]> git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - net/bluetooth/smp.c
projects / mirror_ubuntu-bionic-kernel.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
tipc: fix node keep alive interval calculation
[mirror_ubuntu-bionic-kernel.git] / net / bluetooth / smp.c
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/algapi.h>
27 #include <crypto/b128ops.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 * accidentially 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
68 enum {
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
84 struct 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 u8 min_key_size;
92 u8 max_key_size;
93
94 struct crypto_cipher *tfm_aes;
95 struct crypto_shash *tfm_cmac;
96 struct crypto_kpp *tfm_ecdh;
97 };
98
99 struct smp_chan {
100 struct l2cap_conn *conn;
101 struct delayed_work security_timer;
102 unsigned long allow_cmd; /* Bitmask of allowed commands */
103
104 u8 preq[7]; /* SMP Pairing Request */
105 u8 prsp[7]; /* SMP Pairing Response */
106 u8 prnd[16]; /* SMP Pairing Random (local) */
107 u8 rrnd[16]; /* SMP Pairing Random (remote) */
108 u8 pcnf[16]; /* SMP Pairing Confirm */
109 u8 tk[16]; /* SMP Temporary Key */
110 u8 rr[16]; /* Remote OOB ra/rb value */
111 u8 lr[16]; /* Local OOB ra/rb value */
112 u8 enc_key_size;
113 u8 remote_key_dist;
114 bdaddr_t id_addr;
115 u8 id_addr_type;
116 u8 irk[16];
117 struct smp_csrk *csrk;
118 struct smp_csrk *slave_csrk;
119 struct smp_ltk *ltk;
120 struct smp_ltk *slave_ltk;
121 struct smp_irk *remote_irk;
122 u8 *link_key;
123 unsigned long flags;
124 u8 method;
125 u8 passkey_round;
126
127 /* Secure Connections variables */
128 u8 local_pk[64];
129 u8 remote_pk[64];
130 u8 dhkey[32];
131 u8 mackey[16];
132
133 struct crypto_cipher *tfm_aes;
134 struct crypto_shash *tfm_cmac;
135 struct crypto_kpp *tfm_ecdh;
136 };
137
138 /* These debug key values are defined in the SMP section of the core
139 * specification. debug_pk is the public debug key and debug_sk the
140 * private debug key.
141 */
142 static const u8 debug_pk[64] = {
143 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
144 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
145 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
146 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20,
147
148 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74,
149 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76,
150 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63,
151 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc,
152 };
153
154 static const u8 debug_sk[32] = {
155 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58,
156 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a,
157 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74,
158 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f,
159 };
160
161 static inline void swap_buf(const u8 *src, u8 *dst, size_t len)
162 {
163 size_t i;
164
165 for (i = 0; i < len; i++)
166 dst[len - 1 - i] = src[i];
167 }
168
169 /* The following functions map to the LE SC SMP crypto functions
170 * AES-CMAC, f4, f5, f6, g2 and h6.
171 */
172
173 static int aes_cmac(struct crypto_shash *tfm, const u8 k[16], const u8 *m,
174 size_t len, u8 mac[16])
175 {
176 uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX];
177 SHASH_DESC_ON_STACK(desc, tfm);
178 int err;
179
180 if (len > CMAC_MSG_MAX)
181 return -EFBIG;
182
183 if (!tfm) {
184 BT_ERR("tfm %p", tfm);
185 return -EINVAL;
186 }
187
188 desc->tfm = tfm;
189 desc->flags = 0;
190
191 /* Swap key and message from LSB to MSB */
192 swap_buf(k, tmp, 16);
193 swap_buf(m, msg_msb, len);
194
195 SMP_DBG("msg (len %zu) %*phN", len, (int) len, m);
196 SMP_DBG("key %16phN", k);
197
198 err = crypto_shash_setkey(tfm, tmp, 16);
199 if (err) {
200 BT_ERR("cipher setkey failed: %d", err);
201 return err;
202 }
203
204 err = crypto_shash_digest(desc, msg_msb, len, mac_msb);
205 shash_desc_zero(desc);
206 if (err) {
207 BT_ERR("Hash computation error %d", err);
208 return err;
209 }
210
211 swap_buf(mac_msb, mac, 16);
212
213 SMP_DBG("mac %16phN", mac);
214
215 return 0;
216 }
217
218 static int smp_f4(struct crypto_shash *tfm_cmac, const u8 u[32],
219 const u8 v[32], const u8 x[16], u8 z, u8 res[16])
220 {
221 u8 m[65];
222 int err;
223
224 SMP_DBG("u %32phN", u);
225 SMP_DBG("v %32phN", v);
226 SMP_DBG("x %16phN z %02x", x, z);
227
228 m[0] = z;
229 memcpy(m + 1, v, 32);
230 memcpy(m + 33, u, 32);
231
232 err = aes_cmac(tfm_cmac, x, m, sizeof(m), res);
233 if (err)
234 return err;
235
236 SMP_DBG("res %16phN", res);
237
238 return err;
239 }
240
241 static int smp_f5(struct crypto_shash *tfm_cmac, const u8 w[32],
242 const u8 n1[16], const u8 n2[16], const u8 a1[7],
243 const u8 a2[7], u8 mackey[16], u8 ltk[16])
244 {
245 /* The btle, salt and length "magic" values are as defined in
246 * the SMP section of the Bluetooth core specification. In ASCII
247 * the btle value ends up being 'btle'. The salt is just a
248 * random number whereas length is the value 256 in little
249 * endian format.
250 */
251 const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 };
252 const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60,
253 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c };
254 const u8 length[2] = { 0x00, 0x01 };
255 u8 m[53], t[16];
256 int err;
257
258 SMP_DBG("w %32phN", w);
259 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
260 SMP_DBG("a1 %7phN a2 %7phN", a1, a2);
261
262 err = aes_cmac(tfm_cmac, salt, w, 32, t);
263 if (err)
264 return err;
265
266 SMP_DBG("t %16phN", t);
267
268 memcpy(m, length, 2);
269 memcpy(m + 2, a2, 7);
270 memcpy(m + 9, a1, 7);
271 memcpy(m + 16, n2, 16);
272 memcpy(m + 32, n1, 16);
273 memcpy(m + 48, btle, 4);
274
275 m[52] = 0; /* Counter */
276
277 err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey);
278 if (err)
279 return err;
280
281 SMP_DBG("mackey %16phN", mackey);
282
283 m[52] = 1; /* Counter */
284
285 err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk);
286 if (err)
287 return err;
288
289 SMP_DBG("ltk %16phN", ltk);
290
291 return 0;
292 }
293
294 static int smp_f6(struct crypto_shash *tfm_cmac, const u8 w[16],
295 const u8 n1[16], const u8 n2[16], const u8 r[16],
296 const u8 io_cap[3], const u8 a1[7], const u8 a2[7],
297 u8 res[16])
298 {
299 u8 m[65];
300 int err;
301
302 SMP_DBG("w %16phN", w);
303 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
304 SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2);
305
306 memcpy(m, a2, 7);
307 memcpy(m + 7, a1, 7);
308 memcpy(m + 14, io_cap, 3);
309 memcpy(m + 17, r, 16);
310 memcpy(m + 33, n2, 16);
311 memcpy(m + 49, n1, 16);
312
313 err = aes_cmac(tfm_cmac, w, m, sizeof(m), res);
314 if (err)
315 return err;
316
317 SMP_DBG("res %16phN", res);
318
319 return err;
320 }
321
322 static int smp_g2(struct crypto_shash *tfm_cmac, const u8 u[32], const u8 v[32],
323 const u8 x[16], const u8 y[16], u32 *val)
324 {
325 u8 m[80], tmp[16];
326 int err;
327
328 SMP_DBG("u %32phN", u);
329 SMP_DBG("v %32phN", v);
330 SMP_DBG("x %16phN y %16phN", x, y);
331
332 memcpy(m, y, 16);
333 memcpy(m + 16, v, 32);
334 memcpy(m + 48, u, 32);
335
336 err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp);
337 if (err)
338 return err;
339
340 *val = get_unaligned_le32(tmp);
341 *val %= 1000000;
342
343 SMP_DBG("val %06u", *val);
344
345 return 0;
346 }
347
348 static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16],
349 const u8 key_id[4], u8 res[16])
350 {
351 int err;
352
353 SMP_DBG("w %16phN key_id %4phN", w, key_id);
354
355 err = aes_cmac(tfm_cmac, w, key_id, 4, res);
356 if (err)
357 return err;
358
359 SMP_DBG("res %16phN", res);
360
361 return err;
362 }
363
364 static int smp_h7(struct crypto_shash *tfm_cmac, const u8 w[16],
365 const u8 salt[16], u8 res[16])
366 {
367 int err;
368
369 SMP_DBG("w %16phN salt %16phN", w, salt);
370
371 err = aes_cmac(tfm_cmac, salt, w, 16, res);
372 if (err)
373 return err;
374
375 SMP_DBG("res %16phN", res);
376
377 return err;
378 }
379
380 /* The following functions map to the legacy SMP crypto functions e, c1,
381 * s1 and ah.
