3210
3211 l2cap_chan_put(chan);
3212}
3213
3214static ssize_t force_bredr_smp_read(struct file *file,
3215 char __user *user_buf,
3216 size_t count, loff_t *ppos)
3217{
3218 struct hci_dev *hdev = file->private_data;
3219 char buf[3];
3220
3221 buf[0] = hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP) ? 'Y': 'N';
3222 buf[1] = '\n';
3223 buf[2] = '\0';
3224 return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
3225}
3226
3227static ssize_t force_bredr_smp_write(struct file *file,
3228 const char __user *user_buf,
3229 size_t count, loff_t *ppos)
3230{
3231 struct hci_dev *hdev = file->private_data;
3232 char buf[32];
3233 size_t buf_size = min(count, (sizeof(buf)-1));
3234 bool enable;
3235
3236 if (copy_from_user(buf, user_buf, buf_size))
3237 return -EFAULT;
3238
3239 buf[buf_size] = '\0';
3240 if (strtobool(buf, &enable))
3241 return -EINVAL;
3242
3243 if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3244 return -EALREADY;
3245
3246 if (enable) {
3247 struct l2cap_chan *chan;
3248
3249 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3250 if (IS_ERR(chan))
3251 return PTR_ERR(chan);
3252
3253 hdev->smp_bredr_data = chan;
3254 } else {
3255 struct l2cap_chan *chan;
3256
3257 chan = hdev->smp_bredr_data;
3258 hdev->smp_bredr_data = NULL;
3259 smp_del_chan(chan);
3260 }
3261
3262 hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP);
3263
3264 return count;
3265}
3266
3267static const struct file_operations force_bredr_smp_fops = {
3268 .open = simple_open,
3269 .read = force_bredr_smp_read,
3270 .write = force_bredr_smp_write,
3271 .llseek = default_llseek,
3272};
3273
3274static ssize_t le_min_key_size_read(struct file *file,
3275 char __user *user_buf,
3276 size_t count, loff_t *ppos)
3277{
3278 struct hci_dev *hdev = file->private_data;
3279 char buf[4];
3280
3281 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->min_key_size);
3282
3283 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf));
3284}
3285
3286static ssize_t le_min_key_size_write(struct file *file,
3287 const char __user *user_buf,
3288 size_t count, loff_t *ppos)
3289{
3290 struct hci_dev *hdev = file->private_data;
3291 char buf[32];
3292 size_t buf_size = min(count, (sizeof(buf) - 1));
3293 u8 key_size;
3294
3295 if (copy_from_user(buf, user_buf, buf_size))
3296 return -EFAULT;
3297
3298 buf[buf_size] = '\0';
3299
3300 sscanf(buf, "%hhu", &key_size);
3301
3302 if (key_size > SMP_DEV(hdev)->max_key_size ||
3303 key_size < SMP_MIN_ENC_KEY_SIZE)
3304 return -EINVAL;
3305
3306 SMP_DEV(hdev)->min_key_size = key_size;
3307
3308 return count;
3309}
3310
3311static const struct file_operations le_min_key_size_fops = {
3312 .open = simple_open,
3313 .read = le_min_key_size_read,
3314 .write = le_min_key_size_write,
3315 .llseek = default_llseek,
3316};
3317
3318static ssize_t le_max_key_size_read(struct file *file,
3319 char __user *user_buf,
3320 size_t count, loff_t *ppos)
3321{
3322 struct hci_dev *hdev = file->private_data;
3323 char buf[4];
3324
3325 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->max_key_size);
3326
3327 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf));
3328}
3329
3330static ssize_t le_max_key_size_write(struct file *file,
3331 const char __user *user_buf,
3332 size_t count, loff_t *ppos)
3333{
3334 struct hci_dev *hdev = file->private_data;
3335 char buf[32];
3336 size_t buf_size = min(count, (sizeof(buf) - 1));
3337 u8 key_size;
3338
3339 if (copy_from_user(buf, user_buf, buf_size))
3340 return -EFAULT;
3341
3342 buf[buf_size] = '\0';
3343
3344 sscanf(buf, "%hhu", &key_size);
3345
3346 if (key_size > SMP_MAX_ENC_KEY_SIZE ||
3347 key_size < SMP_DEV(hdev)->min_key_size)
3348 return -EINVAL;
3349
3350 SMP_DEV(hdev)->max_key_size = key_size;
3351
3352 return count;
3353}
3354
3355static const struct file_operations le_max_key_size_fops = {
3356 .open = simple_open,
3357 .read = le_max_key_size_read,
3358 .write = le_max_key_size_write,
3359 .llseek = default_llseek,
3360};
3361
3362int smp_register(struct hci_dev *hdev)
3363{
3364 struct l2cap_chan *chan;
3365
3366 BT_DBG("%s", hdev->name);
3367
3368 /* If the controller does not support Low Energy operation, then
3369 * there is also no need to register any SMP channel.
3370 */
3371 if (!lmp_le_capable(hdev))
3372 return 0;
3373
3374 if (WARN_ON(hdev->smp_data)) {
3375 chan = hdev->smp_data;
3376 hdev->smp_data = NULL;
3377 smp_del_chan(chan);
3378 }
3379
3380 chan = smp_add_cid(hdev, L2CAP_CID_SMP);
3381 if (IS_ERR(chan))
3382 return PTR_ERR(chan);
3383
3384 hdev->smp_data = chan;
3385
3386 debugfs_create_file("le_min_key_size", 0644, hdev->debugfs, hdev,
3387 &le_min_key_size_fops);
3388 debugfs_create_file("le_max_key_size", 0644, hdev->debugfs, hdev,
3389 &le_max_key_size_fops);
3390
3391 /* If the controller does not support BR/EDR Secure Connections
3392 * feature, then the BR/EDR SMP channel shall not be present.
3393 *
3394 * To test this with Bluetooth 4.0 controllers, create a debugfs
3395 * switch that allows forcing BR/EDR SMP support and accepting
3396 * cross-transport pairing on non-AES encrypted connections.
3397 */
3398 if (!lmp_sc_capable(hdev)) {
3399 debugfs_create_file("force_bredr_smp", 0644, hdev->debugfs,
3400 hdev, &force_bredr_smp_fops);
3401 return 0;
3402 }
3403
3404 if (WARN_ON(hdev->smp_bredr_data)) {
3405 chan = hdev->smp_bredr_data;
3406 hdev->smp_bredr_data = NULL;
3407 smp_del_chan(chan);
3408 }
3409
3410 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3411 if (IS_ERR(chan)) {
3412 int err = PTR_ERR(chan);
3413 chan = hdev->smp_data;
3414 hdev->smp_data = NULL;
3415 smp_del_chan(chan);
3416 return err;
3417 }
3418
3419 hdev->smp_bredr_data = chan;
3420
3421 return 0;
3422}
3423
3424void smp_unregister(struct hci_dev *hdev)
3425{
3426 struct l2cap_chan *chan;
3427
3428 if (hdev->smp_bredr_data) {
3429 chan = hdev->smp_bredr_data;
3430 hdev->smp_bredr_data = NULL;
3431 smp_del_chan(chan);
3432 }
3433
3434 if (hdev->smp_data) {
3435 chan = hdev->smp_data;
3436 hdev->smp_data = NULL;
3437 smp_del_chan(chan);
3438 }
3439}
3440
3441#if IS_ENABLED(CONFIG_BT_SELFTEST_SMP)
3442
3443static int __init test_ah(struct crypto_skcipher *tfm_aes)
3444{
3445 const u8 irk[16] = {
3446 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3447 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3448 const u8 r[3] = { 0x94, 0x81, 0x70 };
3449 const u8 exp[3] = { 0xaa, 0xfb, 0x0d };
3450 u8 res[3];
3451 int err;
3452
3453 err = smp_ah(tfm_aes, irk, r, res);
3454 if (err)
3455 return err;
3456
3457 if (memcmp(res, exp, 3))
3458 return -EINVAL;
3459
3460 return 0;
3461}
3462
3463static int __init test_c1(struct crypto_skcipher *tfm_aes)
3464{
3465 const u8 k[16] = {
3466 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
3467 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
3468 const u8 r[16] = {
3469 0xe0, 0x2e, 0x70, 0xc6, 0x4e, 0x27, 0x88, 0x63,
3470 0x0e, 0x6f, 0xad, 0x56, 0x21, 0xd5, 0x83, 0x57 };
3471 const u8 preq[7] = { 0x01, 0x01, 0x00, 0x00, 0x10, 0x07, 0x07 };
3472 const u8 pres[7] = { 0x02, 0x03, 0x00, 0x00, 0x08, 0x00, 0x05 };
3473 const u8 _iat = 0x01;
3474 const u8 _rat = 0x00;
3475 const bdaddr_t ra = { { 0xb6, 0xb5, 0xb4, 0xb3, 0xb2, 0xb1 } };
3476 const bdaddr_t ia = { { 0xa6, 0xa5, 0xa4, 0xa3, 0xa2, 0xa1 } };
3477 const u8 exp[16] = {
3478 0x86, 0x3b, 0xf1, 0xbe, 0xc5, 0x4d, 0xa7, 0xd2,
3479 0xea, 0x88, 0x89, 0x87, 0xef, 0x3f, 0x1e, 0x1e };
3480 u8 res[16];
3481 int err;
3482
3483 err = smp_c1(tfm_aes, k, r, preq, pres, _iat, &ia, _rat, &ra, res);
3484 if (err)
3485 return err;
3486
3487 if (memcmp(res, exp, 16))
3488 return -EINVAL;
3489
3490 return 0;
3491}
3492
3493static int __init test_s1(struct crypto_skcipher *tfm_aes)
3494{
3495 const u8 k[16] = {
3496 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
3497 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
3498 const u8 r1[16] = {
3499 0x88, 0x77, 0x66, 0x55, 0x44, 0x33, 0x22, 0x11 };
3500 const u8 r2[16] = {
3501 0x00, 0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa, 0x99 };
3502 const u8 exp[16] = {
3503 0x62, 0xa0, 0x6d, 0x79, 0xae, 0x16, 0x42, 0x5b,
3504 0x9b, 0xf4, 0xb0, 0xe8, 0xf0, 0xe1, 0x1f, 0x9a };
3505 u8 res[16];
3506 int err;
3507
3508 err = smp_s1(tfm_aes, k, r1, r2, res);
3509 if (err)
3510 return err;
3511
3512 if (memcmp(res, exp, 16))
3513 return -EINVAL;
3514
3515 return 0;
3516}
3517
3518static int __init test_f4(struct crypto_shash *tfm_cmac)
3519{
3520 const u8 u[32] = {
3521 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
3522 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
3523 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
3524 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 };
3525 const u8 v[32] = {
3526 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b,
3527 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59,
3528 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90,
3529 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 };
3530 const u8 x[16] = {
3531 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3532 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3533 const u8 z = 0x00;
3534 const u8 exp[16] = {
3535 0x2d, 0x87, 0x74, 0xa9, 0xbe, 0xa1, 0xed, 0xf1,
3536 0x1c, 0xbd, 0xa9, 0x07, 0xf1, 0x16, 0xc9, 0xf2 };
3537 u8 res[16];
3538 int err;
3539
3540 err = smp_f4(tfm_cmac, u, v, x, z, res);
3541 if (err)
3542 return err;
3543
3544 if (memcmp(res, exp, 16))
3545 return -EINVAL;
3546
3547 return 0;
3548}
3549
3550static int __init test_f5(struct crypto_shash *tfm_cmac)
3551{
3552 const u8 w[32] = {
3553 0x98, 0xa6, 0xbf, 0x73, 0xf3, 0x34, 0x8d, 0x86,
3554 0xf1, 0x66, 0xf8, 0xb4, 0x13, 0x6b, 0x79, 0x99,
3555 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3556 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3557 const u8 n1[16] = {
3558 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3559 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3560 const u8 n2[16] = {
3561 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3562 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3563 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 };
3564 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 };
3565 const u8 exp_ltk[16] = {
3566 0x38, 0x0a, 0x75, 0x94, 0xb5, 0x22, 0x05, 0x98,
3567 0x23, 0xcd, 0xd7, 0x69, 0x11, 0x79, 0x86, 0x69 };
3568 const u8 exp_mackey[16] = {
3569 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd,
3570 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 };
3571 u8 mackey[16], ltk[16];
3572 int err;
3573
3574 err = smp_f5(tfm_cmac, w, n1, n2, a1, a2, mackey, ltk);
3575 if (err)
3576 return err;
3577
3578 if (memcmp(mackey, exp_mackey, 16))
3579 return -EINVAL;
3580
3581 if (memcmp(ltk, exp_ltk, 16))
3582 return -EINVAL;
3583
3584 return 0;
3585}
3586
3587static int __init test_f6(struct crypto_shash *tfm_cmac)
3588{
3589 const u8 w[16] = {
3590 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd,
3591 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 };
3592 const u8 n1[16] = {
3593 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3594 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3595 const u8 n2[16] = {
3596 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3597 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3598 const u8 r[16] = {
3599 0xc8, 0x0f, 0x2d, 0x0c, 0xd2, 0x42, 0xda, 0x08,
3600 0x54, 0xbb, 0x53, 0xb4, 0x3b, 0x34, 0xa3, 0x12 };
3601 const u8 io_cap[3] = { 0x02, 0x01, 0x01 };
3602 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 };
3603 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 };
3604 const u8 exp[16] = {
3605 0x61, 0x8f, 0x95, 0xda, 0x09, 0x0b, 0x6c, 0xd2,
3606 0xc5, 0xe8, 0xd0, 0x9c, 0x98, 0x73, 0xc4, 0xe3 };
3607 u8 res[16];
3608 int err;
3609
3610 err = smp_f6(tfm_cmac, w, n1, n2, r, io_cap, a1, a2, res);
3611 if (err)
3612 return err;
3613
3614 if (memcmp(res, exp, 16))
3615 return -EINVAL;
3616
3617 return 0;
3618}
3619
3620static int __init test_g2(struct crypto_shash *tfm_cmac)
3621{
3622 const u8 u[32] = {
3623 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
3624 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
3625 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
3626 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 };
3627 const u8 v[32] = {
3628 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b,
3629 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59,
3630 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90,
3631 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 };
3632 const u8 x[16] = {
3633 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3634 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3635 const u8 y[16] = {
3636 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3637 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3638 const u32 exp_val = 0x2f9ed5ba % 1000000;
3639 u32 val;
3640 int err;
3641
3642 err = smp_g2(tfm_cmac, u, v, x, y, &val);
3643 if (err)
3644 return err;
3645
3646 if (val != exp_val)
3647 return -EINVAL;
3648
3649 return 0;
3650}
3651
3652static int __init test_h6(struct crypto_shash *tfm_cmac)
3653{
3654 const u8 w[16] = {
3655 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3656 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3657 const u8 key_id[4] = { 0x72, 0x62, 0x65, 0x6c };
3658 const u8 exp[16] = {
3659 0x99, 0x63, 0xb1, 0x80, 0xe2, 0xa9, 0xd3, 0xe8,
3660 0x1c, 0xc9, 0x6d, 0xe7, 0x02, 0xe1, 0x9a, 0x2d };
3661 u8 res[16];
3662 int err;
3663
3664 err = smp_h6(tfm_cmac, w, key_id, res);
3665 if (err)
3666 return err;
3667
3668 if (memcmp(res, exp, 16))
3669 return -EINVAL;
3670
3671 return 0;
3672}
3673
3674static char test_smp_buffer[32];
3675
3676static ssize_t test_smp_read(struct file *file, char __user *user_buf,
3677 size_t count, loff_t *ppos)
3678{
3679 return simple_read_from_buffer(user_buf, count, ppos, test_smp_buffer,
3680 strlen(test_smp_buffer));
3681}
3682
3683static const struct file_operations test_smp_fops = {
3684 .open = simple_open,
3685 .read = test_smp_read,
3686 .llseek = default_llseek,
3687};
3688
3689static int __init run_selftests(struct crypto_skcipher *tfm_aes,
3690 struct crypto_shash *tfm_cmac)
3691{
3692 ktime_t calltime, delta, rettime;
3693 unsigned long long duration;
3694 int err;
3695
3696 calltime = ktime_get();
3697
3698 err = test_ah(tfm_aes);
3699 if (err) {
3700 BT_ERR("smp_ah test failed");
3701 goto done;
3702 }
3703
3704 err = test_c1(tfm_aes);
3705 if (err) {
3706 BT_ERR("smp_c1 test failed");
3707 goto done;
3708 }
3709
3710 err = test_s1(tfm_aes);
3711 if (err) {
3712 BT_ERR("smp_s1 test failed");
3713 goto done;
3714 }
3715
3716 err = test_f4(tfm_cmac);
3717 if (err) {
3718 BT_ERR("smp_f4 test failed");
3719 goto done;
3720 }
3721
3722 err = test_f5(tfm_cmac);
3723 if (err) {
3724 BT_ERR("smp_f5 test failed");
3725 goto done;
3726 }
3727
3728 err = test_f6(tfm_cmac);
3729 if (err) {
3730 BT_ERR("smp_f6 test failed");
3731 goto done;
3732 }
3733
3734 err = test_g2(tfm_cmac);
3735 if (err) {
3736 BT_ERR("smp_g2 test failed");
3737 goto done;
3738 }
3739
3740 err = test_h6(tfm_cmac);
3741 if (err) {
3742 BT_ERR("smp_h6 test failed");
3743 goto done;
3744 }
3745
3746 rettime = ktime_get();
3747 delta = ktime_sub(rettime, calltime);
3748 duration = (unsigned long long) ktime_to_ns(delta) >> 10;
3749
3750 BT_INFO("SMP test passed in %llu usecs", duration);
3751
3752done:
3753 if (!err)
3754 snprintf(test_smp_buffer, sizeof(test_smp_buffer),
3755 "PASS (%llu usecs)\n", duration);
3756 else
3757 snprintf(test_smp_buffer, sizeof(test_smp_buffer), "FAIL\n");
3758
3759 debugfs_create_file("selftest_smp", 0444, bt_debugfs, NULL,
3760 &test_smp_fops);
3761
3762 return err;
3763}
3764
3765int __init bt_selftest_smp(void)
3766{
3767 struct crypto_skcipher *tfm_aes;
3768 struct crypto_shash *tfm_cmac;
3769 int err;
3770
3771 tfm_aes = crypto_alloc_skcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
3772 if (IS_ERR(tfm_aes)) {
3773 BT_ERR("Unable to create ECB crypto context");
3774 return PTR_ERR(tfm_aes);
3775 }
3776
3777 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, CRYPTO_ALG_ASYNC);
3778 if (IS_ERR(tfm_cmac)) {
3779 BT_ERR("Unable to create CMAC crypto context");
3780 crypto_free_skcipher(tfm_aes);
3781 return PTR_ERR(tfm_cmac);
3782 }
3783
3784 err = run_selftests(tfm_aes, tfm_cmac);
3785
3786 crypto_free_shash(tfm_cmac);
3787 crypto_free_skcipher(tfm_aes);
3788
3789 return err;
3790}
3791
3792#endif
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/aes.h>
27#include <crypto/algapi.h>
28#include <crypto/hash.h>
29#include <crypto/kpp.h>
30
31#include <net/bluetooth/bluetooth.h>
32#include <net/bluetooth/hci_core.h>
33#include <net/bluetooth/l2cap.h>
34#include <net/bluetooth/mgmt.h>
35
36#include "ecdh_helper.h"
37#include "smp.h"
38
39#define SMP_DEV(hdev) \
40 ((struct smp_dev *)((struct l2cap_chan *)((hdev)->smp_data))->data)
41
42/* Low-level debug macros to be used for stuff that we don't want
43 * accidentally in dmesg, i.e. the values of the various crypto keys
44 * and the inputs & outputs of crypto functions.
45 */
46#ifdef DEBUG
47#define SMP_DBG(fmt, ...) printk(KERN_DEBUG "%s: " fmt, __func__, \
48 ##__VA_ARGS__)
49#else
50#define SMP_DBG(fmt, ...) no_printk(KERN_DEBUG "%s: " fmt, __func__, \
51 ##__VA_ARGS__)
52#endif
53
54#define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd)
55
56/* Keys which are not distributed with Secure Connections */
57#define SMP_SC_NO_DIST (SMP_DIST_ENC_KEY | SMP_DIST_LINK_KEY)
58
59#define SMP_TIMEOUT msecs_to_jiffies(30000)
60
61#define AUTH_REQ_MASK(dev) (hci_dev_test_flag(dev, HCI_SC_ENABLED) ? \
62 0x3f : 0x07)
63#define KEY_DIST_MASK 0x07
64
65/* Maximum message length that can be passed to aes_cmac */
66#define CMAC_MSG_MAX 80
67
68enum {
69 SMP_FLAG_TK_VALID,
70 SMP_FLAG_CFM_PENDING,
71 SMP_FLAG_MITM_AUTH,
72 SMP_FLAG_COMPLETE,
73 SMP_FLAG_INITIATOR,
74 SMP_FLAG_SC,
75 SMP_FLAG_REMOTE_PK,
76 SMP_FLAG_DEBUG_KEY,
77 SMP_FLAG_WAIT_USER,
78 SMP_FLAG_DHKEY_PENDING,
79 SMP_FLAG_REMOTE_OOB,
80 SMP_FLAG_LOCAL_OOB,
81 SMP_FLAG_CT2,
82};
83
84struct smp_dev {
85 /* Secure Connections OOB data */
86 bool local_oob;
87 u8 local_pk[64];
88 u8 local_rand[16];
89 bool debug_key;
90
91 struct crypto_shash *tfm_cmac;
92 struct crypto_kpp *tfm_ecdh;
93};
94
95struct smp_chan {
96 struct l2cap_conn *conn;
97 struct delayed_work security_timer;
98 unsigned long allow_cmd; /* Bitmask of allowed commands */
99
100 u8 preq[7]; /* SMP Pairing Request */
101 u8 prsp[7]; /* SMP Pairing Response */
102 u8 prnd[16]; /* SMP Pairing Random (local) */
103 u8 rrnd[16]; /* SMP Pairing Random (remote) */
104 u8 pcnf[16]; /* SMP Pairing Confirm */
105 u8 tk[16]; /* SMP Temporary Key */
106 u8 rr[16]; /* Remote OOB ra/rb value */
107 u8 lr[16]; /* Local OOB ra/rb value */
108 u8 enc_key_size;
109 u8 remote_key_dist;
110 bdaddr_t id_addr;
111 u8 id_addr_type;
112 u8 irk[16];
113 struct smp_csrk *csrk;
114 struct smp_csrk *responder_csrk;
115 struct smp_ltk *ltk;
116 struct smp_ltk *responder_ltk;
117 struct smp_irk *remote_irk;
118 u8 *link_key;
119 unsigned long flags;
120 u8 method;
121 u8 passkey_round;
122
123 /* Secure Connections variables */
124 u8 local_pk[64];
125 u8 remote_pk[64];
126 u8 dhkey[32];
127 u8 mackey[16];
128
129 struct crypto_shash *tfm_cmac;
130 struct crypto_kpp *tfm_ecdh;
131};
132
133/* These debug key values are defined in the SMP section of the core
134 * specification. debug_pk is the public debug key and debug_sk the
135 * private debug key.
136 */
137static const u8 debug_pk[64] = {
138 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
139 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
140 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
141 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20,
142
143 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74,
144 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76,
145 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63,
146 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc,
147};
148
149static const u8 debug_sk[32] = {
150 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58,
151 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a,
152 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74,
153 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f,
154};
155
156static inline void swap_buf(const u8 *src, u8 *dst, size_t len)
157{
158 size_t i;
159
160 for (i = 0; i < len; i++)
161 dst[len - 1 - i] = src[i];
162}
163
164/* The following functions map to the LE SC SMP crypto functions
165 * AES-CMAC, f4, f5, f6, g2 and h6.
166 */
167
168static int aes_cmac(struct crypto_shash *tfm, const u8 k[16], const u8 *m,
169 size_t len, u8 mac[16])
170{
171 uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX];
172 int err;
173
174 if (len > CMAC_MSG_MAX)
175 return -EFBIG;
176
177 if (!tfm) {
178 BT_ERR("tfm %p", tfm);
179 return -EINVAL;
180 }
181
182 /* Swap key and message from LSB to MSB */
183 swap_buf(k, tmp, 16);
184 swap_buf(m, msg_msb, len);
185
186 SMP_DBG("msg (len %zu) %*phN", len, (int) len, m);
187 SMP_DBG("key %16phN", k);
188
189 err = crypto_shash_setkey(tfm, tmp, 16);
190 if (err) {
191 BT_ERR("cipher setkey failed: %d", err);
192 return err;
193 }
194
195 err = crypto_shash_tfm_digest(tfm, msg_msb, len, mac_msb);
196 if (err) {
197 BT_ERR("Hash computation error %d", err);
198 return err;
199 }
200
201 swap_buf(mac_msb, mac, 16);
202
203 SMP_DBG("mac %16phN", mac);
204
205 return 0;
206}
207
208static int smp_f4(struct crypto_shash *tfm_cmac, const u8 u[32],
209 const u8 v[32], const u8 x[16], u8 z, u8 res[16])
210{
211 u8 m[65];
212 int err;
213
214 SMP_DBG("u %32phN", u);
215 SMP_DBG("v %32phN", v);
216 SMP_DBG("x %16phN z %02x", x, z);
217
218 m[0] = z;
219 memcpy(m + 1, v, 32);
220 memcpy(m + 33, u, 32);
221
222 err = aes_cmac(tfm_cmac, x, m, sizeof(m), res);
223 if (err)
224 return err;
225
226 SMP_DBG("res %16phN", res);
227
228 return err;
229}
230
231static int smp_f5(struct crypto_shash *tfm_cmac, const u8 w[32],
232 const u8 n1[16], const u8 n2[16], const u8 a1[7],
233 const u8 a2[7], u8 mackey[16], u8 ltk[16])
234{
235 /* The btle, salt and length "magic" values are as defined in
236 * the SMP section of the Bluetooth core specification. In ASCII
237 * the btle value ends up being 'btle'. The salt is just a
238 * random number whereas length is the value 256 in little
239 * endian format.
240 */
241 const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 };
242 const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60,
243 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c };
244 const u8 length[2] = { 0x00, 0x01 };
245 u8 m[53], t[16];
246 int err;
247
248 SMP_DBG("w %32phN", w);
249 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
250 SMP_DBG("a1 %7phN a2 %7phN", a1, a2);
251
252 err = aes_cmac(tfm_cmac, salt, w, 32, t);
253 if (err)
254 return err;
255
256 SMP_DBG("t %16phN", t);
257
258 memcpy(m, length, 2);
259 memcpy(m + 2, a2, 7);
260 memcpy(m + 9, a1, 7);
261 memcpy(m + 16, n2, 16);
262 memcpy(m + 32, n1, 16);
263 memcpy(m + 48, btle, 4);
264
265 m[52] = 0; /* Counter */
266
267 err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey);
268 if (err)
269 return err;
270
271 SMP_DBG("mackey %16phN", mackey);
272
273 m[52] = 1; /* Counter */
274
275 err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk);
276 if (err)
277 return err;
278
279 SMP_DBG("ltk %16phN", ltk);
280
281 return 0;
282}
283
284static int smp_f6(struct crypto_shash *tfm_cmac, const u8 w[16],
285 const u8 n1[16], const u8 n2[16], const u8 r[16],
286 const u8 io_cap[3], const u8 a1[7], const u8 a2[7],
287 u8 res[16])
288{
289 u8 m[65];
290 int err;
291
292 SMP_DBG("w %16phN", w);
293 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
294 SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2);
295
296 memcpy(m, a2, 7);
297 memcpy(m + 7, a1, 7);
298 memcpy(m + 14, io_cap, 3);
299 memcpy(m + 17, r, 16);
300 memcpy(m + 33, n2, 16);
301 memcpy(m + 49, n1, 16);
302
303 err = aes_cmac(tfm_cmac, w, m, sizeof(m), res);
304 if (err)
305 return err;
306
307 SMP_DBG("res %16phN", res);
308
309 return err;
310}
311
312static int smp_g2(struct crypto_shash *tfm_cmac, const u8 u[32], const u8 v[32],
313 const u8 x[16], const u8 y[16], u32 *val)
314{
315 u8 m[80], tmp[16];
316 int err;
317
318 SMP_DBG("u %32phN", u);
319 SMP_DBG("v %32phN", v);
320 SMP_DBG("x %16phN y %16phN", x, y);
321
322 memcpy(m, y, 16);
323 memcpy(m + 16, v, 32);
324 memcpy(m + 48, u, 32);
325
326 err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp);
327 if (err)
328 return err;
329
330 *val = get_unaligned_le32(tmp);
331 *val %= 1000000;
332
333 SMP_DBG("val %06u", *val);
334
335 return 0;
336}
337
338static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16],
339 const u8 key_id[4], u8 res[16])
340{
341 int err;
342
343 SMP_DBG("w %16phN key_id %4phN", w, key_id);
344
345 err = aes_cmac(tfm_cmac, w, key_id, 4, res);
346 if (err)
347 return err;
348
349 SMP_DBG("res %16phN", res);
350
351 return err;
352}
353
354static int smp_h7(struct crypto_shash *tfm_cmac, const u8 w[16],
355 const u8 salt[16], u8 res[16])
356{
357 int err;
358
359 SMP_DBG("w %16phN salt %16phN", w, salt);
360
361 err = aes_cmac(tfm_cmac, salt, w, 16, res);
362 if (err)
363 return err;
364
365 SMP_DBG("res %16phN", res);
366
367 return err;
368}
369
370/* The following functions map to the legacy SMP crypto functions e, c1,
371 * s1 and ah.
372 */
373
374static int smp_e(const u8 *k, u8 *r)
375{
376 struct crypto_aes_ctx ctx;
377 uint8_t tmp[16], data[16];
378 int err;
379
380 SMP_DBG("k %16phN r %16phN", k, r);
381
382 /* The most significant octet of key corresponds to k[0] */
383 swap_buf(k, tmp, 16);
384
385 err = aes_expandkey(&ctx, tmp, 16);
386 if (err) {
387 BT_ERR("cipher setkey failed: %d", err);
388 return err;
389 }
390
391 /* Most significant octet of plaintextData corresponds to data[0] */
392 swap_buf(r, data, 16);
393
394 aes_encrypt(&ctx, data, data);
395
396 /* Most significant octet of encryptedData corresponds to data[0] */
397 swap_buf(data, r, 16);
398
399 SMP_DBG("r %16phN", r);
400
401 memzero_explicit(&ctx, sizeof(ctx));
402 return err;
403}
404
405static int smp_c1(const u8 k[16],
406 const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat,
407 const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16])
408{
409 u8 p1[16], p2[16];
410 int err;
411
412 SMP_DBG("k %16phN r %16phN", k, r);
413 SMP_DBG("iat %u ia %6phN rat %u ra %6phN", _iat, ia, _rat, ra);
414 SMP_DBG("preq %7phN pres %7phN", preq, pres);
415
416 memset(p1, 0, 16);
417
418 /* p1 = pres || preq || _rat || _iat */
419 p1[0] = _iat;
420 p1[1] = _rat;
421 memcpy(p1 + 2, preq, 7);
422 memcpy(p1 + 9, pres, 7);
423
424 SMP_DBG("p1 %16phN", p1);
425
426 /* res = r XOR p1 */
427 crypto_xor_cpy(res, r, p1, sizeof(p1));
428
429 /* res = e(k, res) */
430 err = smp_e(k, res);
431 if (err) {
432 BT_ERR("Encrypt data error");
433 return err;
434 }
435
436 /* p2 = padding || ia || ra */
437 memcpy(p2, ra, 6);
438 memcpy(p2 + 6, ia, 6);
439 memset(p2 + 12, 0, 4);
440
441 SMP_DBG("p2 %16phN", p2);
442
443 /* res = res XOR p2 */
444 crypto_xor(res, p2, sizeof(p2));
445
446 /* res = e(k, res) */
447 err = smp_e(k, res);
448 if (err)
449 BT_ERR("Encrypt data error");
450
451 return err;
452}
453
454static int smp_s1(const u8 k[16],
455 const u8 r1[16], const u8 r2[16], u8 _r[16])
456{
457 int err;
458
459 /* Just least significant octets from r1 and r2 are considered */
460 memcpy(_r, r2, 8);
461 memcpy(_r + 8, r1, 8);
462
463 err = smp_e(k, _r);
464 if (err)
465 BT_ERR("Encrypt data error");
466
467 return err;
468}
469
470static int smp_ah(const u8 irk[16], const u8 r[3], u8 res[3])
471{
472 u8 _res[16];
473 int err;
474
475 /* r' = padding || r */
476 memcpy(_res, r, 3);
477 memset(_res + 3, 0, 13);
478
479 err = smp_e(irk, _res);
480 if (err) {
481 BT_ERR("Encrypt error");
482 return err;
483 }
484
485 /* The output of the random address function ah is:
486 * ah(k, r) = e(k, r') mod 2^24
487 * The output of the security function e is then truncated to 24 bits
488 * by taking the least significant 24 bits of the output of e as the
489 * result of ah.