382 */
383
384 static int smp_e(struct crypto_cipher *tfm, const u8 *k, u8 *r)
385 {
386 uint8_t tmp[16], data[16];
387 int err;
388
389 SMP_DBG("k %16phN r %16phN", k, r);
390
391 if (!tfm) {
392 BT_ERR("tfm %p", tfm);
393 return -EINVAL;
394 }
395
396 /* The most significant octet of key corresponds to k[0] */
397 swap_buf(k, tmp, 16);
398
399 err = crypto_cipher_setkey(tfm, tmp, 16);
400 if (err) {
401 BT_ERR("cipher setkey failed: %d", err);
402 return err;
403 }
404
405 /* Most significant octet of plaintextData corresponds to data[0] */
406 swap_buf(r, data, 16);
407
408 crypto_cipher_encrypt_one(tfm, data, data);
409
410 /* Most significant octet of encryptedData corresponds to data[0] */
411 swap_buf(data, r, 16);
412
413 SMP_DBG("r %16phN", r);
414
415 return err;
416 }
417
418 static int smp_c1(struct crypto_cipher *tfm_aes, const u8 k[16],
419 const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat,
420 const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16])
421 {
422 u8 p1[16], p2[16];
423 int err;
424
425 SMP_DBG("k %16phN r %16phN", k, r);
426 SMP_DBG("iat %u ia %6phN rat %u ra %6phN", _iat, ia, _rat, ra);
427 SMP_DBG("preq %7phN pres %7phN", preq, pres);
428
429 memset(p1, 0, 16);
430
431 /* p1 = pres || preq || _rat || _iat */
432 p1[0] = _iat;
433 p1[1] = _rat;
434 memcpy(p1 + 2, preq, 7);
435 memcpy(p1 + 9, pres, 7);
436
437 SMP_DBG("p1 %16phN", p1);
438
439 /* res = r XOR p1 */
440 u128_xor((u128 *) res, (u128 *) r, (u128 *) p1);
441
442 /* res = e(k, res) */
443 err = smp_e(tfm_aes, k, res);
444 if (err) {
445 BT_ERR("Encrypt data error");
446 return err;
447 }
448
449 /* p2 = padding || ia || ra */
450 memcpy(p2, ra, 6);
451 memcpy(p2 + 6, ia, 6);
452 memset(p2 + 12, 0, 4);
453
454 SMP_DBG("p2 %16phN", p2);
455
456 /* res = res XOR p2 */
457 u128_xor((u128 *) res, (u128 *) res, (u128 *) p2);
458
459 /* res = e(k, res) */
460 err = smp_e(tfm_aes, k, res);
461 if (err)
462 BT_ERR("Encrypt data error");
463
464 return err;
465 }
466
467 static int smp_s1(struct crypto_cipher *tfm_aes, const u8 k[16],
468 const u8 r1[16], const u8 r2[16], u8 _r[16])
469 {
470 int err;
471
472 /* Just least significant octets from r1 and r2 are considered */
473 memcpy(_r, r2, 8);
474 memcpy(_r + 8, r1, 8);
475
476 err = smp_e(tfm_aes, k, _r);
477 if (err)
478 BT_ERR("Encrypt data error");
479
480 return err;
481 }
482
483 static int smp_ah(struct crypto_cipher *tfm, const u8 irk[16],
484 const u8 r[3], u8 res[3])
485 {
486 u8 _res[16];
487 int err;
488
489 /* r' = padding || r */
490 memcpy(_res, r, 3);
491 memset(_res + 3, 0, 13);
492
493 err = smp_e(tfm, irk, _res);
494 if (err) {
495 BT_ERR("Encrypt error");
496 return err;
497 }
498
499 /* The output of the random address function ah is:
500 * ah(k, r) = e(k, r') mod 2^24
501 * The output of the security function e is then truncated to 24 bits
502 * by taking the least significant 24 bits of the output of e as the
503 * result of ah.
504 */
505 memcpy(res, _res, 3);
506
507 return 0;
508 }
509
510 bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16],
511 const bdaddr_t *bdaddr)
512 {
513 struct l2cap_chan *chan = hdev->smp_data;
514 struct smp_dev *smp;
515 u8 hash[3];
516 int err;
517
518 if (!chan || !chan->data)
519 return false;
520
521 smp = chan->data;
522
523 BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk);
524
525 err = smp_ah(smp->tfm_aes, irk, &bdaddr->b[3], hash);
526 if (err)
527 return false;
528
529 return !crypto_memneq(bdaddr->b, hash, 3);
530 }
531
532 int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa)
533 {
534 struct l2cap_chan *chan = hdev->smp_data;
535 struct smp_dev *smp;
536 int err;
537
538 if (!chan || !chan->data)
539 return -EOPNOTSUPP;
540
541 smp = chan->data;
542
543 get_random_bytes(&rpa->b[3], 3);
544
545 rpa->b[5] &= 0x3f; /* Clear two most significant bits */
546 rpa->b[5] |= 0x40; /* Set second most significant bit */
547
548 err = smp_ah(smp->tfm_aes, irk, &rpa->b[3], rpa->b);
549 if (err < 0)
550 return err;
551
552 BT_DBG("RPA %pMR", rpa);
553
554 return 0;
555 }
556
557 int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16])
558 {
559 struct l2cap_chan *chan = hdev->smp_data;
560 struct smp_dev *smp;
561 int err;
562
563 if (!chan || !chan->data)
564 return -EOPNOTSUPP;
565
566 smp = chan->data;
567
568 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
569 BT_DBG("Using debug keys");
570 err = set_ecdh_privkey(smp->tfm_ecdh, debug_sk);
571 if (err)
572 return err;
573 memcpy(smp->local_pk, debug_pk, 64);
574 smp->debug_key = true;
575 } else {
576 while (true) {
577 /* Generate key pair for Secure Connections */
578 err = generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk);
579 if (err)
580 return err;
581
582 /* This is unlikely, but we need to check that
583 * we didn't accidentially generate a debug key.