490 */
491 memcpy(res, _res, 3);
492
493 return 0;
494}
495
496bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16],
497 const bdaddr_t *bdaddr)
498{
499 struct l2cap_chan *chan = hdev->smp_data;
500 u8 hash[3];
501 int err;
502
503 if (!chan || !chan->data)
504 return false;
505
506 bt_dev_dbg(hdev, "RPA %pMR IRK %*phN", bdaddr, 16, irk);
507
508 err = smp_ah(irk, &bdaddr->b[3], hash);
509 if (err)
510 return false;
511
512 return !crypto_memneq(bdaddr->b, hash, 3);
513}
514
515int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa)
516{
517 struct l2cap_chan *chan = hdev->smp_data;
518 int err;
519
520 if (!chan || !chan->data)
521 return -EOPNOTSUPP;
522
523 get_random_bytes(&rpa->b[3], 3);
524
525 rpa->b[5] &= 0x3f; /* Clear two most significant bits */
526 rpa->b[5] |= 0x40; /* Set second most significant bit */
527
528 err = smp_ah(irk, &rpa->b[3], rpa->b);
529 if (err < 0)
530 return err;
531
532 bt_dev_dbg(hdev, "RPA %pMR", rpa);
533
534 return 0;
535}
536
537int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16])
538{
539 struct l2cap_chan *chan = hdev->smp_data;
540 struct smp_dev *smp;
541 int err;
542
543 if (!chan || !chan->data)
544 return -EOPNOTSUPP;
545
546 smp = chan->data;
547
548 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
549 bt_dev_dbg(hdev, "Using debug keys");
550 err = set_ecdh_privkey(smp->tfm_ecdh, debug_sk);
551 if (err)
552 return err;
553 memcpy(smp->local_pk, debug_pk, 64);
554 smp->debug_key = true;
555 } else {
556 while (true) {
557 /* Generate key pair for Secure Connections */
558 err = generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk);
559 if (err)
560 return err;
561
562 /* This is unlikely, but we need to check that
563 * we didn't accidentally generate a debug key.
564 */
565 if (crypto_memneq(smp->local_pk, debug_pk, 64))
566 break;
567 }
568 smp->debug_key = false;
569 }
570
571 SMP_DBG("OOB Public Key X: %32phN", smp->local_pk);
572 SMP_DBG("OOB Public Key Y: %32phN", smp->local_pk + 32);
573
574 get_random_bytes(smp->local_rand, 16);
575
576 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->local_pk,
577 smp->local_rand, 0, hash);
578 if (err < 0)
579 return err;
580
581 memcpy(rand, smp->local_rand, 16);
582
583 smp->local_oob = true;
584
585 return 0;
586}
587
588static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
589{
590 struct l2cap_chan *chan = conn->smp;
591 struct smp_chan *smp;
592 struct kvec iv[2];
593 struct msghdr msg;
594
595 if (!chan)
596 return;
597
598 bt_dev_dbg(conn->hcon->hdev, "code 0x%2.2x", code);
599
600 iv[0].iov_base = &code;
601 iv[0].iov_len = 1;
602
603 iv[1].iov_base = data;
604 iv[1].iov_len = len;
605
606 memset(&msg, 0, sizeof(msg));
607
608 iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, iv, 2, 1 + len);
609
610 l2cap_chan_send(chan, &msg, 1 + len);
611
612 if (!chan->data)
613 return;
614
615 smp = chan->data;
616
617 cancel_delayed_work_sync(&smp->security_timer);
618 schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT);
619}
620
621static u8 authreq_to_seclevel(u8 authreq)
622{
623 if (authreq & SMP_AUTH_MITM) {
624 if (authreq & SMP_AUTH_SC)
625 return BT_SECURITY_FIPS;
626 else
627 return BT_SECURITY_HIGH;
628 } else {
629 return BT_SECURITY_MEDIUM;
630 }
631}
632
633static __u8 seclevel_to_authreq(__u8 sec_level)
634{
635 switch (sec_level) {
636 case BT_SECURITY_FIPS:
637 case BT_SECURITY_HIGH:
638 return SMP_AUTH_MITM | SMP_AUTH_BONDING;
639 case BT_SECURITY_MEDIUM:
640 return SMP_AUTH_BONDING;
641 default:
642 return SMP_AUTH_NONE;
643 }
644}
645
646static void build_pairing_cmd(struct l2cap_conn *conn,
647 struct smp_cmd_pairing *req,
648 struct smp_cmd_pairing *rsp, __u8 authreq)
649{
650 struct l2cap_chan *chan = conn->smp;
651 struct smp_chan *smp = chan->data;
652 struct hci_conn *hcon = conn->hcon;
653 struct hci_dev *hdev = hcon->hdev;
654 u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT;
655
656 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
657 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
658 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
659 authreq |= SMP_AUTH_BONDING;
660 } else {
661 authreq &= ~SMP_AUTH_BONDING;
662 }
663
664 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
665 remote_dist |= SMP_DIST_ID_KEY;
666
667 if (hci_dev_test_flag(hdev, HCI_PRIVACY))
668 local_dist |= SMP_DIST_ID_KEY;
669
670 if (hci_dev_test_flag(hdev, HCI_SC_ENABLED) &&
671 (authreq & SMP_AUTH_SC)) {
672 struct oob_data *oob_data;
673 u8 bdaddr_type;
674
675 if (hci_dev_test_flag(hdev, HCI_SSP_ENABLED)) {
676 local_dist |= SMP_DIST_LINK_KEY;
677 remote_dist |= SMP_DIST_LINK_KEY;
678 }
679
680 if (hcon->dst_type == ADDR_LE_DEV_PUBLIC)
681 bdaddr_type = BDADDR_LE_PUBLIC;
682 else
683 bdaddr_type = BDADDR_LE_RANDOM;
684
685 oob_data = hci_find_remote_oob_data(hdev, &hcon->dst,
686 bdaddr_type);
687 if (oob_data && oob_data->present) {
688 set_bit(SMP_FLAG_REMOTE_OOB, &smp->flags);
689 oob_flag = SMP_OOB_PRESENT;
690 memcpy(smp->rr, oob_data->rand256, 16);
691 memcpy(smp->pcnf, oob_data->hash256, 16);
692 SMP_DBG("OOB Remote Confirmation: %16phN", smp->pcnf);
693 SMP_DBG("OOB Remote Random: %16phN", smp->rr);
694 }
695
696 } else {
697 authreq &= ~SMP_AUTH_SC;
698 }
699
700 if (rsp == NULL) {
701 req->io_capability = conn->hcon->io_capability;
702 req->oob_flag = oob_flag;
703 req->max_key_size = hdev->le_max_key_size;
704 req->init_key_dist = local_dist;
705 req->resp_key_dist = remote_dist;
706 req->auth_req = (authreq & AUTH_REQ_MASK(hdev));
707
708 smp->remote_key_dist = remote_dist;
709 return;
710 }
711
712 rsp->io_capability = conn->hcon->io_capability;
713 rsp->oob_flag = oob_flag;
714 rsp->max_key_size = hdev->le_max_key_size;
715 rsp->init_key_dist = req->init_key_dist & remote_dist;
716 rsp->resp_key_dist = req->resp_key_dist & local_dist;
717 rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev));
718
719 smp->remote_key_dist = rsp->init_key_dist;
720}
721
722static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)
723{
724 struct l2cap_chan *chan = conn->smp;
725 struct hci_dev *hdev = conn->hcon->hdev;
726 struct smp_chan *smp = chan->data;
727
728 if (conn->hcon->pending_sec_level == BT_SECURITY_FIPS &&
729 max_key_size != SMP_MAX_ENC_KEY_SIZE)
730 return SMP_ENC_KEY_SIZE;
731
732 if (max_key_size > hdev->le_max_key_size ||
733 max_key_size < SMP_MIN_ENC_KEY_SIZE)
734 return SMP_ENC_KEY_SIZE;
735
736 smp->enc_key_size = max_key_size;
737
738 return 0;
739}
740
741static void smp_chan_destroy(struct l2cap_conn *conn)
742{
743 struct l2cap_chan *chan = conn->smp;
744 struct smp_chan *smp = chan->data;
745 struct hci_conn *hcon = conn->hcon;
746 bool complete;
747
748 BUG_ON(!smp);
749
750 cancel_delayed_work_sync(&smp->security_timer);
751
752 complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags);
753 mgmt_smp_complete(hcon, complete);
754
755 kfree_sensitive(smp->csrk);
756 kfree_sensitive(smp->responder_csrk);
757 kfree_sensitive(smp->link_key);
758
759 crypto_free_shash(smp->tfm_cmac);
760 crypto_free_kpp(smp->tfm_ecdh);
761
762 /* Ensure that we don't leave any debug key around if debug key
763 * support hasn't been explicitly enabled.
764 */
765 if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG &&
766 !hci_dev_test_flag(hcon->hdev, HCI_KEEP_DEBUG_KEYS)) {
767 list_del_rcu(&smp->ltk->list);
768 kfree_rcu(smp->ltk, rcu);
769 smp->ltk = NULL;
770 }
771
772 /* If pairing failed clean up any keys we might have */
773 if (!complete) {
774 if (smp->ltk) {
775 list_del_rcu(&smp->ltk->list);
776 kfree_rcu(smp->ltk, rcu);
777 }
778
779 if (smp->responder_ltk) {
780 list_del_rcu(&smp->responder_ltk->list);
781 kfree_rcu(smp->responder_ltk, rcu);
782 }
783
784 if (smp->remote_irk) {
785 list_del_rcu(&smp->remote_irk->list);
786 kfree_rcu(smp->remote_irk, rcu);
787 }
788 }
789
790 chan->data = NULL;
791 kfree_sensitive(smp);
792 hci_conn_drop(hcon);
793}
794
795static void smp_failure(struct l2cap_conn *conn, u8 reason)
796{
797 struct hci_conn *hcon = conn->hcon;
798 struct l2cap_chan *chan = conn->smp;
799
800 if (reason)
801 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
802 &reason);
803
804 mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE);
805
806 if (chan->data)
807 smp_chan_destroy(conn);
808}
809
810#define JUST_WORKS 0x00
811#define JUST_CFM 0x01
812#define REQ_PASSKEY 0x02
813#define CFM_PASSKEY 0x03
814#define REQ_OOB 0x04
815#define DSP_PASSKEY 0x05
816#define OVERLAP 0xFF
817
818static const u8 gen_method[5][5] = {
819 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
820 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
821 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
822 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
823 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP },
824};
825
826static const u8 sc_method[5][5] = {
827 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
828 { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
829 { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY },
830 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
831 { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
832};
833
834static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io)
835{
836 /* If either side has unknown io_caps, use JUST_CFM (which gets
837 * converted later to JUST_WORKS if we're initiators.
838 */
839 if (local_io > SMP_IO_KEYBOARD_DISPLAY ||
840 remote_io > SMP_IO_KEYBOARD_DISPLAY)
841 return JUST_CFM;
842
843 if (test_bit(SMP_FLAG_SC, &smp->flags))
844 return sc_method[remote_io][local_io];
845
846 return gen_method[remote_io][local_io];
847}
848
849static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
850 u8 local_io, u8 remote_io)
851{
852 struct hci_conn *hcon = conn->hcon;
853 struct l2cap_chan *chan = conn->smp;
854 struct smp_chan *smp = chan->data;
855 u32 passkey = 0;
856 int ret;
857
858 /* Initialize key for JUST WORKS */
859 memset(smp->tk, 0, sizeof(smp->tk));
860 clear_bit(SMP_FLAG_TK_VALID, &smp->flags);
861
862 bt_dev_dbg(hcon->hdev, "auth:%u lcl:%u rem:%u", auth, local_io,
863 remote_io);
864
865 /* If neither side wants MITM, either "just" confirm an incoming
866 * request or use just-works for outgoing ones. The JUST_CFM
867 * will be converted to JUST_WORKS if necessary later in this
868 * function. If either side has MITM look up the method from the
869 * table.
870 */
871 if (!(auth & SMP_AUTH_MITM))
872 smp->method = JUST_CFM;
873 else
874 smp->method = get_auth_method(smp, local_io, remote_io);
875
876 /* Don't confirm locally initiated pairing attempts */
877 if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR,
878 &smp->flags))
879 smp->method = JUST_WORKS;
880
881 /* Don't bother user space with no IO capabilities */
882 if (smp->method == JUST_CFM &&
883 hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
884 smp->method = JUST_WORKS;
885
886 /* If Just Works, Continue with Zero TK and ask user-space for
887 * confirmation */
888 if (smp->method == JUST_WORKS) {
889 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
890 hcon->type,
891 hcon->dst_type,
892 passkey, 1);
893 if (ret)
894 return ret;
895 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
896 return 0;
897 }
898
899 /* If this function is used for SC -> legacy fallback we
900 * can only recover the just-works case.
901 */
902 if (test_bit(SMP_FLAG_SC, &smp->flags))
903 return -EINVAL;
904
905 /* Not Just Works/Confirm results in MITM Authentication */
906 if (smp->method != JUST_CFM) {
907 set_bit(SMP_FLAG_MITM_AUTH, &smp->flags);
908 if (hcon->pending_sec_level < BT_SECURITY_HIGH)
909 hcon->pending_sec_level = BT_SECURITY_HIGH;
910 }
911
912 /* If both devices have Keyboard-Display I/O, the initiator
913 * Confirms and the responder Enters the passkey.
914 */
915 if (smp->method == OVERLAP) {
916 if (hcon->role == HCI_ROLE_MASTER)
917 smp->method = CFM_PASSKEY;
918 else
919 smp->method = REQ_PASSKEY;
920 }
921
922 /* Generate random passkey. */
923 if (smp->method == CFM_PASSKEY) {
924 memset(smp->tk, 0, sizeof(smp->tk));
925 get_random_bytes(&passkey, sizeof(passkey));
926 passkey %= 1000000;
927 put_unaligned_le32(passkey, smp->tk);
928 bt_dev_dbg(hcon->hdev, "PassKey: %u", passkey);
929 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
930 }
931
932 if (smp->method == REQ_PASSKEY)
933 ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst,
934 hcon->type, hcon->dst_type);
935 else if (smp->method == JUST_CFM)
936 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
937 hcon->type, hcon->dst_type,
938 passkey, 1);
939 else
940 ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst,
941 hcon->type, hcon->dst_type,
942 passkey, 0);
943
944 return ret;
945}
946
947static u8 smp_confirm(struct smp_chan *smp)
948{
949 struct l2cap_conn *conn = smp->conn;
950 struct smp_cmd_pairing_confirm cp;
951 int ret;
952
953 bt_dev_dbg(conn->hcon->hdev, "conn %p", conn);
954
955 ret = smp_c1(smp->tk, smp->prnd, smp->preq, smp->prsp,
956 conn->hcon->init_addr_type, &conn->hcon->init_addr,
957 conn->hcon->resp_addr_type, &conn->hcon->resp_addr,
958 cp.confirm_val);
959 if (ret)
960 return SMP_UNSPECIFIED;
961
962 clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
963
964 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
965
966 if (conn->hcon->out)
967 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
968 else
969 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
970
971 return 0;
972}
973
974static u8 smp_random(struct smp_chan *smp)
975{
976 struct l2cap_conn *conn = smp->conn;
977 struct hci_conn *hcon = conn->hcon;
978 u8 confirm[16];
979 int ret;
980
981 bt_dev_dbg(conn->hcon->hdev, "conn %p %s", conn,
982 conn->hcon->out ? "initiator" : "responder");
983
984 ret = smp_c1(smp->tk, smp->rrnd, smp->preq, smp->prsp,
985 hcon->init_addr_type, &hcon->init_addr,
986 hcon->resp_addr_type, &hcon->resp_addr, confirm);
987 if (ret)
988 return SMP_UNSPECIFIED;
989
990 if (crypto_memneq(smp->pcnf, confirm, sizeof(smp->pcnf))) {
991 bt_dev_err(hcon->hdev, "pairing failed "
992 "(confirmation values mismatch)");
993 return SMP_CONFIRM_FAILED;
994 }
995
996 if (hcon->out) {
997 u8 stk[16];
998 __le64 rand = 0;
999 __le16 ediv = 0;
1000
1001 smp_s1(smp->tk, smp->rrnd, smp->prnd, stk);
1002
1003 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
1004 return SMP_UNSPECIFIED;
1005
1006 hci_le_start_enc(hcon, ediv, rand, stk, smp->enc_key_size);
1007 hcon->enc_key_size = smp->enc_key_size;
1008 set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
1009 } else {
1010 u8 stk[16], auth;
1011 __le64 rand = 0;
1012 __le16 ediv = 0;
1013
1014 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1015 smp->prnd);
1016
1017 smp_s1(smp->tk, smp->prnd, smp->rrnd, stk);
1018
1019 if (hcon->pending_sec_level == BT_SECURITY_HIGH)
1020 auth = 1;
1021 else
1022 auth = 0;
1023
1024 /* Even though there's no _RESPONDER suffix this is the
1025 * responder STK we're adding for later lookup (the initiator
1026 * STK never needs to be stored).
1027 */
1028 hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1029 SMP_STK, auth, stk, smp->enc_key_size, ediv, rand);
1030 }
1031
1032 return 0;
1033}
1034
1035static void smp_notify_keys(struct l2cap_conn *conn)
1036{
1037 struct l2cap_chan *chan = conn->smp;
1038 struct smp_chan *smp = chan->data;
1039 struct hci_conn *hcon = conn->hcon;
1040 struct hci_dev *hdev = hcon->hdev;
1041 struct smp_cmd_pairing *req = (void *) &smp->preq[1];
1042 struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1];
1043 bool persistent;
1044
1045 if (hcon->type == ACL_LINK) {
1046 if (hcon->key_type == HCI_LK_DEBUG_COMBINATION)
1047 persistent = false;
1048 else
1049 persistent = !test_bit(HCI_CONN_FLUSH_KEY,
1050 &hcon->flags);
1051 } else {
1052 /* The LTKs, IRKs and CSRKs should be persistent only if
1053 * both sides had the bonding bit set in their
1054 * authentication requests.
1055 */
1056 persistent = !!((req->auth_req & rsp->auth_req) &
1057 SMP_AUTH_BONDING);
1058 }
1059
1060 if (smp->remote_irk) {
1061 mgmt_new_irk(hdev, smp->remote_irk, persistent);
1062
1063 /* Now that user space can be considered to know the
1064 * identity address track the connection based on it
1065 * from now on (assuming this is an LE link).
1066 */
1067 if (hcon->type == LE_LINK) {
1068 bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
1069 hcon->dst_type = smp->remote_irk->addr_type;
1070 queue_work(hdev->workqueue, &conn->id_addr_update_work);
1071 }
1072 }
1073
1074 if (smp->csrk) {
1075 smp->csrk->bdaddr_type = hcon->dst_type;
1076 bacpy(&smp->csrk->bdaddr, &hcon->dst);
1077 mgmt_new_csrk(hdev, smp->csrk, persistent);
1078 }
1079
1080 if (smp->responder_csrk) {
1081 smp->responder_csrk->bdaddr_type = hcon->dst_type;
1082 bacpy(&smp->responder_csrk->bdaddr, &hcon->dst);
1083 mgmt_new_csrk(hdev, smp->responder_csrk, persistent);
1084 }
1085
1086 if (smp->ltk) {
1087 smp->ltk->bdaddr_type = hcon->dst_type;
1088 bacpy(&smp->ltk->bdaddr, &hcon->dst);
1089 mgmt_new_ltk(hdev, smp->ltk, persistent);
1090 }
1091
1092 if (smp->responder_ltk) {
1093 smp->responder_ltk->bdaddr_type = hcon->dst_type;
1094 bacpy(&smp->responder_ltk->bdaddr, &hcon->dst);
1095 mgmt_new_ltk(hdev, smp->responder_ltk, persistent);
1096 }
1097
1098 if (smp->link_key) {
1099 struct link_key *key;
1100 u8 type;
1101
1102 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1103 type = HCI_LK_DEBUG_COMBINATION;
1104 else if (hcon->sec_level == BT_SECURITY_FIPS)
1105 type = HCI_LK_AUTH_COMBINATION_P256;
1106 else
1107 type = HCI_LK_UNAUTH_COMBINATION_P256;
1108
1109 key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst,
1110 smp->link_key, type, 0, &persistent);
1111 if (key) {
1112 mgmt_new_link_key(hdev, key, persistent);
1113
1114 /* Don't keep debug keys around if the relevant
1115 * flag is not set.
1116 */
1117 if (!hci_dev_test_flag(hdev, HCI_KEEP_DEBUG_KEYS) &&
1118 key->type == HCI_LK_DEBUG_COMBINATION) {
1119 list_del_rcu(&key->list);
1120 kfree_rcu(key, rcu);
1121 }
1122 }
1123 }
1124}
1125
1126static void sc_add_ltk(struct smp_chan *smp)
1127{
1128 struct hci_conn *hcon = smp->conn->hcon;
1129 u8 key_type, auth;
1130
1131 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1132 key_type = SMP_LTK_P256_DEBUG;
1133 else
1134 key_type = SMP_LTK_P256;
1135
1136 if (hcon->pending_sec_level == BT_SECURITY_FIPS)
1137 auth = 1;
1138 else
1139 auth = 0;
1140
1141 smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1142 key_type, auth, smp->tk, smp->enc_key_size,
1143 0, 0);
1144}
1145
1146static void sc_generate_link_key(struct smp_chan *smp)
1147{
1148 /* From core spec. Spells out in ASCII as 'lebr'. */
1149 const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c };
1150
1151 smp->link_key = kzalloc(16, GFP_KERNEL);
1152 if (!smp->link_key)
1153 return;
1154
1155 if (test_bit(SMP_FLAG_CT2, &smp->flags)) {
1156 /* SALT = 0x000000000000000000000000746D7031 */
1157 const u8 salt[16] = { 0x31, 0x70, 0x6d, 0x74 };
1158
1159 if (smp_h7(smp->tfm_cmac, smp->tk, salt, smp->link_key)) {
1160 kfree_sensitive(smp->link_key);
1161 smp->link_key = NULL;
1162 return;
1163 }
1164 } else {
1165 /* From core spec. Spells out in ASCII as 'tmp1'. */
1166 const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 };
1167
1168 if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) {
1169 kfree_sensitive(smp->link_key);
1170 smp->link_key = NULL;
1171 return;
1172 }
1173 }
1174
1175 if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) {
1176 kfree_sensitive(smp->link_key);
1177 smp->link_key = NULL;
1178 return;
1179 }
1180}
1181
1182static void smp_allow_key_dist(struct smp_chan *smp)
1183{
1184 /* Allow the first expected phase 3 PDU. The rest of the PDUs
1185 * will be allowed in each PDU handler to ensure we receive
1186 * them in the correct order.
1187 */
1188 if (smp->remote_key_dist & SMP_DIST_ENC_KEY)
1189 SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO);
1190 else if (smp->remote_key_dist & SMP_DIST_ID_KEY)
1191 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
1192 else if (smp->remote_key_dist & SMP_DIST_SIGN)
1193 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
1194}
1195
1196static void sc_generate_ltk(struct smp_chan *smp)
1197{
1198 /* From core spec. Spells out in ASCII as 'brle'. */
1199 const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 };
1200 struct hci_conn *hcon = smp->conn->hcon;
1201 struct hci_dev *hdev = hcon->hdev;
1202 struct link_key *key;
1203
1204 key = hci_find_link_key(hdev, &hcon->dst);
1205 if (!key) {
1206 bt_dev_err(hdev, "no Link Key found to generate LTK");
1207 return;
1208 }
1209
1210 if (key->type == HCI_LK_DEBUG_COMBINATION)
1211 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1212
1213 if (test_bit(SMP_FLAG_CT2, &smp->flags)) {
1214 /* SALT = 0x000000000000000000000000746D7032 */
1215 const u8 salt[16] = { 0x32, 0x70, 0x6d, 0x74 };
1216
1217 if (smp_h7(smp->tfm_cmac, key->val, salt, smp->tk))
1218 return;
1219 } else {
1220 /* From core spec. Spells out in ASCII as 'tmp2'. */
1221 const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 };
1222
1223 if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk))
1224 return;
1225 }
1226
1227 if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk))
1228 return;
1229
1230 sc_add_ltk(smp);
1231}
1232
1233static void smp_distribute_keys(struct smp_chan *smp)
1234{
1235 struct smp_cmd_pairing *req, *rsp;
1236 struct l2cap_conn *conn = smp->conn;
1237 struct hci_conn *hcon = conn->hcon;
1238 struct hci_dev *hdev = hcon->hdev;
1239 __u8 *keydist;
1240
1241 bt_dev_dbg(hdev, "conn %p", conn);
1242
1243 rsp = (void *) &smp->prsp[1];
1244
1245 /* The responder sends its keys first */
1246 if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) {
1247 smp_allow_key_dist(smp);
1248 return;
1249 }
1250
1251 req = (void *) &smp->preq[1];
1252
1253 if (hcon->out) {
1254 keydist = &rsp->init_key_dist;
1255 *keydist &= req->init_key_dist;
1256 } else {
1257 keydist = &rsp->resp_key_dist;
1258 *keydist &= req->resp_key_dist;
1259 }
1260
1261 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1262 if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY))
1263 sc_generate_link_key(smp);
1264 if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY))
1265 sc_generate_ltk(smp);
1266
1267 /* Clear the keys which are generated but not distributed */
1268 *keydist &= ~SMP_SC_NO_DIST;
1269 }
1270
1271 bt_dev_dbg(hdev, "keydist 0x%x", *keydist);
1272
1273 if (*keydist & SMP_DIST_ENC_KEY) {
1274 struct smp_cmd_encrypt_info enc;
1275 struct smp_cmd_initiator_ident ident;
1276 struct smp_ltk *ltk;
1277 u8 authenticated;
1278 __le16 ediv;
1279 __le64 rand;
1280
1281 /* Make sure we generate only the significant amount of
1282 * bytes based on the encryption key size, and set the rest
1283 * of the value to zeroes.
1284 */
1285 get_random_bytes(enc.ltk, smp->enc_key_size);
1286 memset(enc.ltk + smp->enc_key_size, 0,
1287 sizeof(enc.ltk) - smp->enc_key_size);
1288
1289 get_random_bytes(&ediv, sizeof(ediv));
1290 get_random_bytes(&rand, sizeof(rand));
1291
1292 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);
1293
1294 authenticated = hcon->sec_level == BT_SECURITY_HIGH;
1295 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type,
1296 SMP_LTK_RESPONDER, authenticated, enc.ltk,
1297 smp->enc_key_size, ediv, rand);
1298 smp->responder_ltk = ltk;
1299
1300 ident.ediv = ediv;
1301 ident.rand = rand;
1302
1303 smp_send_cmd(conn, SMP_CMD_INITIATOR_IDENT, sizeof(ident),
1304 &ident);
1305
1306 *keydist &= ~SMP_DIST_ENC_KEY;
1307 }
1308
1309 if (*keydist & SMP_DIST_ID_KEY) {
1310 struct smp_cmd_ident_addr_info addrinfo;
1311 struct smp_cmd_ident_info idinfo;
1312
1313 memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk));
1314
1315 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);
1316
1317 /* The hci_conn contains the local identity address
1318 * after the connection has been established.
1319 *
1320 * This is true even when the connection has been
1321 * established using a resolvable random address.
1322 */
1323 bacpy(&addrinfo.bdaddr, &hcon->src);
1324 addrinfo.addr_type = hcon->src_type;
1325
1326 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo),
1327 &addrinfo);
1328
1329 *keydist &= ~SMP_DIST_ID_KEY;
1330 }
1331
1332 if (*keydist & SMP_DIST_SIGN) {
1333 struct smp_cmd_sign_info sign;
1334 struct smp_csrk *csrk;
1335
1336 /* Generate a new random key */
1337 get_random_bytes(sign.csrk, sizeof(sign.csrk));
1338
1339 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
1340 if (csrk) {
1341 if (hcon->sec_level > BT_SECURITY_MEDIUM)
1342 csrk->type = MGMT_CSRK_LOCAL_AUTHENTICATED;
1343 else
1344 csrk->type = MGMT_CSRK_LOCAL_UNAUTHENTICATED;
1345 memcpy(csrk->val, sign.csrk, sizeof(csrk->val));
1346 }
1347 smp->responder_csrk = csrk;
1348
1349 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);
1350
1351 *keydist &= ~SMP_DIST_SIGN;
1352 }
1353
1354 /* If there are still keys to be received wait for them */
1355 if (smp->remote_key_dist & KEY_DIST_MASK) {
1356 smp_allow_key_dist(smp);
1357 return;
1358 }
1359
1360 set_bit(SMP_FLAG_COMPLETE, &smp->flags);
1361 smp_notify_keys(conn);
1362
1363 smp_chan_destroy(conn);
1364}
1365
1366static void smp_timeout(struct work_struct *work)
1367{
1368 struct smp_chan *smp = container_of(work, struct smp_chan,
1369 security_timer.work);
1370 struct l2cap_conn *conn = smp->conn;
1371
1372 bt_dev_dbg(conn->hcon->hdev, "conn %p", conn);
1373
1374 hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM);
1375}
1376
1377static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
1378{
1379 struct hci_conn *hcon = conn->hcon;
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_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
1388 if (IS_ERR(smp->tfm_cmac)) {
1389 bt_dev_err(hcon->hdev, "Unable to create CMAC crypto context");
1390 goto zfree_smp;
1391 }
1392
1393 smp->tfm_ecdh = crypto_alloc_kpp("ecdh-nist-p256", 0, 0);
1394 if (IS_ERR(smp->tfm_ecdh)) {
1395 bt_dev_err(hcon->hdev, "Unable to create ECDH crypto context");
1396 goto free_shash;
1397 }
1398
1399 smp->conn = conn;
1400 chan->data = smp;
1401
1402 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL);
1403
1404 INIT_DELAYED_WORK(&smp->security_timer, smp_timeout);
1405
1406 hci_conn_hold(hcon);
1407
1408 return smp;
1409
1410free_shash:
1411 crypto_free_shash(smp->tfm_cmac);
1412zfree_smp:
1413 kfree_sensitive(smp);
1414 return NULL;
1415}
1416
1417static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16])
1418{
1419 struct hci_conn *hcon = smp->conn->hcon;
1420 u8 *na, *nb, a[7], b[7];
1421
1422 if (hcon->out) {
1423 na = smp->prnd;
1424 nb = smp->rrnd;
1425 } else {
1426 na = smp->rrnd;
1427 nb = smp->prnd;
1428 }
1429
1430 memcpy(a, &hcon->init_addr, 6);
1431 memcpy(b, &hcon->resp_addr, 6);
1432 a[6] = hcon->init_addr_type;
1433 b[6] = hcon->resp_addr_type;
1434
1435 return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk);
1436}
1437
1438static void sc_dhkey_check(struct smp_chan *smp)
1439{
1440 struct hci_conn *hcon = smp->conn->hcon;
1441 struct smp_cmd_dhkey_check check;
1442 u8 a[7], b[7], *local_addr, *remote_addr;
1443 u8 io_cap[3], r[16];
1444
1445 memcpy(a, &hcon->init_addr, 6);
1446 memcpy(b, &hcon->resp_addr, 6);
1447 a[6] = hcon->init_addr_type;
1448 b[6] = hcon->resp_addr_type;
1449
1450 if (hcon->out) {
1451 local_addr = a;
1452 remote_addr = b;
1453 memcpy(io_cap, &smp->preq[1], 3);
1454 } else {
1455 local_addr = b;
1456 remote_addr = a;
1457 memcpy(io_cap, &smp->prsp[1], 3);
1458 }
1459
1460 memset(r, 0, sizeof(r));
1461
1462 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
1463 put_unaligned_le32(hcon->passkey_notify, r);
1464
1465 if (smp->method == REQ_OOB)
1466 memcpy(r, smp->rr, 16);
1467
1468 smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap,
1469 local_addr, remote_addr, check.e);
1470
1471 smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check);
1472}
1473
1474static u8 sc_passkey_send_confirm(struct smp_chan *smp)
1475{
1476 struct l2cap_conn *conn = smp->conn;
1477 struct hci_conn *hcon = conn->hcon;
1478 struct smp_cmd_pairing_confirm cfm;
1479 u8 r;
1480
1481 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1482 r |= 0x80;
1483
1484 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1485
1486 if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r,
1487 cfm.confirm_val))
1488 return SMP_UNSPECIFIED;
1489
1490 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
1491
1492 return 0;
1493}
1494
1495static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op)
1496{
1497 struct l2cap_conn *conn = smp->conn;
1498 struct hci_conn *hcon = conn->hcon;
1499 struct hci_dev *hdev = hcon->hdev;
1500 u8 cfm[16], r;
1501
1502 /* Ignore the PDU if we've already done 20 rounds (0 - 19) */
1503 if (smp->passkey_round >= 20)
1504 return 0;
1505
1506 switch (smp_op) {
1507 case SMP_CMD_PAIRING_RANDOM:
1508 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1509 r |= 0x80;
1510
1511 if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
1512 smp->rrnd, r, cfm))
1513 return SMP_UNSPECIFIED;
1514
1515 if (crypto_memneq(smp->pcnf, cfm, 16))
1516 return SMP_CONFIRM_FAILED;
1517
1518 smp->passkey_round++;
1519
1520 if (smp->passkey_round == 20) {
1521 /* Generate MacKey and LTK */
1522 if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk))
1523 return SMP_UNSPECIFIED;
1524 }
1525
1526 /* The round is only complete when the initiator
1527 * receives pairing random.