584 */
585 if (crypto_memneq(smp->local_pk, debug_pk, 64))
586 break;
587 }
588 smp->debug_key = false;
589 }
590
591 SMP_DBG("OOB Public Key X: %32phN", smp->local_pk);
592 SMP_DBG("OOB Public Key Y: %32phN", smp->local_pk + 32);
593
594 get_random_bytes(smp->local_rand, 16);
595
596 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->local_pk,
597 smp->local_rand, 0, hash);
598 if (err < 0)
599 return err;
600
601 memcpy(rand, smp->local_rand, 16);
602
603 smp->local_oob = true;
604
605 return 0;
606 }
607
608 static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
609 {
610 struct l2cap_chan *chan = conn->smp;
611 struct smp_chan *smp;
612 struct kvec iv[2];
613 struct msghdr msg;
614
615 if (!chan)
616 return;
617
618 BT_DBG("code 0x%2.2x", code);
619
620 iv[0].iov_base = &code;
621 iv[0].iov_len = 1;
622
623 iv[1].iov_base = data;
624 iv[1].iov_len = len;
625
626 memset(&msg, 0, sizeof(msg));
627
628 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iv, 2, 1 + len);
629
630 l2cap_chan_send(chan, &msg, 1 + len);
631
632 if (!chan->data)
633 return;
634
635 smp = chan->data;
636
637 cancel_delayed_work_sync(&smp->security_timer);
638 schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT);
639 }
640
641 static u8 authreq_to_seclevel(u8 authreq)
642 {
643 if (authreq & SMP_AUTH_MITM) {
644 if (authreq & SMP_AUTH_SC)
645 return BT_SECURITY_FIPS;
646 else
647 return BT_SECURITY_HIGH;
648 } else {
649 return BT_SECURITY_MEDIUM;
650 }
651 }
652
653 static __u8 seclevel_to_authreq(__u8 sec_level)
654 {
655 switch (sec_level) {
656 case BT_SECURITY_FIPS:
657 case BT_SECURITY_HIGH:
658 return SMP_AUTH_MITM | SMP_AUTH_BONDING;
659 case BT_SECURITY_MEDIUM:
660 return SMP_AUTH_BONDING;
661 default:
662 return SMP_AUTH_NONE;
663 }
664 }
665
666 static void build_pairing_cmd(struct l2cap_conn *conn,
667 struct smp_cmd_pairing *req,
668 struct smp_cmd_pairing *rsp, __u8 authreq)
669 {
670 struct l2cap_chan *chan = conn->smp;
671 struct smp_chan *smp = chan->data;
672 struct hci_conn *hcon = conn->hcon;
673 struct hci_dev *hdev = hcon->hdev;
674 u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT;
675
676 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
677 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
678 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
679 authreq |= SMP_AUTH_BONDING;
680 } else {
681 authreq &= ~SMP_AUTH_BONDING;
682 }
683
684 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
685 remote_dist |= SMP_DIST_ID_KEY;
686
687 if (hci_dev_test_flag(hdev, HCI_PRIVACY))
688 local_dist |= SMP_DIST_ID_KEY;
689
690 if (hci_dev_test_flag(hdev, HCI_SC_ENABLED) &&
691 (authreq & SMP_AUTH_SC)) {
692 struct oob_data *oob_data;
693 u8 bdaddr_type;
694
695 if (hci_dev_test_flag(hdev, HCI_SSP_ENABLED)) {
696 local_dist |= SMP_DIST_LINK_KEY;
697 remote_dist |= SMP_DIST_LINK_KEY;
698 }
699
700 if (hcon->dst_type == ADDR_LE_DEV_PUBLIC)
701 bdaddr_type = BDADDR_LE_PUBLIC;
702 else
703 bdaddr_type = BDADDR_LE_RANDOM;
704
705 oob_data = hci_find_remote_oob_data(hdev, &hcon->dst,
706 bdaddr_type);
707 if (oob_data && oob_data->present) {
708 set_bit(SMP_FLAG_REMOTE_OOB, &smp->flags);
709 oob_flag = SMP_OOB_PRESENT;
710 memcpy(smp->rr, oob_data->rand256, 16);
711 memcpy(smp->pcnf, oob_data->hash256, 16);
712 SMP_DBG("OOB Remote Confirmation: %16phN", smp->pcnf);
713 SMP_DBG("OOB Remote Random: %16phN", smp->rr);
714 }
715
716 } else {
717 authreq &= ~SMP_AUTH_SC;
718 }
719
720 if (rsp == NULL) {
721 req->io_capability = conn->hcon->io_capability;
722 req->oob_flag = oob_flag;
723 req->max_key_size = SMP_DEV(hdev)->max_key_size;
724 req->init_key_dist = local_dist;
725 req->resp_key_dist = remote_dist;
726 req->auth_req = (authreq & AUTH_REQ_MASK(hdev));
727
728 smp->remote_key_dist = remote_dist;
729 return;
730 }
731
732 rsp->io_capability = conn->hcon->io_capability;
733 rsp->oob_flag = oob_flag;
734 rsp->max_key_size = SMP_DEV(hdev)->max_key_size;
735 rsp->init_key_dist = req->init_key_dist & remote_dist;
736 rsp->resp_key_dist = req->resp_key_dist & local_dist;
737 rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev));
738
739 smp->remote_key_dist = rsp->init_key_dist;
740 }
741
742 static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)
743 {
744 struct l2cap_chan *chan = conn->smp;
745 struct hci_dev *hdev = conn->hcon->hdev;
746 struct smp_chan *smp = chan->data;
747
748 if (max_key_size > SMP_DEV(hdev)->max_key_size ||
749 max_key_size < SMP_MIN_ENC_KEY_SIZE)
750 return SMP_ENC_KEY_SIZE;
751
752 smp->enc_key_size = max_key_size;
753
754 return 0;
755 }
756
757 static void smp_chan_destroy(struct l2cap_conn *conn)
758 {
759 struct l2cap_chan *chan = conn->smp;
760 struct smp_chan *smp = chan->data;
761 struct hci_conn *hcon = conn->hcon;
762 bool complete;
763
764 BUG_ON(!smp);
765
766 cancel_delayed_work_sync(&smp->security_timer);
767
768 complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags);
769 mgmt_smp_complete(hcon, complete);
770
771 kzfree(smp->csrk);
772 kzfree(smp->slave_csrk);
773 kzfree(smp->link_key);
774
775 crypto_free_cipher(smp->tfm_aes);
776 crypto_free_shash(smp->tfm_cmac);
777 crypto_free_kpp(smp->tfm_ecdh);
778
779 /* Ensure that we don't leave any debug key around if debug key
780 * support hasn't been explicitly enabled.
781 */
782 if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG &&
783 !hci_dev_test_flag(hcon->hdev, HCI_KEEP_DEBUG_KEYS)) {
784 list_del_rcu(&smp->ltk->list);
785 kfree_rcu(smp->ltk, rcu);
786 smp->ltk = NULL;
787 }
788
789 /* If pairing failed clean up any keys we might have */
790 if (!complete) {
791 if (smp->ltk) {
792 list_del_rcu(&smp->ltk->list);
793 kfree_rcu(smp->ltk, rcu);
794 }
795
796 if (smp->slave_ltk) {
797 list_del_rcu(&smp->slave_ltk->list);
798 kfree_rcu(smp->slave_ltk, rcu);
799 }
800
801 if (smp->remote_irk) {
802 list_del_rcu(&smp->remote_irk->list);
803 kfree_rcu(smp->remote_irk, rcu);
804 }
805 }
806
807 chan->data = NULL;
808 kzfree(smp);
809 hci_conn_drop(hcon);
810 }
811
812 static void smp_failure(struct l2cap_conn *conn, u8 reason)
813 {
814 struct hci_conn *hcon = conn->hcon;
815 struct l2cap_chan *chan = conn->smp;
816
817 if (reason)
818 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
819 &reason);
820
821 mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE);
822
823 if (chan->data)
824 smp_chan_destroy(conn);
825 }
826
827 #define JUST_WORKS 0x00
828 #define JUST_CFM 0x01
829 #define REQ_PASSKEY 0x02
830 #define CFM_PASSKEY 0x03
831 #define REQ_OOB 0x04
832 #define DSP_PASSKEY 0x05
833 #define OVERLAP 0xFF
834
835 static const u8 gen_method[5][5] = {
836 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
837 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
838 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
839 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
840 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP },
841 };
842
843 static const u8 sc_method[5][5] = {
844 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
845 { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
846 { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY },
847 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
848 { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
849 };
850
851 static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io)
852 {
853 /* If either side has unknown io_caps, use JUST_CFM (which gets
854 * converted later to JUST_WORKS if we're initiators.
855 */
856 if (local_io > SMP_IO_KEYBOARD_DISPLAY ||
857 remote_io > SMP_IO_KEYBOARD_DISPLAY)
858 return JUST_CFM;
859
860 if (test_bit(SMP_FLAG_SC, &smp->flags))
861 return sc_method[remote_io][local_io];
862
863 return gen_method[remote_io][local_io];
864 }
865
866 static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
867 u8 local_io, u8 remote_io)
868 {
869 struct hci_conn *hcon = conn->hcon;
870 struct l2cap_chan *chan = conn->smp;
871 struct smp_chan *smp = chan->data;
872 u32 passkey = 0;
873 int ret = 0;
874
875 /* Initialize key for JUST WORKS */
876 memset(smp->tk, 0, sizeof(smp->tk));
877 clear_bit(SMP_FLAG_TK_VALID, &smp->flags);
878
879 BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io);
880
881 /* If neither side wants MITM, either "just" confirm an incoming
882 * request or use just-works for outgoing ones. The JUST_CFM
883 * will be converted to JUST_WORKS if necessary later in this
884 * function. If either side has MITM look up the method from the
885 * table.