1528 */
1529 if (!hcon->out) {
1530 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1531 sizeof(smp->prnd), smp->prnd);
1532 if (smp->passkey_round == 20)
1533 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1534 else
1535 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1536 return 0;
1537 }
1538
1539 /* Start the next round */
1540 if (smp->passkey_round != 20)
1541 return sc_passkey_round(smp, 0);
1542
1543 /* Passkey rounds are complete - start DHKey Check */
1544 sc_dhkey_check(smp);
1545 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1546
1547 break;
1548
1549 case SMP_CMD_PAIRING_CONFIRM:
1550 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
1551 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
1552 return 0;
1553 }
1554
1555 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1556
1557 if (hcon->out) {
1558 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1559 sizeof(smp->prnd), smp->prnd);
1560 return 0;
1561 }
1562
1563 return sc_passkey_send_confirm(smp);
1564
1565 case SMP_CMD_PUBLIC_KEY:
1566 default:
1567 /* Initiating device starts the round */
1568 if (!hcon->out)
1569 return 0;
1570
1571 bt_dev_dbg(hdev, "Starting passkey round %u",
1572 smp->passkey_round + 1);
1573
1574 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1575
1576 return sc_passkey_send_confirm(smp);
1577 }
1578
1579 return 0;
1580}
1581
1582static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey)
1583{
1584 struct l2cap_conn *conn = smp->conn;
1585 struct hci_conn *hcon = conn->hcon;
1586 u8 smp_op;
1587
1588 clear_bit(SMP_FLAG_WAIT_USER, &smp->flags);
1589
1590 switch (mgmt_op) {
1591 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1592 smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED);
1593 return 0;
1594 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1595 smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED);
1596 return 0;
1597 case MGMT_OP_USER_PASSKEY_REPLY:
1598 hcon->passkey_notify = le32_to_cpu(passkey);
1599 smp->passkey_round = 0;
1600
1601 if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags))
1602 smp_op = SMP_CMD_PAIRING_CONFIRM;
1603 else
1604 smp_op = 0;
1605
1606 if (sc_passkey_round(smp, smp_op))
1607 return -EIO;
1608
1609 return 0;
1610 }
1611
1612 /* Initiator sends DHKey check first */
1613 if (hcon->out) {
1614 sc_dhkey_check(smp);
1615 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1616 } else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) {
1617 sc_dhkey_check(smp);
1618 sc_add_ltk(smp);
1619 }
1620
1621 return 0;
1622}
1623
1624int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
1625{
1626 struct l2cap_conn *conn = hcon->l2cap_data;
1627 struct l2cap_chan *chan;
1628 struct smp_chan *smp;
1629 u32 value;
1630 int err;
1631
1632 if (!conn)
1633 return -ENOTCONN;
1634
1635 bt_dev_dbg(conn->hcon->hdev, "");
1636
1637 chan = conn->smp;
1638 if (!chan)
1639 return -ENOTCONN;
1640
1641 l2cap_chan_lock(chan);
1642 if (!chan->data) {
1643 err = -ENOTCONN;
1644 goto unlock;
1645 }
1646
1647 smp = chan->data;
1648
1649 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1650 err = sc_user_reply(smp, mgmt_op, passkey);
1651 goto unlock;
1652 }
1653
1654 switch (mgmt_op) {
1655 case MGMT_OP_USER_PASSKEY_REPLY:
1656 value = le32_to_cpu(passkey);
1657 memset(smp->tk, 0, sizeof(smp->tk));
1658 bt_dev_dbg(conn->hcon->hdev, "PassKey: %u", value);
1659 put_unaligned_le32(value, smp->tk);
1660 fallthrough;
1661 case MGMT_OP_USER_CONFIRM_REPLY:
1662 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
1663 break;
1664 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1665 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1666 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1667 err = 0;
1668 goto unlock;
1669 default:
1670 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1671 err = -EOPNOTSUPP;
1672 goto unlock;
1673 }
1674
1675 err = 0;
1676
1677 /* If it is our turn to send Pairing Confirm, do so now */
1678 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) {
1679 u8 rsp = smp_confirm(smp);
1680 if (rsp)
1681 smp_failure(conn, rsp);
1682 }
1683
1684unlock:
1685 l2cap_chan_unlock(chan);
1686 return err;
1687}
1688
1689static void build_bredr_pairing_cmd(struct smp_chan *smp,
1690 struct smp_cmd_pairing *req,
1691 struct smp_cmd_pairing *rsp)
1692{
1693 struct l2cap_conn *conn = smp->conn;
1694 struct hci_dev *hdev = conn->hcon->hdev;
1695 u8 local_dist = 0, remote_dist = 0;
1696
1697 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
1698 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1699 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1700 }
1701
1702 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
1703 remote_dist |= SMP_DIST_ID_KEY;
1704
1705 if (hci_dev_test_flag(hdev, HCI_PRIVACY))
1706 local_dist |= SMP_DIST_ID_KEY;
1707
1708 if (!rsp) {
1709 memset(req, 0, sizeof(*req));
1710
1711 req->auth_req = SMP_AUTH_CT2;
1712 req->init_key_dist = local_dist;
1713 req->resp_key_dist = remote_dist;
1714 req->max_key_size = conn->hcon->enc_key_size;
1715
1716 smp->remote_key_dist = remote_dist;
1717
1718 return;
1719 }
1720
1721 memset(rsp, 0, sizeof(*rsp));
1722
1723 rsp->auth_req = SMP_AUTH_CT2;
1724 rsp->max_key_size = conn->hcon->enc_key_size;
1725 rsp->init_key_dist = req->init_key_dist & remote_dist;
1726 rsp->resp_key_dist = req->resp_key_dist & local_dist;
1727
1728 smp->remote_key_dist = rsp->init_key_dist;
1729}
1730
1731static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
1732{
1733 struct smp_cmd_pairing rsp, *req = (void *) skb->data;
1734 struct l2cap_chan *chan = conn->smp;
1735 struct hci_dev *hdev = conn->hcon->hdev;
1736 struct smp_chan *smp;
1737 u8 key_size, auth, sec_level;
1738 int ret;
1739
1740 bt_dev_dbg(hdev, "conn %p", conn);
1741
1742 if (skb->len < sizeof(*req))
1743 return SMP_INVALID_PARAMS;
1744
1745 if (conn->hcon->role != HCI_ROLE_SLAVE)
1746 return SMP_CMD_NOTSUPP;
1747
1748 if (!chan->data)
1749 smp = smp_chan_create(conn);
1750 else
1751 smp = chan->data;
1752
1753 if (!smp)
1754 return SMP_UNSPECIFIED;
1755
1756 /* We didn't start the pairing, so match remote */
1757 auth = req->auth_req & AUTH_REQ_MASK(hdev);
1758
1759 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
1760 (auth & SMP_AUTH_BONDING))
1761 return SMP_PAIRING_NOTSUPP;
1762
1763 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1764 return SMP_AUTH_REQUIREMENTS;
1765
1766 smp->preq[0] = SMP_CMD_PAIRING_REQ;
1767 memcpy(&smp->preq[1], req, sizeof(*req));
1768 skb_pull(skb, sizeof(*req));
1769
1770 /* If the remote side's OOB flag is set it means it has
1771 * successfully received our local OOB data - therefore set the
1772 * flag to indicate that local OOB is in use.
1773 */
1774 if (req->oob_flag == SMP_OOB_PRESENT && SMP_DEV(hdev)->local_oob)
1775 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1776
1777 /* SMP over BR/EDR requires special treatment */
1778 if (conn->hcon->type == ACL_LINK) {
1779 /* We must have a BR/EDR SC link */
1780 if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) &&
1781 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
1782 return SMP_CROSS_TRANSP_NOT_ALLOWED;
1783
1784 set_bit(SMP_FLAG_SC, &smp->flags);
1785
1786 build_bredr_pairing_cmd(smp, req, &rsp);
1787
1788 if (req->auth_req & SMP_AUTH_CT2)
1789 set_bit(SMP_FLAG_CT2, &smp->flags);
1790
1791 key_size = min(req->max_key_size, rsp.max_key_size);
1792 if (check_enc_key_size(conn, key_size))
1793 return SMP_ENC_KEY_SIZE;
1794
1795 /* Clear bits which are generated but not distributed */
1796 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1797
1798 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1799 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1800 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1801
1802 smp_distribute_keys(smp);
1803 return 0;
1804 }
1805
1806 build_pairing_cmd(conn, req, &rsp, auth);
1807
1808 if (rsp.auth_req & SMP_AUTH_SC) {
1809 set_bit(SMP_FLAG_SC, &smp->flags);
1810
1811 if (rsp.auth_req & SMP_AUTH_CT2)
1812 set_bit(SMP_FLAG_CT2, &smp->flags);
1813 }
1814
1815 if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
1816 sec_level = BT_SECURITY_MEDIUM;
1817 else
1818 sec_level = authreq_to_seclevel(auth);
1819
1820 if (sec_level > conn->hcon->pending_sec_level)
1821 conn->hcon->pending_sec_level = sec_level;
1822
1823 /* If we need MITM check that it can be achieved */
1824 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1825 u8 method;
1826
1827 method = get_auth_method(smp, conn->hcon->io_capability,
1828 req->io_capability);
1829 if (method == JUST_WORKS || method == JUST_CFM)
1830 return SMP_AUTH_REQUIREMENTS;
1831 }
1832
1833 key_size = min(req->max_key_size, rsp.max_key_size);
1834 if (check_enc_key_size(conn, key_size))
1835 return SMP_ENC_KEY_SIZE;
1836
1837 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1838
1839 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1840 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1841
1842 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1843
1844 clear_bit(SMP_FLAG_INITIATOR, &smp->flags);
1845
1846 /* Strictly speaking we shouldn't allow Pairing Confirm for the
1847 * SC case, however some implementations incorrectly copy RFU auth
1848 * req bits from our security request, which may create a false
1849 * positive SC enablement.
1850 */
1851 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1852
1853 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1854 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
1855 /* Clear bits which are generated but not distributed */
1856 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1857 /* Wait for Public Key from Initiating Device */
1858 return 0;
1859 }
1860
1861 /* Request setup of TK */
1862 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability);
1863 if (ret)
1864 return SMP_UNSPECIFIED;
1865
1866 return 0;
1867}
1868
1869static u8 sc_send_public_key(struct smp_chan *smp)
1870{
1871 struct hci_dev *hdev = smp->conn->hcon->hdev;
1872
1873 bt_dev_dbg(hdev, "");
1874
1875 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) {
1876 struct l2cap_chan *chan = hdev->smp_data;
1877 struct smp_dev *smp_dev;
1878
1879 if (!chan || !chan->data)
1880 return SMP_UNSPECIFIED;
1881
1882 smp_dev = chan->data;
1883
1884 memcpy(smp->local_pk, smp_dev->local_pk, 64);
1885 memcpy(smp->lr, smp_dev->local_rand, 16);
1886
1887 if (smp_dev->debug_key)
1888 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1889
1890 goto done;
1891 }
1892
1893 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
1894 bt_dev_dbg(hdev, "Using debug keys");
1895 if (set_ecdh_privkey(smp->tfm_ecdh, debug_sk))
1896 return SMP_UNSPECIFIED;
1897 memcpy(smp->local_pk, debug_pk, 64);
1898 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1899 } else {
1900 while (true) {
1901 /* Generate key pair for Secure Connections */
1902 if (generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk))
1903 return SMP_UNSPECIFIED;
1904
1905 /* This is unlikely, but we need to check that
1906 * we didn't accidentally generate a debug key.
1907 */
1908 if (crypto_memneq(smp->local_pk, debug_pk, 64))
1909 break;
1910 }
1911 }
1912
1913done:
1914 SMP_DBG("Local Public Key X: %32phN", smp->local_pk);
1915 SMP_DBG("Local Public Key Y: %32phN", smp->local_pk + 32);
1916
1917 smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk);
1918
1919 return 0;
1920}
1921
1922static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
1923{
1924 struct smp_cmd_pairing *req, *rsp = (void *) skb->data;
1925 struct l2cap_chan *chan = conn->smp;
1926 struct smp_chan *smp = chan->data;
1927 struct hci_dev *hdev = conn->hcon->hdev;
1928 u8 key_size, auth;
1929 int ret;
1930
1931 bt_dev_dbg(hdev, "conn %p", conn);
1932
1933 if (skb->len < sizeof(*rsp))
1934 return SMP_INVALID_PARAMS;
1935
1936 if (conn->hcon->role != HCI_ROLE_MASTER)
1937 return SMP_CMD_NOTSUPP;
1938
1939 skb_pull(skb, sizeof(*rsp));
1940
1941 req = (void *) &smp->preq[1];
1942
1943 key_size = min(req->max_key_size, rsp->max_key_size);
1944 if (check_enc_key_size(conn, key_size))
1945 return SMP_ENC_KEY_SIZE;
1946
1947 auth = rsp->auth_req & AUTH_REQ_MASK(hdev);
1948
1949 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1950 return SMP_AUTH_REQUIREMENTS;
1951
1952 /* If the remote side's OOB flag is set it means it has
1953 * successfully received our local OOB data - therefore set the
1954 * flag to indicate that local OOB is in use.
1955 */
1956 if (rsp->oob_flag == SMP_OOB_PRESENT && SMP_DEV(hdev)->local_oob)
1957 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1958
1959 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1960 memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
1961
1962 /* Update remote key distribution in case the remote cleared
1963 * some bits that we had enabled in our request.
1964 */
1965 smp->remote_key_dist &= rsp->resp_key_dist;
1966
1967 if ((req->auth_req & SMP_AUTH_CT2) && (auth & SMP_AUTH_CT2))
1968 set_bit(SMP_FLAG_CT2, &smp->flags);
1969
1970 /* For BR/EDR this means we're done and can start phase 3 */
1971 if (conn->hcon->type == ACL_LINK) {
1972 /* Clear bits which are generated but not distributed */
1973 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1974 smp_distribute_keys(smp);
1975 return 0;
1976 }
1977
1978 if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC))
1979 set_bit(SMP_FLAG_SC, &smp->flags);
1980 else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH)
1981 conn->hcon->pending_sec_level = BT_SECURITY_HIGH;
1982
1983 /* If we need MITM check that it can be achieved */
1984 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1985 u8 method;
1986
1987 method = get_auth_method(smp, req->io_capability,
1988 rsp->io_capability);
1989 if (method == JUST_WORKS || method == JUST_CFM)
1990 return SMP_AUTH_REQUIREMENTS;
1991 }
1992
1993 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1994
1995 /* Update remote key distribution in case the remote cleared
1996 * some bits that we had enabled in our request.
1997 */
1998 smp->remote_key_dist &= rsp->resp_key_dist;
1999
2000 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
2001 /* Clear bits which are generated but not distributed */
2002 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
2003 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
2004 return sc_send_public_key(smp);
2005 }
2006
2007 auth |= req->auth_req;
2008
2009 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability);
2010 if (ret)
2011 return SMP_UNSPECIFIED;
2012
2013 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
2014
2015 /* Can't compose response until we have been confirmed */
2016 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
2017 return smp_confirm(smp);
2018
2019 return 0;
2020}
2021
2022static u8 sc_check_confirm(struct smp_chan *smp)
2023{
2024 struct l2cap_conn *conn = smp->conn;
2025
2026 bt_dev_dbg(conn->hcon->hdev, "");
2027
2028 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2029 return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM);
2030
2031 if (conn->hcon->out) {
2032 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2033 smp->prnd);
2034 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2035 }
2036
2037 return 0;
2038}
2039
2040/* Work-around for some implementations that incorrectly copy RFU bits
2041 * from our security request and thereby create the impression that
2042 * we're doing SC when in fact the remote doesn't support it.
2043 */
2044static int fixup_sc_false_positive(struct smp_chan *smp)
2045{
2046 struct l2cap_conn *conn = smp->conn;
2047 struct hci_conn *hcon = conn->hcon;
2048 struct hci_dev *hdev = hcon->hdev;
2049 struct smp_cmd_pairing *req, *rsp;
2050 u8 auth;
2051
2052 /* The issue is only observed when we're in responder role */
2053 if (hcon->out)
2054 return SMP_UNSPECIFIED;
2055
2056 if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) {
2057 bt_dev_err(hdev, "refusing legacy fallback in SC-only mode");
2058 return SMP_UNSPECIFIED;
2059 }
2060
2061 bt_dev_err(hdev, "trying to fall back to legacy SMP");
2062
2063 req = (void *) &smp->preq[1];
2064 rsp = (void *) &smp->prsp[1];
2065
2066 /* Rebuild key dist flags which may have been cleared for SC */
2067 smp->remote_key_dist = (req->init_key_dist & rsp->resp_key_dist);
2068
2069 auth = req->auth_req & AUTH_REQ_MASK(hdev);
2070
2071 if (tk_request(conn, 0, auth, rsp->io_capability, req->io_capability)) {
2072 bt_dev_err(hdev, "failed to fall back to legacy SMP");
2073 return SMP_UNSPECIFIED;
2074 }
2075
2076 clear_bit(SMP_FLAG_SC, &smp->flags);
2077
2078 return 0;
2079}
2080
2081static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
2082{
2083 struct l2cap_chan *chan = conn->smp;
2084 struct smp_chan *smp = chan->data;
2085 struct hci_conn *hcon = conn->hcon;
2086 struct hci_dev *hdev = hcon->hdev;
2087
2088 bt_dev_dbg(hdev, "conn %p %s", conn,
2089 hcon->out ? "initiator" : "responder");
2090
2091 if (skb->len < sizeof(smp->pcnf))
2092 return SMP_INVALID_PARAMS;
2093
2094 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
2095 skb_pull(skb, sizeof(smp->pcnf));
2096
2097 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
2098 int ret;
2099
2100 /* Public Key exchange must happen before any other steps */
2101 if (test_bit(SMP_FLAG_REMOTE_PK, &smp->flags))
2102 return sc_check_confirm(smp);
2103
2104 bt_dev_err(hdev, "Unexpected SMP Pairing Confirm");
2105
2106 ret = fixup_sc_false_positive(smp);
2107 if (ret)
2108 return ret;
2109 }
2110
2111 if (conn->hcon->out) {
2112 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2113 smp->prnd);
2114 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2115 return 0;
2116 }
2117
2118 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
2119 return smp_confirm(smp);
2120
2121 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
2122
2123 return 0;
2124}
2125
2126static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
2127{
2128 struct l2cap_chan *chan = conn->smp;
2129 struct smp_chan *smp = chan->data;
2130 struct hci_conn *hcon = conn->hcon;
2131 u8 *pkax, *pkbx, *na, *nb, confirm_hint;
2132 u32 passkey;
2133 int err;
2134
2135 bt_dev_dbg(hcon->hdev, "conn %p", conn);
2136
2137 if (skb->len < sizeof(smp->rrnd))
2138 return SMP_INVALID_PARAMS;
2139
2140 memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd));
2141 skb_pull(skb, sizeof(smp->rrnd));
2142
2143 if (!test_bit(SMP_FLAG_SC, &smp->flags))
2144 return smp_random(smp);
2145
2146 if (hcon->out) {
2147 pkax = smp->local_pk;
2148 pkbx = smp->remote_pk;
2149 na = smp->prnd;
2150 nb = smp->rrnd;
2151 } else {
2152 pkax = smp->remote_pk;
2153 pkbx = smp->local_pk;
2154 na = smp->rrnd;
2155 nb = smp->prnd;
2156 }
2157
2158 if (smp->method == REQ_OOB) {
2159 if (!hcon->out)
2160 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2161 sizeof(smp->prnd), smp->prnd);
2162 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2163 goto mackey_and_ltk;
2164 }
2165
2166 /* Passkey entry has special treatment */
2167 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2168 return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM);
2169
2170 if (hcon->out) {
2171 u8 cfm[16];
2172
2173 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
2174 smp->rrnd, 0, cfm);
2175 if (err)
2176 return SMP_UNSPECIFIED;
2177
2178 if (crypto_memneq(smp->pcnf, cfm, 16))
2179 return SMP_CONFIRM_FAILED;
2180 } else {
2181 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2182 smp->prnd);
2183 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2184
2185 /* Only Just-Works pairing requires extra checks */
2186 if (smp->method != JUST_WORKS)
2187 goto mackey_and_ltk;
2188
2189 /* If there already exists long term key in local host, leave
2190 * the decision to user space since the remote device could
2191 * be legitimate or malicious.
2192 */
2193 if (hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
2194 hcon->role)) {
2195 /* Set passkey to 0. The value can be any number since
2196 * it'll be ignored anyway.
2197 */
2198 passkey = 0;
2199 confirm_hint = 1;
2200 goto confirm;
2201 }
2202 }
2203
2204mackey_and_ltk:
2205 /* Generate MacKey and LTK */
2206 err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk);
2207 if (err)
2208 return SMP_UNSPECIFIED;
2209
2210 if (smp->method == REQ_OOB) {
2211 if (hcon->out) {
2212 sc_dhkey_check(smp);
2213 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2214 }
2215 return 0;
2216 }
2217
2218 err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);
2219 if (err)
2220 return SMP_UNSPECIFIED;
2221
2222 confirm_hint = 0;
2223
2224confirm:
2225 if (smp->method == JUST_WORKS)
2226 confirm_hint = 1;
2227
2228 err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type,
2229 hcon->dst_type, passkey, confirm_hint);
2230 if (err)
2231 return SMP_UNSPECIFIED;
2232
2233 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2234
2235 return 0;
2236}
2237
2238static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
2239{
2240 struct smp_ltk *key;
2241 struct hci_conn *hcon = conn->hcon;
2242
2243 key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role);
2244 if (!key)
2245 return false;
2246
2247 if (smp_ltk_sec_level(key) < sec_level)
2248 return false;
2249
2250 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
2251 return true;
2252
2253 hci_le_start_enc(hcon, key->ediv, key->rand, key->val, key->enc_size);
2254 hcon->enc_key_size = key->enc_size;
2255
2256 /* We never store STKs for initiator role, so clear this flag */
2257 clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
2258
2259 return true;
2260}
2261
2262bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level,
2263 enum smp_key_pref key_pref)
2264{
2265 if (sec_level == BT_SECURITY_LOW)
2266 return true;
2267
2268 /* If we're encrypted with an STK but the caller prefers using
2269 * LTK claim insufficient security. This way we allow the
2270 * connection to be re-encrypted with an LTK, even if the LTK
2271 * provides the same level of security. Only exception is if we
2272 * don't have an LTK (e.g. because of key distribution bits).
2273 */
2274 if (key_pref == SMP_USE_LTK &&
2275 test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) &&
2276 hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role))
2277 return false;
2278
2279 if (hcon->sec_level >= sec_level)
2280 return true;
2281
2282 return false;
2283}
2284
2285static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
2286{
2287 struct smp_cmd_security_req *rp = (void *) skb->data;
2288 struct smp_cmd_pairing cp;
2289 struct hci_conn *hcon = conn->hcon;
2290 struct hci_dev *hdev = hcon->hdev;
2291 struct smp_chan *smp;
2292 u8 sec_level, auth;
2293
2294 bt_dev_dbg(hdev, "conn %p", conn);
2295
2296 if (skb->len < sizeof(*rp))
2297 return SMP_INVALID_PARAMS;
2298
2299 if (hcon->role != HCI_ROLE_MASTER)
2300 return SMP_CMD_NOTSUPP;
2301
2302 auth = rp->auth_req & AUTH_REQ_MASK(hdev);
2303
2304 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
2305 return SMP_AUTH_REQUIREMENTS;
2306
2307 if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
2308 sec_level = BT_SECURITY_MEDIUM;
2309 else
2310 sec_level = authreq_to_seclevel(auth);
2311
2312 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) {
2313 /* If link is already encrypted with sufficient security we
2314 * still need refresh encryption as per Core Spec 5.0 Vol 3,
2315 * Part H 2.4.6
2316 */
2317 smp_ltk_encrypt(conn, hcon->sec_level);
2318 return 0;
2319 }
2320
2321 if (sec_level > hcon->pending_sec_level)
2322 hcon->pending_sec_level = sec_level;
2323
2324 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2325 return 0;
2326
2327 smp = smp_chan_create(conn);
2328 if (!smp)
2329 return SMP_UNSPECIFIED;
2330
2331 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
2332 (auth & SMP_AUTH_BONDING))
2333 return SMP_PAIRING_NOTSUPP;
2334
2335 skb_pull(skb, sizeof(*rp));
2336
2337 memset(&cp, 0, sizeof(cp));
2338 build_pairing_cmd(conn, &cp, NULL, auth);
2339
2340 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2341 memcpy(&smp->preq[1], &cp, sizeof(cp));
2342
2343 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2344 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2345
2346 return 0;
2347}
2348
2349int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
2350{
2351 struct l2cap_conn *conn = hcon->l2cap_data;
2352 struct l2cap_chan *chan;
2353 struct smp_chan *smp;
2354 __u8 authreq;
2355 int ret;
2356
2357 bt_dev_dbg(hcon->hdev, "conn %p hcon %p level 0x%2.2x", conn, hcon,
2358 sec_level);
2359
2360 /* This may be NULL if there's an unexpected disconnection */
2361 if (!conn)
2362 return 1;
2363
2364 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED))
2365 return 1;
2366
2367 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
2368 return 1;
2369
2370 if (sec_level > hcon->pending_sec_level)
2371 hcon->pending_sec_level = sec_level;
2372
2373 if (hcon->role == HCI_ROLE_MASTER)
2374 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2375 return 0;
2376
2377 chan = conn->smp;
2378 if (!chan) {
2379 bt_dev_err(hcon->hdev, "security requested but not available");
2380 return 1;
2381 }
2382
2383 l2cap_chan_lock(chan);
2384
2385 /* If SMP is already in progress ignore this request */
2386 if (chan->data) {
2387 ret = 0;
2388 goto unlock;
2389 }
2390
2391 smp = smp_chan_create(conn);
2392 if (!smp) {
2393 ret = 1;
2394 goto unlock;
2395 }
2396
2397 authreq = seclevel_to_authreq(sec_level);
2398
2399 if (hci_dev_test_flag(hcon->hdev, HCI_SC_ENABLED)) {
2400 authreq |= SMP_AUTH_SC;
2401 if (hci_dev_test_flag(hcon->hdev, HCI_SSP_ENABLED))
2402 authreq |= SMP_AUTH_CT2;
2403 }
2404
2405 /* Don't attempt to set MITM if setting is overridden by debugfs
2406 * Needed to pass certification test SM/MAS/PKE/BV-01-C
2407 */
2408 if (!hci_dev_test_flag(hcon->hdev, HCI_FORCE_NO_MITM)) {
2409 /* Require MITM if IO Capability allows or the security level
2410 * requires it.
2411 */
2412 if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT ||
2413 hcon->pending_sec_level > BT_SECURITY_MEDIUM)
2414 authreq |= SMP_AUTH_MITM;
2415 }
2416
2417 if (hcon->role == HCI_ROLE_MASTER) {
2418 struct smp_cmd_pairing cp;
2419
2420 build_pairing_cmd(conn, &cp, NULL, authreq);
2421 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2422 memcpy(&smp->preq[1], &cp, sizeof(cp));
2423
2424 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2425 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2426 } else {
2427 struct smp_cmd_security_req cp;
2428 cp.auth_req = authreq;
2429 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
2430 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ);
2431 }
2432
2433 set_bit(SMP_FLAG_INITIATOR, &smp->flags);
2434 ret = 0;
2435
2436unlock:
2437 l2cap_chan_unlock(chan);
2438 return ret;
2439}
2440
2441int smp_cancel_and_remove_pairing(struct hci_dev *hdev, bdaddr_t *bdaddr,
2442 u8 addr_type)
2443{
2444 struct hci_conn *hcon;
2445 struct l2cap_conn *conn;
2446 struct l2cap_chan *chan;
2447 struct smp_chan *smp;
2448 int err;
2449
2450 err = hci_remove_ltk(hdev, bdaddr, addr_type);
2451 hci_remove_irk(hdev, bdaddr, addr_type);
2452
2453 hcon = hci_conn_hash_lookup_le(hdev, bdaddr, addr_type);
2454 if (!hcon)
2455 goto done;
2456
2457 conn = hcon->l2cap_data;
2458 if (!conn)
2459 goto done;
2460
2461 chan = conn->smp;
2462 if (!chan)
2463 goto done;
2464
2465 l2cap_chan_lock(chan);
2466
2467 smp = chan->data;
2468 if (smp) {
2469 /* Set keys to NULL to make sure smp_failure() does not try to
2470 * remove and free already invalidated rcu list entries. */
2471 smp->ltk = NULL;
2472 smp->responder_ltk = NULL;
2473 smp->remote_irk = NULL;
2474
2475 if (test_bit(SMP_FLAG_COMPLETE, &smp->flags))
2476 smp_failure(conn, 0);
2477 else
2478 smp_failure(conn, SMP_UNSPECIFIED);
2479 err = 0;
2480 }
2481
2482 l2cap_chan_unlock(chan);
2483
2484done:
2485 return err;
2486}
2487
2488static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb)
2489{
2490 struct smp_cmd_encrypt_info *rp = (void *) skb->data;
2491 struct l2cap_chan *chan = conn->smp;
2492 struct smp_chan *smp = chan->data;
2493
2494 bt_dev_dbg(conn->hcon->hdev, "conn %p", conn);
2495
2496 if (skb->len < sizeof(*rp))
2497 return SMP_INVALID_PARAMS;
2498
2499 /* Pairing is aborted if any blocked keys are distributed */
2500 if (hci_is_blocked_key(conn->hcon->hdev, HCI_BLOCKED_KEY_TYPE_LTK,
2501 rp->ltk)) {
2502 bt_dev_warn_ratelimited(conn->hcon->hdev,
2503 "LTK blocked for %pMR",
2504 &conn->hcon->dst);
2505 return SMP_INVALID_PARAMS;
2506 }
2507
2508 SMP_ALLOW_CMD(smp, SMP_CMD_INITIATOR_IDENT);
2509
2510 skb_pull(skb, sizeof(*rp));
2511
2512 memcpy(smp->tk, rp->ltk, sizeof(smp->tk));
2513
2514 return 0;
2515}
2516
2517static int smp_cmd_initiator_ident(struct l2cap_conn *conn, struct sk_buff *skb)
2518{
2519 struct smp_cmd_initiator_ident *rp = (void *)skb->data;
2520 struct l2cap_chan *chan = conn->smp;
2521 struct smp_chan *smp = chan->data;
2522 struct hci_dev *hdev = conn->hcon->hdev;
2523 struct hci_conn *hcon = conn->hcon;
2524 struct smp_ltk *ltk;
2525 u8 authenticated;
2526
2527 bt_dev_dbg(hdev, "conn %p", conn);
2528
2529 if (skb->len < sizeof(*rp))
2530 return SMP_INVALID_PARAMS;
2531
2532 /* Mark the information as received */
2533 smp->remote_key_dist &= ~SMP_DIST_ENC_KEY;
2534
2535 if (smp->remote_key_dist & SMP_DIST_ID_KEY)
2536 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
2537 else if (smp->remote_key_dist & SMP_DIST_SIGN)
2538 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2539
2540 skb_pull(skb, sizeof(*rp));
2541
2542 authenticated = (hcon->sec_level == BT_SECURITY_HIGH);
2543 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK,
2544 authenticated, smp->tk, smp->enc_key_size,
2545 rp->ediv, rp->rand);
2546 smp->ltk = ltk;
2547 if (!(smp->remote_key_dist & KEY_DIST_MASK))
2548 smp_distribute_keys(smp);
2549
2550 return 0;
2551}
2552
2553static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb)
2554{
2555 struct smp_cmd_ident_info *info = (void *) skb->data;
2556 struct l2cap_chan *chan = conn->smp;
2557 struct smp_chan *smp = chan->data;
2558
2559 bt_dev_dbg(conn->hcon->hdev, "");
2560
2561 if (skb->len < sizeof(*info))
2562 return SMP_INVALID_PARAMS;
2563
2564 /* Pairing is aborted if any blocked keys are distributed */
2565 if (hci_is_blocked_key(conn->hcon->hdev, HCI_BLOCKED_KEY_TYPE_IRK,
2566 info->irk)) {
2567 bt_dev_warn_ratelimited(conn->hcon->hdev,
2568 "Identity key blocked for %pMR",
2569 &conn->hcon->dst);
2570 return SMP_INVALID_PARAMS;
2571 }
2572
2573 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO);
2574
2575 skb_pull(skb, sizeof(*info));
2576
2577 memcpy(smp->irk, info->irk, 16);
2578
2579 return 0;
2580}
2581
2582static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,
2583 struct sk_buff *skb)
2584{
2585 struct smp_cmd_ident_addr_info *info = (void *) skb->data;
2586 struct l2cap_chan *chan = conn->smp;
2587 struct smp_chan *smp = chan->data;
2588 struct hci_conn *hcon = conn->hcon;
2589 bdaddr_t rpa;
2590
2591 bt_dev_dbg(hcon->hdev, "");
2592
2593 if (skb->len < sizeof(*info))
2594 return SMP_INVALID_PARAMS;
2595
2596 /* Mark the information as received */
2597 smp->remote_key_dist &= ~SMP_DIST_ID_KEY;
2598
2599 if (smp->remote_key_dist & SMP_DIST_SIGN)
2600 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2601
2602 skb_pull(skb, sizeof(*info));
2603
2604 /* Strictly speaking the Core Specification (4.1) allows sending
2605 * an empty address which would force us to rely on just the IRK
2606 * as "identity information". However, since such
2607 * implementations are not known of and in order to not over
2608 * complicate our implementation, simply pretend that we never
2609 * received an IRK for such a device.