886 */
887 if (!(auth & SMP_AUTH_MITM))
888 smp->method = JUST_CFM;
889 else
890 smp->method = get_auth_method(smp, local_io, remote_io);
891
892 /* Don't confirm locally initiated pairing attempts */
893 if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR,
894 &smp->flags))
895 smp->method = JUST_WORKS;
896
897 /* Don't bother user space with no IO capabilities */
898 if (smp->method == JUST_CFM &&
899 hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
900 smp->method = JUST_WORKS;
901
902 /* If Just Works, Continue with Zero TK */
903 if (smp->method == JUST_WORKS) {
904 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
905 return 0;
906 }
907
908 /* If this function is used for SC -> legacy fallback we
909 * can only recover the just-works case.
910 */
911 if (test_bit(SMP_FLAG_SC, &smp->flags))
912 return -EINVAL;
913
914 /* Not Just Works/Confirm results in MITM Authentication */
915 if (smp->method != JUST_CFM) {
916 set_bit(SMP_FLAG_MITM_AUTH, &smp->flags);
917 if (hcon->pending_sec_level < BT_SECURITY_HIGH)
918 hcon->pending_sec_level = BT_SECURITY_HIGH;
919 }
920
921 /* If both devices have Keyoard-Display I/O, the master
922 * Confirms and the slave Enters the passkey.
923 */
924 if (smp->method == OVERLAP) {
925 if (hcon->role == HCI_ROLE_MASTER)
926 smp->method = CFM_PASSKEY;
927 else
928 smp->method = REQ_PASSKEY;
929 }
930
931 /* Generate random passkey. */
932 if (smp->method == CFM_PASSKEY) {
933 memset(smp->tk, 0, sizeof(smp->tk));
934 get_random_bytes(&passkey, sizeof(passkey));
935 passkey %= 1000000;
936 put_unaligned_le32(passkey, smp->tk);
937 BT_DBG("PassKey: %d", passkey);
938 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
939 }
940
941 if (smp->method == REQ_PASSKEY)
942 ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst,
943 hcon->type, hcon->dst_type);
944 else if (smp->method == JUST_CFM)
945 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
946 hcon->type, hcon->dst_type,
947 passkey, 1);
948 else
949 ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst,
950 hcon->type, hcon->dst_type,
951 passkey, 0);
952
953 return ret;
954 }
955
956 static u8 smp_confirm(struct smp_chan *smp)
957 {
958 struct l2cap_conn *conn = smp->conn;
959 struct smp_cmd_pairing_confirm cp;
960 int ret;
961
962 BT_DBG("conn %p", conn);
963
964 ret = smp_c1(smp->tfm_aes, smp->tk, smp->prnd, smp->preq, smp->prsp,
965 conn->hcon->init_addr_type, &conn->hcon->init_addr,
966 conn->hcon->resp_addr_type, &conn->hcon->resp_addr,
967 cp.confirm_val);
968 if (ret)
969 return SMP_UNSPECIFIED;
970
971 clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
972
973 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
974
975 if (conn->hcon->out)
976 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
977 else
978 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
979
980 return 0;
981 }
982
983 static u8 smp_random(struct smp_chan *smp)
984 {
985 struct l2cap_conn *conn = smp->conn;
986 struct hci_conn *hcon = conn->hcon;
987 u8 confirm[16];
988 int ret;
989
990 if (IS_ERR_OR_NULL(smp->tfm_aes))
991 return SMP_UNSPECIFIED;
992
993 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
994
995 ret = smp_c1(smp->tfm_aes, smp->tk, smp->rrnd, smp->preq, smp->prsp,
996 hcon->init_addr_type, &hcon->init_addr,
997 hcon->resp_addr_type, &hcon->resp_addr, confirm);
998 if (ret)
999 return SMP_UNSPECIFIED;
1000
1001 if (crypto_memneq(smp->pcnf, confirm, sizeof(smp->pcnf))) {
1002 bt_dev_err(hcon->hdev, "pairing failed "
1003 "(confirmation values mismatch)");
1004 return SMP_CONFIRM_FAILED;
1005 }
1006
1007 if (hcon->out) {
1008 u8 stk[16];
1009 __le64 rand = 0;
1010 __le16 ediv = 0;
1011
1012 smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk);
1013
1014 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
1015 return SMP_UNSPECIFIED;
1016
1017 hci_le_start_enc(hcon, ediv, rand, stk, smp->enc_key_size);
1018 hcon->enc_key_size = smp->enc_key_size;
1019 set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
1020 } else {
1021 u8 stk[16], auth;
1022 __le64 rand = 0;
1023 __le16 ediv = 0;
1024
1025 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1026 smp->prnd);
1027
1028 smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk);
1029
1030 if (hcon->pending_sec_level == BT_SECURITY_HIGH)
1031 auth = 1;
1032 else
1033 auth = 0;
1034
1035 /* Even though there's no _SLAVE suffix this is the
1036 * slave STK we're adding for later lookup (the master
1037 * STK never needs to be stored).
1038 */
1039 hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1040 SMP_STK, auth, stk, smp->enc_key_size, ediv, rand);
1041 }
1042
1043 return 0;
1044 }
1045
1046 static void smp_notify_keys(struct l2cap_conn *conn)
1047 {
1048 struct l2cap_chan *chan = conn->smp;
1049 struct smp_chan *smp = chan->data;
1050 struct hci_conn *hcon = conn->hcon;
1051 struct hci_dev *hdev = hcon->hdev;
1052 struct smp_cmd_pairing *req = (void *) &smp->preq[1];
1053 struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1];
1054 bool persistent;
1055
1056 if (hcon->type == ACL_LINK) {
1057 if (hcon->key_type == HCI_LK_DEBUG_COMBINATION)
1058 persistent = false;
1059 else
1060 persistent = !test_bit(HCI_CONN_FLUSH_KEY,
1061 &hcon->flags);
1062 } else {
1063 /* The LTKs, IRKs and CSRKs should be persistent only if
1064 * both sides had the bonding bit set in their
1065 * authentication requests.
1066 */
1067 persistent = !!((req->auth_req & rsp->auth_req) &
1068 SMP_AUTH_BONDING);
1069 }
1070
1071 if (smp->remote_irk) {
1072 mgmt_new_irk(hdev, smp->remote_irk, persistent);
1073
1074 /* Now that user space can be considered to know the
1075 * identity address track the connection based on it
1076 * from now on (assuming this is an LE link).
1077 */
1078 if (hcon->type == LE_LINK) {
1079 bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
1080 hcon->dst_type = smp->remote_irk->addr_type;
1081 queue_work(hdev->workqueue, &conn->id_addr_update_work);
1082 }
1083 }
1084
1085 if (smp->csrk) {
1086 smp->csrk->bdaddr_type = hcon->dst_type;
1087 bacpy(&smp->csrk->bdaddr, &hcon->dst);
1088 mgmt_new_csrk(hdev, smp->csrk, persistent);
1089 }
1090
1091 if (smp->slave_csrk) {
1092 smp->slave_csrk->bdaddr_type = hcon->dst_type;
1093 bacpy(&smp->slave_csrk->bdaddr, &hcon->dst);
1094 mgmt_new_csrk(hdev, smp->slave_csrk, persistent);
1095 }
1096
1097 if (smp->ltk) {
1098 smp->ltk->bdaddr_type = hcon->dst_type;
1099 bacpy(&smp->ltk->bdaddr, &hcon->dst);
1100 mgmt_new_ltk(hdev, smp->ltk, persistent);
1101 }
1102
1103 if (smp->slave_ltk) {
1104 smp->slave_ltk->bdaddr_type = hcon->dst_type;
1105 bacpy(&smp->slave_ltk->bdaddr, &hcon->dst);
1106 mgmt_new_ltk(hdev, smp->slave_ltk, persistent);
1107 }
1108
1109 if (smp->link_key) {
1110 struct link_key *key;
1111 u8 type;
1112
1113 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1114 type = HCI_LK_DEBUG_COMBINATION;
1115 else if (hcon->sec_level == BT_SECURITY_FIPS)
1116 type = HCI_LK_AUTH_COMBINATION_P256;
1117 else
1118 type = HCI_LK_UNAUTH_COMBINATION_P256;
1119
1120 key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst,
1121 smp->link_key, type, 0, &persistent);
1122 if (key) {
1123 mgmt_new_link_key(hdev, key, persistent);
1124
1125 /* Don't keep debug keys around if the relevant
1126 * flag is not set.
1127 */
1128 if (!hci_dev_test_flag(hdev, HCI_KEEP_DEBUG_KEYS) &&
1129 key->type == HCI_LK_DEBUG_COMBINATION) {
1130 list_del_rcu(&key->list);
1131 kfree_rcu(key, rcu);
1132 }
1133 }
1134 }
1135 }
1136
1137 static void sc_add_ltk(struct smp_chan *smp)
1138 {
1139 struct hci_conn *hcon = smp->conn->hcon;
1140 u8 key_type, auth;
1141
1142 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1143 key_type = SMP_LTK_P256_DEBUG;
1144 else
1145 key_type = SMP_LTK_P256;
1146
1147 if (hcon->pending_sec_level == BT_SECURITY_FIPS)
1148 auth = 1;
1149 else
1150 auth = 0;
1151
1152 smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1153 key_type, auth, smp->tk, smp->enc_key_size,
1154 0, 0);
1155 }
1156
1157 static void sc_generate_link_key(struct smp_chan *smp)
1158 {
1159 /* From core spec. Spells out in ASCII as 'lebr'. */
1160 const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c };
1161
1162 smp->link_key = kzalloc(16, GFP_KERNEL);
1163 if (!smp->link_key)
1164 return;
1165
1166 if (test_bit(SMP_FLAG_CT2, &smp->flags)) {
1167 /* SALT = 0x00000000000000000000000000000000746D7031 */
1168 const u8 salt[16] = { 0x31, 0x70, 0x6d, 0x74 };
1169
1170 if (smp_h7(smp->tfm_cmac, smp->tk, salt, smp->link_key)) {
1171 kzfree(smp->link_key);
1172 smp->link_key = NULL;
1173 return;
1174 }
1175 } else {
1176 /* From core spec. Spells out in ASCII as 'tmp1'. */
1177 const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 };
1178
1179 if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) {
1180 kzfree(smp->link_key);
1181 smp->link_key = NULL;
1182 return;
1183 }
1184 }
1185
1186 if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) {
1187 kzfree(smp->link_key);
1188 smp->link_key = NULL;
1189 return;
1190 }
1191 }
1192
1193 static void smp_allow_key_dist(struct smp_chan *smp)
1194 {
1195 /* Allow the first expected phase 3 PDU. The rest of the PDUs
1196 * will be allowed in each PDU handler to ensure we receive
1197 * them in the correct order.
1198 */
1199 if (smp->remote_key_dist & SMP_DIST_ENC_KEY)
1200 SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO);
1201 else if (smp->remote_key_dist & SMP_DIST_ID_KEY)
1202 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
1203 else if (smp->remote_key_dist & SMP_DIST_SIGN)
1204 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
1205 }
1206
1207 static void sc_generate_ltk(struct smp_chan *smp)
1208 {
1209 /* From core spec. Spells out in ASCII as 'brle'. */
1210 const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 };
1211 struct hci_conn *hcon = smp->conn->hcon;
1212 struct hci_dev *hdev = hcon->hdev;
1213 struct link_key *key;
1214
1215 key = hci_find_link_key(hdev, &hcon->dst);
1216 if (!key) {
1217 bt_dev_err(hdev, "no Link Key found to generate LTK");
1218 return;
1219 }
1220
1221 if (key->type == HCI_LK_DEBUG_COMBINATION)
1222 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1223
1224 if (test_bit(SMP_FLAG_CT2, &smp->flags)) {
1225 /* SALT = 0x00000000000000000000000000000000746D7032 */
1226 const u8 salt[16] = { 0x32, 0x70, 0x6d, 0x74 };
1227
1228 if (smp_h7(smp->tfm_cmac, key->val, salt, smp->tk))
1229 return;
1230 } else {
1231 /* From core spec. Spells out in ASCII as 'tmp2'. */
1232 const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 };
1233
1234 if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk))
1235 return;
1236 }
1237
1238 if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk))
1239 return;
1240
1241 sc_add_ltk(smp);
1242 }
1243
1244 static void smp_distribute_keys(struct smp_chan *smp)
1245 {
1246 struct smp_cmd_pairing *req, *rsp;
1247 struct l2cap_conn *conn = smp->conn;
1248 struct hci_conn *hcon = conn->hcon;
1249 struct hci_dev *hdev = hcon->hdev;
1250 __u8 *keydist;
1251
1252 BT_DBG("conn %p", conn);
1253
1254 rsp = (void *) &smp->prsp[1];
1255
1256 /* The responder sends its keys first */
1257 if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) {
1258 smp_allow_key_dist(smp);
1259 return;
1260 }
1261
1262 req = (void *) &smp->preq[1];
1263
1264 if (hcon->out) {
1265 keydist = &rsp->init_key_dist;
1266 *keydist &= req->init_key_dist;
1267 } else {
1268 keydist = &rsp->resp_key_dist;
1269 *keydist &= req->resp_key_dist;
1270 }
1271
1272 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1273 if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY))
1274 sc_generate_link_key(smp);
1275 if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY))
1276 sc_generate_ltk(smp);
1277
1278 /* Clear the keys which are generated but not distributed */
1279 *keydist &= ~SMP_SC_NO_DIST;
1280 }
1281
1282 BT_DBG("keydist 0x%x", *keydist);
1283
1284 if (*keydist & SMP_DIST_ENC_KEY) {
1285 struct smp_cmd_encrypt_info enc;
1286 struct smp_cmd_master_ident ident;
1287 struct smp_ltk *ltk;
1288 u8 authenticated;
1289 __le16 ediv;
1290 __le64 rand;
1291
1292 /* Make sure we generate only the significant amount of
1293 * bytes based on the encryption key size, and set the rest
1294 * of the value to zeroes.
1295 */
1296 get_random_bytes(enc.ltk, smp->enc_key_size);
1297 memset(enc.ltk + smp->enc_key_size, 0,
1298 sizeof(enc.ltk) - smp->enc_key_size);
1299
1300 get_random_bytes(&ediv, sizeof(ediv));
1301 get_random_bytes(&rand, sizeof(rand));
1302
1303 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);
1304
1305 authenticated = hcon->sec_level == BT_SECURITY_HIGH;
1306 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type,
1307 SMP_LTK_SLAVE, authenticated, enc.ltk,
1308 smp->enc_key_size, ediv, rand);
1309 smp->slave_ltk = ltk;
1310
1311 ident.ediv = ediv;
1312 ident.rand = rand;
1313
1314 smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident);
1315
1316 *keydist &= ~SMP_DIST_ENC_KEY;
1317 }
1318
1319 if (*keydist & SMP_DIST_ID_KEY) {
1320 struct smp_cmd_ident_addr_info addrinfo;
1321 struct smp_cmd_ident_info idinfo;
1322
1323 memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk));
1324
1325 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);
1326
1327 /* The hci_conn contains the local identity address
1328 * after the connection has been established.
1329 *
1330 * This is true even when the connection has been
1331 * established using a resolvable random address.