2610 *
2611 * The Identity Address must also be a Static Random or Public
2612 * Address, which hci_is_identity_address() checks for.
2613 */
2614 if (!bacmp(&info->bdaddr, BDADDR_ANY) ||
2615 !hci_is_identity_address(&info->bdaddr, info->addr_type)) {
2616 bt_dev_err(hcon->hdev, "ignoring IRK with no identity address");
2617 goto distribute;
2618 }
2619
2620 /* Drop IRK if peer is using identity address during pairing but is
2621 * providing different address as identity information.
2622 *
2623 * Microsoft Surface Precision Mouse is known to have this bug.
2624 */
2625 if (hci_is_identity_address(&hcon->dst, hcon->dst_type) &&
2626 (bacmp(&info->bdaddr, &hcon->dst) ||
2627 info->addr_type != hcon->dst_type)) {
2628 bt_dev_err(hcon->hdev,
2629 "ignoring IRK with invalid identity address");
2630 goto distribute;
2631 }
2632
2633 bacpy(&smp->id_addr, &info->bdaddr);
2634 smp->id_addr_type = info->addr_type;
2635
2636 if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type))
2637 bacpy(&rpa, &hcon->dst);
2638 else
2639 bacpy(&rpa, BDADDR_ANY);
2640
2641 smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr,
2642 smp->id_addr_type, smp->irk, &rpa);
2643
2644distribute:
2645 if (!(smp->remote_key_dist & KEY_DIST_MASK))
2646 smp_distribute_keys(smp);
2647
2648 return 0;
2649}
2650
2651static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb)
2652{
2653 struct smp_cmd_sign_info *rp = (void *) skb->data;
2654 struct l2cap_chan *chan = conn->smp;
2655 struct smp_chan *smp = chan->data;
2656 struct smp_csrk *csrk;
2657
2658 bt_dev_dbg(conn->hcon->hdev, "conn %p", conn);
2659
2660 if (skb->len < sizeof(*rp))
2661 return SMP_INVALID_PARAMS;
2662
2663 /* Mark the information as received */
2664 smp->remote_key_dist &= ~SMP_DIST_SIGN;
2665
2666 skb_pull(skb, sizeof(*rp));
2667
2668 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
2669 if (csrk) {
2670 if (conn->hcon->sec_level > BT_SECURITY_MEDIUM)
2671 csrk->type = MGMT_CSRK_REMOTE_AUTHENTICATED;
2672 else
2673 csrk->type = MGMT_CSRK_REMOTE_UNAUTHENTICATED;
2674 memcpy(csrk->val, rp->csrk, sizeof(csrk->val));
2675 }
2676 smp->csrk = csrk;
2677 smp_distribute_keys(smp);
2678
2679 return 0;
2680}
2681
2682static u8 sc_select_method(struct smp_chan *smp)
2683{
2684 struct l2cap_conn *conn = smp->conn;
2685 struct hci_conn *hcon = conn->hcon;
2686 struct smp_cmd_pairing *local, *remote;
2687 u8 local_mitm, remote_mitm, local_io, remote_io, method;
2688
2689 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags) ||
2690 test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags))
2691 return REQ_OOB;
2692
2693 /* The preq/prsp contain the raw Pairing Request/Response PDUs
2694 * which are needed as inputs to some crypto functions. To get
2695 * the "struct smp_cmd_pairing" from them we need to skip the
2696 * first byte which contains the opcode.
2697 */
2698 if (hcon->out) {
2699 local = (void *) &smp->preq[1];
2700 remote = (void *) &smp->prsp[1];
2701 } else {
2702 local = (void *) &smp->prsp[1];
2703 remote = (void *) &smp->preq[1];
2704 }
2705
2706 local_io = local->io_capability;
2707 remote_io = remote->io_capability;
2708
2709 local_mitm = (local->auth_req & SMP_AUTH_MITM);
2710 remote_mitm = (remote->auth_req & SMP_AUTH_MITM);
2711
2712 /* If either side wants MITM, look up the method from the table,
2713 * otherwise use JUST WORKS.
2714 */
2715 if (local_mitm || remote_mitm)
2716 method = get_auth_method(smp, local_io, remote_io);
2717 else
2718 method = JUST_WORKS;
2719
2720 /* Don't confirm locally initiated pairing attempts */
2721 if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags))
2722 method = JUST_WORKS;
2723
2724 return method;
2725}
2726
2727static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb)
2728{
2729 struct smp_cmd_public_key *key = (void *) skb->data;
2730 struct hci_conn *hcon = conn->hcon;
2731 struct l2cap_chan *chan = conn->smp;
2732 struct smp_chan *smp = chan->data;
2733 struct hci_dev *hdev = hcon->hdev;
2734 struct crypto_kpp *tfm_ecdh;
2735 struct smp_cmd_pairing_confirm cfm;
2736 int err;
2737
2738 bt_dev_dbg(hdev, "conn %p", conn);
2739
2740 if (skb->len < sizeof(*key))
2741 return SMP_INVALID_PARAMS;
2742
2743 /* Check if remote and local public keys are the same and debug key is
2744 * not in use.
2745 */
2746 if (!test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags) &&
2747 !crypto_memneq(key, smp->local_pk, 64)) {
2748 bt_dev_err(hdev, "Remote and local public keys are identical");
2749 return SMP_UNSPECIFIED;
2750 }
2751
2752 memcpy(smp->remote_pk, key, 64);
2753
2754 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags)) {
2755 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk,
2756 smp->rr, 0, cfm.confirm_val);
2757 if (err)
2758 return SMP_UNSPECIFIED;
2759
2760 if (crypto_memneq(cfm.confirm_val, smp->pcnf, 16))
2761 return SMP_CONFIRM_FAILED;
2762 }
2763
2764 /* Non-initiating device sends its public key after receiving
2765 * the key from the initiating device.
2766 */
2767 if (!hcon->out) {
2768 err = sc_send_public_key(smp);
2769 if (err)
2770 return err;
2771 }
2772
2773 SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk);
2774 SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32);
2775
2776 /* Compute the shared secret on the same crypto tfm on which the private
2777 * key was set/generated.
2778 */
2779 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) {
2780 struct l2cap_chan *hchan = hdev->smp_data;
2781 struct smp_dev *smp_dev;
2782
2783 if (!hchan || !hchan->data)
2784 return SMP_UNSPECIFIED;
2785
2786 smp_dev = hchan->data;
2787
2788 tfm_ecdh = smp_dev->tfm_ecdh;
2789 } else {
2790 tfm_ecdh = smp->tfm_ecdh;
2791 }
2792
2793 if (compute_ecdh_secret(tfm_ecdh, smp->remote_pk, smp->dhkey))
2794 return SMP_UNSPECIFIED;
2795
2796 SMP_DBG("DHKey %32phN", smp->dhkey);
2797
2798 set_bit(SMP_FLAG_REMOTE_PK, &smp->flags);
2799
2800 smp->method = sc_select_method(smp);
2801
2802 bt_dev_dbg(hdev, "selected method 0x%02x", smp->method);
2803
2804 /* JUST_WORKS and JUST_CFM result in an unauthenticated key */
2805 if (smp->method == JUST_WORKS || smp->method == JUST_CFM)
2806 hcon->pending_sec_level = BT_SECURITY_MEDIUM;
2807 else
2808 hcon->pending_sec_level = BT_SECURITY_FIPS;
2809
2810 if (!crypto_memneq(debug_pk, smp->remote_pk, 64))
2811 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
2812
2813 if (smp->method == DSP_PASSKEY) {
2814 get_random_bytes(&hcon->passkey_notify,
2815 sizeof(hcon->passkey_notify));
2816 hcon->passkey_notify %= 1000000;
2817 hcon->passkey_entered = 0;
2818 smp->passkey_round = 0;
2819 if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type,
2820 hcon->dst_type,
2821 hcon->passkey_notify,
2822 hcon->passkey_entered))
2823 return SMP_UNSPECIFIED;
2824 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2825 return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY);
2826 }
2827
2828 if (smp->method == REQ_OOB) {
2829 if (hcon->out)
2830 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2831 sizeof(smp->prnd), smp->prnd);
2832
2833 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2834
2835 return 0;
2836 }
2837
2838 if (hcon->out)
2839 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2840
2841 if (smp->method == REQ_PASSKEY) {
2842 if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type,
2843 hcon->dst_type))
2844 return SMP_UNSPECIFIED;
2845 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2846 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2847 return 0;
2848 }
2849
2850 /* The Initiating device waits for the non-initiating device to
2851 * send the confirm value.
2852 */
2853 if (conn->hcon->out)
2854 return 0;
2855
2856 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd,
2857 0, cfm.confirm_val);
2858 if (err)
2859 return SMP_UNSPECIFIED;
2860
2861 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
2862 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2863
2864 return 0;
2865}
2866
2867static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb)
2868{
2869 struct smp_cmd_dhkey_check *check = (void *) skb->data;
2870 struct l2cap_chan *chan = conn->smp;
2871 struct hci_conn *hcon = conn->hcon;
2872 struct smp_chan *smp = chan->data;
2873 u8 a[7], b[7], *local_addr, *remote_addr;
2874 u8 io_cap[3], r[16], e[16];
2875 int err;
2876
2877 bt_dev_dbg(hcon->hdev, "conn %p", conn);
2878
2879 if (skb->len < sizeof(*check))
2880 return SMP_INVALID_PARAMS;
2881
2882 memcpy(a, &hcon->init_addr, 6);
2883 memcpy(b, &hcon->resp_addr, 6);
2884 a[6] = hcon->init_addr_type;
2885 b[6] = hcon->resp_addr_type;
2886
2887 if (hcon->out) {
2888 local_addr = a;
2889 remote_addr = b;
2890 memcpy(io_cap, &smp->prsp[1], 3);
2891 } else {
2892 local_addr = b;
2893 remote_addr = a;
2894 memcpy(io_cap, &smp->preq[1], 3);
2895 }
2896
2897 memset(r, 0, sizeof(r));
2898
2899 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2900 put_unaligned_le32(hcon->passkey_notify, r);
2901 else if (smp->method == REQ_OOB)
2902 memcpy(r, smp->lr, 16);
2903
2904 err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r,
2905 io_cap, remote_addr, local_addr, e);
2906 if (err)
2907 return SMP_UNSPECIFIED;
2908
2909 if (crypto_memneq(check->e, e, 16))
2910 return SMP_DHKEY_CHECK_FAILED;
2911
2912 if (!hcon->out) {
2913 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
2914 set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags);
2915 return 0;
2916 }
2917
2918 /* Responder sends DHKey check as response to initiator */
2919 sc_dhkey_check(smp);
2920 }
2921
2922 sc_add_ltk(smp);
2923
2924 if (hcon->out) {
2925 hci_le_start_enc(hcon, 0, 0, smp->tk, smp->enc_key_size);
2926 hcon->enc_key_size = smp->enc_key_size;
2927 }
2928
2929 return 0;
2930}
2931
2932static int smp_cmd_keypress_notify(struct l2cap_conn *conn,
2933 struct sk_buff *skb)
2934{
2935 struct smp_cmd_keypress_notify *kp = (void *) skb->data;
2936
2937 bt_dev_dbg(conn->hcon->hdev, "value 0x%02x", kp->value);
2938
2939 return 0;
2940}
2941
2942static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb)
2943{
2944 struct l2cap_conn *conn = chan->conn;
2945 struct hci_conn *hcon = conn->hcon;
2946 struct smp_chan *smp;
2947 __u8 code, reason;
2948 int err = 0;
2949
2950 if (skb->len < 1)
2951 return -EILSEQ;
2952
2953 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) {
2954 reason = SMP_PAIRING_NOTSUPP;
2955 goto done;
2956 }
2957
2958 code = skb->data[0];
2959 skb_pull(skb, sizeof(code));
2960
2961 smp = chan->data;
2962
2963 if (code > SMP_CMD_MAX)
2964 goto drop;
2965
2966 if (smp && !test_and_clear_bit(code, &smp->allow_cmd))
2967 goto drop;
2968
2969 /* If we don't have a context the only allowed commands are
2970 * pairing request and security request.
2971 */
2972 if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ)
2973 goto drop;
2974
2975 switch (code) {
2976 case SMP_CMD_PAIRING_REQ:
2977 reason = smp_cmd_pairing_req(conn, skb);
2978 break;
2979
2980 case SMP_CMD_PAIRING_FAIL:
2981 smp_failure(conn, 0);
2982 err = -EPERM;
2983 break;
2984
2985 case SMP_CMD_PAIRING_RSP:
2986 reason = smp_cmd_pairing_rsp(conn, skb);
2987 break;
2988
2989 case SMP_CMD_SECURITY_REQ:
2990 reason = smp_cmd_security_req(conn, skb);
2991 break;
2992
2993 case SMP_CMD_PAIRING_CONFIRM:
2994 reason = smp_cmd_pairing_confirm(conn, skb);
2995 break;
2996
2997 case SMP_CMD_PAIRING_RANDOM:
2998 reason = smp_cmd_pairing_random(conn, skb);
2999 break;
3000
3001 case SMP_CMD_ENCRYPT_INFO:
3002 reason = smp_cmd_encrypt_info(conn, skb);
3003 break;
3004
3005 case SMP_CMD_INITIATOR_IDENT:
3006 reason = smp_cmd_initiator_ident(conn, skb);
3007 break;
3008
3009 case SMP_CMD_IDENT_INFO:
3010 reason = smp_cmd_ident_info(conn, skb);
3011 break;
3012
3013 case SMP_CMD_IDENT_ADDR_INFO:
3014 reason = smp_cmd_ident_addr_info(conn, skb);
3015 break;
3016
3017 case SMP_CMD_SIGN_INFO:
3018 reason = smp_cmd_sign_info(conn, skb);
3019 break;
3020
3021 case SMP_CMD_PUBLIC_KEY:
3022 reason = smp_cmd_public_key(conn, skb);
3023 break;
3024
3025 case SMP_CMD_DHKEY_CHECK:
3026 reason = smp_cmd_dhkey_check(conn, skb);
3027 break;
3028
3029 case SMP_CMD_KEYPRESS_NOTIFY:
3030 reason = smp_cmd_keypress_notify(conn, skb);
3031 break;
3032
3033 default:
3034 bt_dev_dbg(hcon->hdev, "Unknown command code 0x%2.2x", code);
3035 reason = SMP_CMD_NOTSUPP;
3036 goto done;
3037 }
3038
3039done:
3040 if (!err) {
3041 if (reason)
3042 smp_failure(conn, reason);
3043 kfree_skb(skb);
3044 }
3045
3046 return err;
3047
3048drop:
3049 bt_dev_err(hcon->hdev, "unexpected SMP command 0x%02x from %pMR",
3050 code, &hcon->dst);
3051 kfree_skb(skb);
3052 return 0;
3053}
3054
3055static void smp_teardown_cb(struct l2cap_chan *chan, int err)
3056{
3057 struct l2cap_conn *conn = chan->conn;
3058
3059 bt_dev_dbg(conn->hcon->hdev, "chan %p", chan);
3060
3061 if (chan->data)
3062 smp_chan_destroy(conn);
3063
3064 conn->smp = NULL;
3065 l2cap_chan_put(chan);
3066}
3067
3068static void bredr_pairing(struct l2cap_chan *chan)
3069{
3070 struct l2cap_conn *conn = chan->conn;
3071 struct hci_conn *hcon = conn->hcon;
3072 struct hci_dev *hdev = hcon->hdev;
3073 struct smp_cmd_pairing req;
3074 struct smp_chan *smp;
3075
3076 bt_dev_dbg(hdev, "chan %p", chan);
3077
3078 /* Only new pairings are interesting */
3079 if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags))
3080 return;
3081
3082 /* Don't bother if we're not encrypted */
3083 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
3084 return;
3085
3086 /* Only initiator may initiate SMP over BR/EDR */
3087 if (hcon->role != HCI_ROLE_MASTER)
3088 return;
3089
3090 /* Secure Connections support must be enabled */
3091 if (!hci_dev_test_flag(hdev, HCI_SC_ENABLED))
3092 return;
3093
3094 /* BR/EDR must use Secure Connections for SMP */
3095 if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) &&
3096 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3097 return;
3098
3099 /* If our LE support is not enabled don't do anything */
3100 if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED))
3101 return;
3102
3103 /* Don't bother if remote LE support is not enabled */
3104 if (!lmp_host_le_capable(hcon))
3105 return;
3106
3107 /* Remote must support SMP fixed chan for BR/EDR */
3108 if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR))
3109 return;
3110
3111 /* Don't bother if SMP is already ongoing */
3112 if (chan->data)
3113 return;
3114
3115 smp = smp_chan_create(conn);
3116 if (!smp) {
3117 bt_dev_err(hdev, "unable to create SMP context for BR/EDR");
3118 return;
3119 }
3120
3121 set_bit(SMP_FLAG_SC, &smp->flags);
3122
3123 bt_dev_dbg(hdev, "starting SMP over BR/EDR");
3124
3125 /* Prepare and send the BR/EDR SMP Pairing Request */
3126 build_bredr_pairing_cmd(smp, &req, NULL);
3127
3128 smp->preq[0] = SMP_CMD_PAIRING_REQ;
3129 memcpy(&smp->preq[1], &req, sizeof(req));
3130
3131 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req);
3132 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
3133}
3134
3135static void smp_resume_cb(struct l2cap_chan *chan)
3136{
3137 struct smp_chan *smp = chan->data;
3138 struct l2cap_conn *conn = chan->conn;
3139 struct hci_conn *hcon = conn->hcon;
3140
3141 bt_dev_dbg(hcon->hdev, "chan %p", chan);
3142
3143 if (hcon->type == ACL_LINK) {
3144 bredr_pairing(chan);
3145 return;
3146 }
3147
3148 if (!smp)
3149 return;
3150
3151 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
3152 return;
3153
3154 cancel_delayed_work(&smp->security_timer);
3155
3156 smp_distribute_keys(smp);
3157}
3158
3159static void smp_ready_cb(struct l2cap_chan *chan)
3160{
3161 struct l2cap_conn *conn = chan->conn;
3162 struct hci_conn *hcon = conn->hcon;
3163
3164 bt_dev_dbg(hcon->hdev, "chan %p", chan);
3165
3166 /* No need to call l2cap_chan_hold() here since we already own
3167 * the reference taken in smp_new_conn_cb(). This is just the
3168 * first time that we tie it to a specific pointer. The code in
3169 * l2cap_core.c ensures that there's no risk this function wont
3170 * get called if smp_new_conn_cb was previously called.