1332 */
1333 bacpy(&addrinfo.bdaddr, &hcon->src);
1334 addrinfo.addr_type = hcon->src_type;
1335
1336 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo),
1337 &addrinfo);
1338
1339 *keydist &= ~SMP_DIST_ID_KEY;
1340 }
1341
1342 if (*keydist & SMP_DIST_SIGN) {
1343 struct smp_cmd_sign_info sign;
1344 struct smp_csrk *csrk;
1345
1346 /* Generate a new random key */
1347 get_random_bytes(sign.csrk, sizeof(sign.csrk));
1348
1349 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
1350 if (csrk) {
1351 if (hcon->sec_level > BT_SECURITY_MEDIUM)
1352 csrk->type = MGMT_CSRK_LOCAL_AUTHENTICATED;
1353 else
1354 csrk->type = MGMT_CSRK_LOCAL_UNAUTHENTICATED;
1355 memcpy(csrk->val, sign.csrk, sizeof(csrk->val));
1356 }
1357 smp->slave_csrk = csrk;
1358
1359 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);
1360
1361 *keydist &= ~SMP_DIST_SIGN;
1362 }
1363
1364 /* If there are still keys to be received wait for them */
1365 if (smp->remote_key_dist & KEY_DIST_MASK) {
1366 smp_allow_key_dist(smp);
1367 return;
1368 }
1369
1370 set_bit(SMP_FLAG_COMPLETE, &smp->flags);
1371 smp_notify_keys(conn);
1372
1373 smp_chan_destroy(conn);
1374 }
1375
1376 static void smp_timeout(struct work_struct *work)
1377 {
1378 struct smp_chan *smp = container_of(work, struct smp_chan,
1379 security_timer.work);
1380 struct l2cap_conn *conn = smp->conn;
1381
1382 BT_DBG("conn %p", conn);
1383
1384 hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM);
1385 }
1386
1387 static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
1388 {
1389 struct l2cap_chan *chan = conn->smp;
1390 struct smp_chan *smp;
1391
1392 smp = kzalloc(sizeof(*smp), GFP_ATOMIC);
1393 if (!smp)
1394 return NULL;
1395
1396 smp->tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
1397 if (IS_ERR(smp->tfm_aes)) {
1398 BT_ERR("Unable to create AES crypto context");
1399 goto zfree_smp;
1400 }
1401
1402 smp->tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
1403 if (IS_ERR(smp->tfm_cmac)) {
1404 BT_ERR("Unable to create CMAC crypto context");
1405 goto free_cipher;
1406 }
1407
1408 smp->tfm_ecdh = crypto_alloc_kpp("ecdh", CRYPTO_ALG_INTERNAL, 0);
1409 if (IS_ERR(smp->tfm_ecdh)) {
1410 BT_ERR("Unable to create ECDH crypto context");
1411 goto free_shash;
1412 }
1413
1414 smp->conn = conn;
1415 chan->data = smp;
1416
1417 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL);
1418
1419 INIT_DELAYED_WORK(&smp->security_timer, smp_timeout);
1420
1421 hci_conn_hold(conn->hcon);
1422
1423 return smp;
1424
1425 free_shash:
1426 crypto_free_shash(smp->tfm_cmac);
1427 free_cipher:
1428 crypto_free_cipher(smp->tfm_aes);
1429 zfree_smp:
1430 kzfree(smp);
1431 return NULL;
1432 }
1433
1434 static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16])
1435 {
1436 struct hci_conn *hcon = smp->conn->hcon;
1437 u8 *na, *nb, a[7], b[7];
1438
1439 if (hcon->out) {
1440 na = smp->prnd;
1441 nb = smp->rrnd;
1442 } else {
1443 na = smp->rrnd;
1444 nb = smp->prnd;
1445 }
1446
1447 memcpy(a, &hcon->init_addr, 6);
1448 memcpy(b, &hcon->resp_addr, 6);
1449 a[6] = hcon->init_addr_type;
1450 b[6] = hcon->resp_addr_type;
1451
1452 return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk);
1453 }
1454
1455 static void sc_dhkey_check(struct smp_chan *smp)
1456 {
1457 struct hci_conn *hcon = smp->conn->hcon;
1458 struct smp_cmd_dhkey_check check;
1459 u8 a[7], b[7], *local_addr, *remote_addr;
1460 u8 io_cap[3], r[16];
1461
1462 memcpy(a, &hcon->init_addr, 6);
1463 memcpy(b, &hcon->resp_addr, 6);
1464 a[6] = hcon->init_addr_type;
1465 b[6] = hcon->resp_addr_type;
1466
1467 if (hcon->out) {
1468 local_addr = a;
1469 remote_addr = b;
1470 memcpy(io_cap, &smp->preq[1], 3);
1471 } else {
1472 local_addr = b;
1473 remote_addr = a;
1474 memcpy(io_cap, &smp->prsp[1], 3);
1475 }
1476
1477 memset(r, 0, sizeof(r));
1478
1479 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
1480 put_unaligned_le32(hcon->passkey_notify, r);
1481
1482 if (smp->method == REQ_OOB)
1483 memcpy(r, smp->rr, 16);
1484
1485 smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap,
1486 local_addr, remote_addr, check.e);
1487
1488 smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check);
1489 }
1490
1491 static u8 sc_passkey_send_confirm(struct smp_chan *smp)
1492 {
1493 struct l2cap_conn *conn = smp->conn;
1494 struct hci_conn *hcon = conn->hcon;
1495 struct smp_cmd_pairing_confirm cfm;
1496 u8 r;
1497
1498 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1499 r |= 0x80;
1500
1501 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1502
1503 if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r,
1504 cfm.confirm_val))
1505 return SMP_UNSPECIFIED;
1506
1507 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
1508
1509 return 0;
1510 }
1511
1512 static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op)
1513 {
1514 struct l2cap_conn *conn = smp->conn;
1515 struct hci_conn *hcon = conn->hcon;
1516 struct hci_dev *hdev = hcon->hdev;
1517 u8 cfm[16], r;
1518
1519 /* Ignore the PDU if we've already done 20 rounds (0 - 19) */
1520 if (smp->passkey_round >= 20)
1521 return 0;
1522
1523 switch (smp_op) {
1524 case SMP_CMD_PAIRING_RANDOM:
1525 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1526 r |= 0x80;
1527
1528 if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
1529 smp->rrnd, r, cfm))
1530 return SMP_UNSPECIFIED;
1531
1532 if (crypto_memneq(smp->pcnf, cfm, 16))
1533 return SMP_CONFIRM_FAILED;
1534
1535 smp->passkey_round++;
1536
1537 if (smp->passkey_round == 20) {
1538 /* Generate MacKey and LTK */
1539 if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk))
1540 return SMP_UNSPECIFIED;
1541 }
1542
1543 /* The round is only complete when the initiator
1544 * receives pairing random.
1545 */
1546 if (!hcon->out) {
1547 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1548 sizeof(smp->prnd), smp->prnd);
1549 if (smp->passkey_round == 20)
1550 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1551 else
1552 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1553 return 0;
1554 }
1555
1556 /* Start the next round */
1557 if (smp->passkey_round != 20)
1558 return sc_passkey_round(smp, 0);
1559
1560 /* Passkey rounds are complete - start DHKey Check */
1561 sc_dhkey_check(smp);
1562 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1563
1564 break;
1565
1566 case SMP_CMD_PAIRING_CONFIRM:
1567 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
1568 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
1569 return 0;
1570 }
1571
1572 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1573
1574 if (hcon->out) {
1575 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1576 sizeof(smp->prnd), smp->prnd);
1577 return 0;
1578 }
1579
1580 return sc_passkey_send_confirm(smp);
1581
1582 case SMP_CMD_PUBLIC_KEY:
1583 default:
1584 /* Initiating device starts the round */
1585 if (!hcon->out)
1586 return 0;
1587
1588 BT_DBG("%s Starting passkey round %u", hdev->name,
1589 smp->passkey_round + 1);
1590
1591 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1592
1593 return sc_passkey_send_confirm(smp);
1594 }
1595
1596 return 0;
1597 }
1598
1599 static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey)
1600 {
1601 struct l2cap_conn *conn = smp->conn;
1602 struct hci_conn *hcon = conn->hcon;
1603 u8 smp_op;
1604
1605 clear_bit(SMP_FLAG_WAIT_USER, &smp->flags);
1606
1607 switch (mgmt_op) {
1608 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1609 smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED);
1610 return 0;
1611 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1612 smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED);
1613 return 0;
1614 case MGMT_OP_USER_PASSKEY_REPLY:
1615 hcon->passkey_notify = le32_to_cpu(passkey);
1616 smp->passkey_round = 0;
1617
1618 if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags))
1619 smp_op = SMP_CMD_PAIRING_CONFIRM;
1620 else
1621 smp_op = 0;
1622
1623 if (sc_passkey_round(smp, smp_op))
1624 return -EIO;
1625
1626 return 0;
1627 }
1628
1629 /* Initiator sends DHKey check first */
1630 if (hcon->out) {
1631 sc_dhkey_check(smp);
1632 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1633 } else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) {
1634 sc_dhkey_check(smp);
1635 sc_add_ltk(smp);
1636 }
1637
1638 return 0;
1639 }
1640
1641 int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
1642 {
1643 struct l2cap_conn *conn = hcon->l2cap_data;
1644 struct l2cap_chan *chan;
1645 struct smp_chan *smp;
1646 u32 value;
1647 int err;
1648
1649 BT_DBG("");
1650
1651 if (!conn)
1652 return -ENOTCONN;
1653
1654 chan = conn->smp;
1655 if (!chan)
1656 return -ENOTCONN;
1657
1658 l2cap_chan_lock(chan);
1659 if (!chan->data) {
1660 err = -ENOTCONN;
1661 goto unlock;
1662 }
1663
1664 smp = chan->data;
1665
1666 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1667 err = sc_user_reply(smp, mgmt_op, passkey);
1668 goto unlock;
1669 }
1670
1671 switch (mgmt_op) {
1672 case MGMT_OP_USER_PASSKEY_REPLY:
1673 value = le32_to_cpu(passkey);
1674 memset(smp->tk, 0, sizeof(smp->tk));
1675 BT_DBG("PassKey: %d", value);
1676 put_unaligned_le32(value, smp->tk);
1677 /* Fall Through */
1678 case MGMT_OP_USER_CONFIRM_REPLY:
1679 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
1680 break;
1681 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1682 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1683 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1684 err = 0;
1685 goto unlock;
1686 default:
1687 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1688 err = -EOPNOTSUPP;
1689 goto unlock;
1690 }
1691
1692 err = 0;
1693
1694 /* If it is our turn to send Pairing Confirm, do so now */
1695 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) {
1696 u8 rsp = smp_confirm(smp);
1697 if (rsp)
1698 smp_failure(conn, rsp);
1699 }
1700
1701 unlock:
1702 l2cap_chan_unlock(chan);
1703 return err;
1704 }
1705
1706 static void build_bredr_pairing_cmd(struct smp_chan *smp,
1707 struct smp_cmd_pairing *req,
1708 struct smp_cmd_pairing *rsp)
1709 {
1710 struct l2cap_conn *conn = smp->conn;
1711 struct hci_dev *hdev = conn->hcon->hdev;
1712 u8 local_dist = 0, remote_dist = 0;
1713
1714 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
1715 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1716 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1717 }
1718
1719 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
1720 remote_dist |= SMP_DIST_ID_KEY;
1721
1722 if (hci_dev_test_flag(hdev, HCI_PRIVACY))
1723 local_dist |= SMP_DIST_ID_KEY;
1724
1725 if (!rsp) {
1726 memset(req, 0, sizeof(*req));
1727
1728 req->auth_req = SMP_AUTH_CT2;
1729 req->init_key_dist = local_dist;
1730 req->resp_key_dist = remote_dist;
1731 req->max_key_size = conn->hcon->enc_key_size;
1732
1733 smp->remote_key_dist = remote_dist;
1734
1735 return;
1736 }
1737
1738 memset(rsp, 0, sizeof(*rsp));
1739
1740 rsp->auth_req = SMP_AUTH_CT2;
1741 rsp->max_key_size = conn->hcon->enc_key_size;
1742 rsp->init_key_dist = req->init_key_dist & remote_dist;
1743 rsp->resp_key_dist = req->resp_key_dist & local_dist;
1744
1745 smp->remote_key_dist = rsp->init_key_dist;
1746 }
1747
1748 static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
1749 {
1750 struct smp_cmd_pairing rsp, *req = (void *) skb->data;
1751 struct l2cap_chan *chan = conn->smp;
1752 struct hci_dev *hdev = conn->hcon->hdev;
1753 struct smp_chan *smp;
1754 u8 key_size, auth, sec_level;
1755 int ret;
1756
1757 BT_DBG("conn %p", conn);
1758
1759 if (skb->len < sizeof(*req))
1760 return SMP_INVALID_PARAMS;
1761
1762 if (conn->hcon->role != HCI_ROLE_SLAVE)
1763 return SMP_CMD_NOTSUPP;
1764
1765 if (!chan->data)
1766 smp = smp_chan_create(conn);
1767 else
1768 smp = chan->data;
1769
1770 if (!smp)
1771 return SMP_UNSPECIFIED;
1772
1773 /* We didn't start the pairing, so match remote */
1774 auth = req->auth_req & AUTH_REQ_MASK(hdev);
1775
1776 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
1777 (auth & SMP_AUTH_BONDING))
1778 return SMP_PAIRING_NOTSUPP;
1779
1780 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1781 return SMP_AUTH_REQUIREMENTS;
1782
1783 smp->preq[0] = SMP_CMD_PAIRING_REQ;
1784 memcpy(&smp->preq[1], req, sizeof(*req));
1785 skb_pull(skb, sizeof(*req));
1786
1787 /* If the remote side's OOB flag is set it means it has
1788 * successfully received our local OOB data - therefore set the
1789 * flag to indicate that local OOB is in use.
1790 */
1791 if (req->oob_flag == SMP_OOB_PRESENT && SMP_DEV(hdev)->local_oob)
1792 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1793
1794 /* SMP over BR/EDR requires special treatment */
1795 if (conn->hcon->type == ACL_LINK) {
1796 /* We must have a BR/EDR SC link */
1797 if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) &&
1798 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
1799 return SMP_CROSS_TRANSP_NOT_ALLOWED;
1800
1801 set_bit(SMP_FLAG_SC, &smp->flags);
1802
1803 build_bredr_pairing_cmd(smp, req, &rsp);
1804
1805 if (req->auth_req & SMP_AUTH_CT2)
1806 set_bit(SMP_FLAG_CT2, &smp->flags);
1807
1808 key_size = min(req->max_key_size, rsp.max_key_size);
1809 if (check_enc_key_size(conn, key_size))
1810 return SMP_ENC_KEY_SIZE;
1811
1812 /* Clear bits which are generated but not distributed */
1813 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1814
1815 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1816 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1817 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1818
1819 smp_distribute_keys(smp);
1820 return 0;
1821 }
1822
1823 build_pairing_cmd(conn, req, &rsp, auth);
1824
1825 if (rsp.auth_req & SMP_AUTH_SC) {
1826 set_bit(SMP_FLAG_SC, &smp->flags);
1827
1828 if (rsp.auth_req & SMP_AUTH_CT2)
1829 set_bit(SMP_FLAG_CT2, &smp->flags);
1830 }
1831
1832 if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
1833 sec_level = BT_SECURITY_MEDIUM;
1834 else
1835 sec_level = authreq_to_seclevel(auth);
1836
1837 if (sec_level > conn->hcon->pending_sec_level)
1838 conn->hcon->pending_sec_level = sec_level;
1839
1840 /* If we need MITM check that it can be achieved */
1841 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1842 u8 method;
1843
1844 method = get_auth_method(smp, conn->hcon->io_capability,
1845 req->io_capability);
1846 if (method == JUST_WORKS || method == JUST_CFM)
1847 return SMP_AUTH_REQUIREMENTS;
1848 }
1849
1850 key_size = min(req->max_key_size, rsp.max_key_size);
1851 if (check_enc_key_size(conn, key_size))
1852 return SMP_ENC_KEY_SIZE;
1853
1854 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1855
1856 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1857 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1858
1859 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1860
1861 clear_bit(SMP_FLAG_INITIATOR, &smp->flags);
1862
1863 /* Strictly speaking we shouldn't allow Pairing Confirm for the
1864 * SC case, however some implementations incorrectly copy RFU auth
1865 * req bits from our security request, which may create a false
1866 * positive SC enablement.
1867 */
1868 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1869
1870 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1871 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
1872 /* Clear bits which are generated but not distributed */
1873 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1874 /* Wait for Public Key from Initiating Device */
1875 return 0;
1876 }
1877
1878 /* Request setup of TK */
1879 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability);
1880 if (ret)
1881 return SMP_UNSPECIFIED;
1882
1883 return 0;
1884 }
1885
1886 static u8 sc_send_public_key(struct smp_chan *smp)
1887 {
1888 struct hci_dev *hdev = smp->conn->hcon->hdev;
1889
1890 BT_DBG("");
1891
1892 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) {
1893 struct l2cap_chan *chan = hdev->smp_data;
1894 struct smp_dev *smp_dev;
1895
1896 if (!chan || !chan->data)
1897 return SMP_UNSPECIFIED;
1898
1899 smp_dev = chan->data;
1900
1901 memcpy(smp->local_pk, smp_dev->local_pk, 64);
1902 memcpy(smp->lr, smp_dev->local_rand, 16);
1903
1904 if (smp_dev->debug_key)
1905 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1906
1907 goto done;
1908 }
1909
1910 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
1911 BT_DBG("Using debug keys");
1912 if (set_ecdh_privkey(smp->tfm_ecdh, debug_sk))
1913 return SMP_UNSPECIFIED;
1914 memcpy(smp->local_pk, debug_pk, 64);
1915 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1916 } else {
1917 while (true) {
1918 /* Generate key pair for Secure Connections */
1919 if (generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk))
1920 return SMP_UNSPECIFIED;
1921
1922 /* This is unlikely, but we need to check that
1923 * we didn't accidentially generate a debug key.