3171 */
3172 conn->smp = chan;
3173
3174 if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
3175 bredr_pairing(chan);
3176}
3177
3178static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
3179{
3180 int err;
3181
3182 bt_dev_dbg(chan->conn->hcon->hdev, "chan %p", chan);
3183
3184 err = smp_sig_channel(chan, skb);
3185 if (err) {
3186 struct smp_chan *smp = chan->data;
3187
3188 if (smp)
3189 cancel_delayed_work_sync(&smp->security_timer);
3190
3191 hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE);
3192 }
3193
3194 return err;
3195}
3196
3197static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan,
3198 unsigned long hdr_len,
3199 unsigned long len, int nb)
3200{
3201 struct sk_buff *skb;
3202
3203 skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL);
3204 if (!skb)
3205 return ERR_PTR(-ENOMEM);
3206
3207 skb->priority = HCI_PRIO_MAX;
3208 bt_cb(skb)->l2cap.chan = chan;
3209
3210 return skb;
3211}
3212
3213static const struct l2cap_ops smp_chan_ops = {
3214 .name = "Security Manager",
3215 .ready = smp_ready_cb,
3216 .recv = smp_recv_cb,
3217 .alloc_skb = smp_alloc_skb_cb,
3218 .teardown = smp_teardown_cb,
3219 .resume = smp_resume_cb,
3220
3221 .new_connection = l2cap_chan_no_new_connection,
3222 .state_change = l2cap_chan_no_state_change,
3223 .close = l2cap_chan_no_close,
3224 .defer = l2cap_chan_no_defer,
3225 .suspend = l2cap_chan_no_suspend,
3226 .set_shutdown = l2cap_chan_no_set_shutdown,
3227 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
3228};
3229
3230static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan)
3231{
3232 struct l2cap_chan *chan;
3233
3234 BT_DBG("pchan %p", pchan);
3235
3236 chan = l2cap_chan_create();
3237 if (!chan)
3238 return NULL;
3239
3240 chan->chan_type = pchan->chan_type;
3241 chan->ops = &smp_chan_ops;
3242 chan->scid = pchan->scid;
3243 chan->dcid = chan->scid;
3244 chan->imtu = pchan->imtu;
3245 chan->omtu = pchan->omtu;
3246 chan->mode = pchan->mode;
3247
3248 /* Other L2CAP channels may request SMP routines in order to
3249 * change the security level. This means that the SMP channel
3250 * lock must be considered in its own category to avoid lockdep
3251 * warnings.
3252 */
3253 atomic_set(&chan->nesting, L2CAP_NESTING_SMP);
3254
3255 BT_DBG("created chan %p", chan);
3256
3257 return chan;
3258}
3259
3260static const struct l2cap_ops smp_root_chan_ops = {
3261 .name = "Security Manager Root",
3262 .new_connection = smp_new_conn_cb,
3263
3264 /* None of these are implemented for the root channel */
3265 .close = l2cap_chan_no_close,
3266 .alloc_skb = l2cap_chan_no_alloc_skb,
3267 .recv = l2cap_chan_no_recv,
3268 .state_change = l2cap_chan_no_state_change,
3269 .teardown = l2cap_chan_no_teardown,
3270 .ready = l2cap_chan_no_ready,
3271 .defer = l2cap_chan_no_defer,
3272 .suspend = l2cap_chan_no_suspend,
3273 .resume = l2cap_chan_no_resume,
3274 .set_shutdown = l2cap_chan_no_set_shutdown,
3275 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
3276};
3277
3278static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid)
3279{
3280 struct l2cap_chan *chan;
3281 struct smp_dev *smp;
3282 struct crypto_shash *tfm_cmac;
3283 struct crypto_kpp *tfm_ecdh;
3284
3285 if (cid == L2CAP_CID_SMP_BREDR) {
3286 smp = NULL;
3287 goto create_chan;
3288 }
3289
3290 smp = kzalloc(sizeof(*smp), GFP_KERNEL);
3291 if (!smp)
3292 return ERR_PTR(-ENOMEM);
3293
3294 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
3295 if (IS_ERR(tfm_cmac)) {
3296 bt_dev_err(hdev, "Unable to create CMAC crypto context");
3297 kfree_sensitive(smp);
3298 return ERR_CAST(tfm_cmac);
3299 }
3300
3301 tfm_ecdh = crypto_alloc_kpp("ecdh-nist-p256", 0, 0);
3302 if (IS_ERR(tfm_ecdh)) {
3303 bt_dev_err(hdev, "Unable to create ECDH crypto context");
3304 crypto_free_shash(tfm_cmac);
3305 kfree_sensitive(smp);
3306 return ERR_CAST(tfm_ecdh);
3307 }
3308
3309 smp->local_oob = false;
3310 smp->tfm_cmac = tfm_cmac;
3311 smp->tfm_ecdh = tfm_ecdh;
3312
3313create_chan:
3314 chan = l2cap_chan_create();
3315 if (!chan) {
3316 if (smp) {
3317 crypto_free_shash(smp->tfm_cmac);
3318 crypto_free_kpp(smp->tfm_ecdh);
3319 kfree_sensitive(smp);
3320 }
3321 return ERR_PTR(-ENOMEM);
3322 }
3323
3324 chan->data = smp;
3325
3326 l2cap_add_scid(chan, cid);
3327
3328 l2cap_chan_set_defaults(chan);
3329
3330 if (cid == L2CAP_CID_SMP) {
3331 u8 bdaddr_type;
3332
3333 hci_copy_identity_address(hdev, &chan->src, &bdaddr_type);
3334
3335 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
3336 chan->src_type = BDADDR_LE_PUBLIC;
3337 else
3338 chan->src_type = BDADDR_LE_RANDOM;
3339 } else {
3340 bacpy(&chan->src, &hdev->bdaddr);
3341 chan->src_type = BDADDR_BREDR;
3342 }
3343
3344 chan->state = BT_LISTEN;
3345 chan->mode = L2CAP_MODE_BASIC;
3346 chan->imtu = L2CAP_DEFAULT_MTU;
3347 chan->ops = &smp_root_chan_ops;
3348
3349 /* Set correct nesting level for a parent/listening channel */
3350 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
3351
3352 return chan;
3353}
3354
3355static void smp_del_chan(struct l2cap_chan *chan)
3356{
3357 struct smp_dev *smp;
3358
3359 BT_DBG("chan %p", chan);
3360
3361 smp = chan->data;
3362 if (smp) {
3363 chan->data = NULL;
3364 crypto_free_shash(smp->tfm_cmac);
3365 crypto_free_kpp(smp->tfm_ecdh);
3366 kfree_sensitive(smp);
3367 }
3368
3369 l2cap_chan_put(chan);
3370}
3371
3372int smp_force_bredr(struct hci_dev *hdev, bool enable)
3373{
3374 if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3375 return -EALREADY;
3376
3377 if (enable) {
3378 struct l2cap_chan *chan;
3379
3380 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3381 if (IS_ERR(chan))
3382 return PTR_ERR(chan);
3383
3384 hdev->smp_bredr_data = chan;
3385 } else {
3386 struct l2cap_chan *chan;
3387
3388 chan = hdev->smp_bredr_data;
3389 hdev->smp_bredr_data = NULL;
3390 smp_del_chan(chan);
3391 }
3392
3393 hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP);
3394
3395 return 0;
3396}
3397
3398int smp_register(struct hci_dev *hdev)
3399{
3400 struct l2cap_chan *chan;
3401
3402 bt_dev_dbg(hdev, "");
3403
3404 /* If the controller does not support Low Energy operation, then
3405 * there is also no need to register any SMP channel.
3406 */
3407 if (!lmp_le_capable(hdev))
3408 return 0;
3409
3410 if (WARN_ON(hdev->smp_data)) {
3411 chan = hdev->smp_data;
3412 hdev->smp_data = NULL;
3413 smp_del_chan(chan);
3414 }
3415
3416 chan = smp_add_cid(hdev, L2CAP_CID_SMP);
3417 if (IS_ERR(chan))
3418 return PTR_ERR(chan);
3419
3420 hdev->smp_data = chan;
3421
3422 if (!lmp_sc_capable(hdev)) {
3423 /* Flag can be already set here (due to power toggle) */
3424 if (!hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3425 return 0;
3426 }
3427
3428 if (WARN_ON(hdev->smp_bredr_data)) {
3429 chan = hdev->smp_bredr_data;
3430 hdev->smp_bredr_data = NULL;
3431 smp_del_chan(chan);
3432 }
3433
3434 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3435 if (IS_ERR(chan)) {
3436 int err = PTR_ERR(chan);
3437 chan = hdev->smp_data;
3438 hdev->smp_data = NULL;
3439 smp_del_chan(chan);
3440 return err;
3441 }
3442
3443 hdev->smp_bredr_data = chan;
3444
3445 return 0;
3446}
3447
3448void smp_unregister(struct hci_dev *hdev)
3449{
3450 struct l2cap_chan *chan;
3451
3452 if (hdev->smp_bredr_data) {
3453 chan = hdev->smp_bredr_data;
3454 hdev->smp_bredr_data = NULL;
3455 smp_del_chan(chan);
3456 }
3457
3458 if (hdev->smp_data) {
3459 chan = hdev->smp_data;
3460 hdev->smp_data = NULL;
3461 smp_del_chan(chan);
3462 }
3463}
3464
3465#if IS_ENABLED(CONFIG_BT_SELFTEST_SMP)
3466
3467static int __init test_debug_key(struct crypto_kpp *tfm_ecdh)
3468{
3469 u8 pk[64];
3470 int err;
3471
3472 err = set_ecdh_privkey(tfm_ecdh, debug_sk);
3473 if (err)
3474 return err;
3475
3476 err = generate_ecdh_public_key(tfm_ecdh, pk);
3477 if (err)
3478 return err;
3479
3480 if (crypto_memneq(pk, debug_pk, 64))
3481 return -EINVAL;
3482
3483 return 0;
3484}
3485
3486static int __init test_ah(void)
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(irk, r, res);
3497 if (err)
3498 return err;
3499
3500 if (crypto_memneq(res, exp, 3))
3501 return -EINVAL;
3502
3503 return 0;
3504}
3505
3506static int __init test_c1(void)
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(k, r, preq, pres, _iat, &ia, _rat, &ra, res);
3527 if (err)
3528 return err;
3529
3530 if (crypto_memneq(res, exp, 16))
3531 return -EINVAL;
3532
3533 return 0;
3534}
3535
3536static int __init test_s1(void)
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(k, r1, r2, res);
3552 if (err)
3553 return err;
3554
3555 if (crypto_memneq(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 (crypto_memneq(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 (crypto_memneq(mackey, exp_mackey, 16))
3622 return -EINVAL;
3623
3624 if (crypto_memneq(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 (crypto_memneq(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 (crypto_memneq(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_shash *tfm_cmac,
3733 struct crypto_kpp *tfm_ecdh)
3734{
3735 ktime_t calltime, delta, rettime;
3736 unsigned long long duration;
3737 int err;
3738
3739 calltime = ktime_get();
3740
3741 err = test_debug_key(tfm_ecdh);
3742 if (err) {
3743 BT_ERR("debug_key test failed");
3744 goto done;
3745 }
3746
3747 err = test_ah();
3748 if (err) {
3749 BT_ERR("smp_ah test failed");
3750 goto done;
3751 }
3752
3753 err = test_c1();
3754 if (err) {
3755 BT_ERR("smp_c1 test failed");
3756 goto done;
3757 }
3758
3759 err = test_s1();
3760 if (err) {
3761 BT_ERR("smp_s1 test failed");
3762 goto done;
3763 }
3764
3765 err = test_f4(tfm_cmac);
3766 if (err) {
3767 BT_ERR("smp_f4 test failed");
3768 goto done;
3769 }
3770
3771 err = test_f5(tfm_cmac);
3772 if (err) {
3773 BT_ERR("smp_f5 test failed");
3774 goto done;
3775 }
3776
3777 err = test_f6(tfm_cmac);
3778 if (err) {
3779 BT_ERR("smp_f6 test failed");
3780 goto done;
3781 }
3782
3783 err = test_g2(tfm_cmac);
3784 if (err) {
3785 BT_ERR("smp_g2 test failed");
3786 goto done;
3787 }
3788
3789 err = test_h6(tfm_cmac);
3790 if (err) {
3791 BT_ERR("smp_h6 test failed");
3792 goto done;
3793 }
3794
3795 rettime = ktime_get();
3796 delta = ktime_sub(rettime, calltime);
3797 duration = (unsigned long long) ktime_to_ns(delta) >> 10;
3798
3799 BT_INFO("SMP test passed in %llu usecs", duration);
3800
3801done:
3802 if (!err)
3803 snprintf(test_smp_buffer, sizeof(test_smp_buffer),
3804 "PASS (%llu usecs)\n", duration);
3805 else
3806 snprintf(test_smp_buffer, sizeof(test_smp_buffer), "FAIL\n");
3807
3808 debugfs_create_file("selftest_smp", 0444, bt_debugfs, NULL,
3809 &test_smp_fops);
3810
3811 return err;
3812}
3813
3814int __init bt_selftest_smp(void)
3815{
3816 struct crypto_shash *tfm_cmac;
3817 struct crypto_kpp *tfm_ecdh;
3818 int err;
3819
3820 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
3821 if (IS_ERR(tfm_cmac)) {
3822 BT_ERR("Unable to create CMAC crypto context");
3823 return PTR_ERR(tfm_cmac);
3824 }
3825
3826 tfm_ecdh = crypto_alloc_kpp("ecdh-nist-p256", 0, 0);
3827 if (IS_ERR(tfm_ecdh)) {
3828 BT_ERR("Unable to create ECDH crypto context");
3829 crypto_free_shash(tfm_cmac);
3830 return PTR_ERR(tfm_ecdh);
3831 }
3832
3833 err = run_selftests(tfm_cmac, tfm_ecdh);
3834
3835 crypto_free_shash(tfm_cmac);
3836 crypto_free_kpp(tfm_ecdh);
3837
3838 return err;
3839}
3840
3841#endif