1924 */
1925 if (crypto_memneq(smp->local_pk, debug_pk, 64))
1926 break;
1927 }
1928 }
1929
1930 done:
1931 SMP_DBG("Local Public Key X: %32phN", smp->local_pk);
1932 SMP_DBG("Local Public Key Y: %32phN", smp->local_pk + 32);
1933
1934 smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk);
1935
1936 return 0;
1937 }
1938
1939 static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
1940 {
1941 struct smp_cmd_pairing *req, *rsp = (void *) skb->data;
1942 struct l2cap_chan *chan = conn->smp;
1943 struct smp_chan *smp = chan->data;
1944 struct hci_dev *hdev = conn->hcon->hdev;
1945 u8 key_size, auth;
1946 int ret;
1947
1948 BT_DBG("conn %p", conn);
1949
1950 if (skb->len < sizeof(*rsp))
1951 return SMP_INVALID_PARAMS;
1952
1953 if (conn->hcon->role != HCI_ROLE_MASTER)
1954 return SMP_CMD_NOTSUPP;
1955
1956 skb_pull(skb, sizeof(*rsp));
1957
1958 req = (void *) &smp->preq[1];
1959
1960 key_size = min(req->max_key_size, rsp->max_key_size);
1961 if (check_enc_key_size(conn, key_size))
1962 return SMP_ENC_KEY_SIZE;
1963
1964 auth = rsp->auth_req & AUTH_REQ_MASK(hdev);
1965
1966 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1967 return SMP_AUTH_REQUIREMENTS;
1968
1969 /* If the remote side's OOB flag is set it means it has
1970 * successfully received our local OOB data - therefore set the
1971 * flag to indicate that local OOB is in use.
1972 */
1973 if (rsp->oob_flag == SMP_OOB_PRESENT && SMP_DEV(hdev)->local_oob)
1974 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1975
1976 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1977 memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
1978
1979 /* Update remote key distribution in case the remote cleared
1980 * some bits that we had enabled in our request.
1981 */
1982 smp->remote_key_dist &= rsp->resp_key_dist;
1983
1984 if ((req->auth_req & SMP_AUTH_CT2) && (auth & SMP_AUTH_CT2))
1985 set_bit(SMP_FLAG_CT2, &smp->flags);
1986
1987 /* For BR/EDR this means we're done and can start phase 3 */
1988 if (conn->hcon->type == ACL_LINK) {
1989 /* Clear bits which are generated but not distributed */
1990 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1991 smp_distribute_keys(smp);
1992 return 0;
1993 }
1994
1995 if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC))
1996 set_bit(SMP_FLAG_SC, &smp->flags);
1997 else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH)
1998 conn->hcon->pending_sec_level = BT_SECURITY_HIGH;
1999
2000 /* If we need MITM check that it can be achieved */
2001 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
2002 u8 method;
2003
2004 method = get_auth_method(smp, req->io_capability,
2005 rsp->io_capability);
2006 if (method == JUST_WORKS || method == JUST_CFM)
2007 return SMP_AUTH_REQUIREMENTS;
2008 }
2009
2010 get_random_bytes(smp->prnd, sizeof(smp->prnd));
2011
2012 /* Update remote key distribution in case the remote cleared
2013 * some bits that we had enabled in our request.
2014 */
2015 smp->remote_key_dist &= rsp->resp_key_dist;
2016
2017 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
2018 /* Clear bits which are generated but not distributed */
2019 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
2020 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
2021 return sc_send_public_key(smp);
2022 }
2023
2024 auth |= req->auth_req;
2025
2026 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability);
2027 if (ret)
2028 return SMP_UNSPECIFIED;
2029
2030 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
2031
2032 /* Can't compose response until we have been confirmed */
2033 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
2034 return smp_confirm(smp);
2035
2036 return 0;
2037 }
2038
2039 static u8 sc_check_confirm(struct smp_chan *smp)
2040 {
2041 struct l2cap_conn *conn = smp->conn;
2042
2043 BT_DBG("");
2044
2045 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2046 return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM);
2047
2048 if (conn->hcon->out) {
2049 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2050 smp->prnd);
2051 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2052 }
2053
2054 return 0;
2055 }
2056
2057 /* Work-around for some implementations that incorrectly copy RFU bits
2058 * from our security request and thereby create the impression that
2059 * we're doing SC when in fact the remote doesn't support it.
2060 */
2061 static int fixup_sc_false_positive(struct smp_chan *smp)
2062 {
2063 struct l2cap_conn *conn = smp->conn;
2064 struct hci_conn *hcon = conn->hcon;
2065 struct hci_dev *hdev = hcon->hdev;
2066 struct smp_cmd_pairing *req, *rsp;
2067 u8 auth;
2068
2069 /* The issue is only observed when we're in slave role */
2070 if (hcon->out)
2071 return SMP_UNSPECIFIED;
2072
2073 if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) {
2074 bt_dev_err(hdev, "refusing legacy fallback in SC-only mode");
2075 return SMP_UNSPECIFIED;
2076 }
2077
2078 bt_dev_err(hdev, "trying to fall back to legacy SMP");
2079
2080 req = (void *) &smp->preq[1];
2081 rsp = (void *) &smp->prsp[1];
2082
2083 /* Rebuild key dist flags which may have been cleared for SC */
2084 smp->remote_key_dist = (req->init_key_dist & rsp->resp_key_dist);
2085
2086 auth = req->auth_req & AUTH_REQ_MASK(hdev);
2087
2088 if (tk_request(conn, 0, auth, rsp->io_capability, req->io_capability)) {
2089 bt_dev_err(hdev, "failed to fall back to legacy SMP");
2090 return SMP_UNSPECIFIED;
2091 }
2092
2093 clear_bit(SMP_FLAG_SC, &smp->flags);
2094
2095 return 0;
2096 }
2097
2098 static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
2099 {
2100 struct l2cap_chan *chan = conn->smp;
2101 struct smp_chan *smp = chan->data;
2102
2103 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
2104
2105 if (skb->len < sizeof(smp->pcnf))
2106 return SMP_INVALID_PARAMS;
2107
2108 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
2109 skb_pull(skb, sizeof(smp->pcnf));
2110
2111 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
2112 int ret;
2113
2114 /* Public Key exchange must happen before any other steps */
2115 if (test_bit(SMP_FLAG_REMOTE_PK, &smp->flags))
2116 return sc_check_confirm(smp);
2117
2118 BT_ERR("Unexpected SMP Pairing Confirm");
2119
2120 ret = fixup_sc_false_positive(smp);
2121 if (ret)
2122 return ret;
2123 }
2124
2125 if (conn->hcon->out) {
2126 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2127 smp->prnd);
2128 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2129 return 0;
2130 }
2131
2132 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
2133 return smp_confirm(smp);
2134
2135 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
2136
2137 return 0;
2138 }
2139
2140 static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
2141 {
2142 struct l2cap_chan *chan = conn->smp;
2143 struct smp_chan *smp = chan->data;
2144 struct hci_conn *hcon = conn->hcon;
2145 u8 *pkax, *pkbx, *na, *nb;
2146 u32 passkey;
2147 int err;
2148
2149 BT_DBG("conn %p", conn);
2150
2151 if (skb->len < sizeof(smp->rrnd))
2152 return SMP_INVALID_PARAMS;
2153
2154 memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd));
2155 skb_pull(skb, sizeof(smp->rrnd));
2156
2157 if (!test_bit(SMP_FLAG_SC, &smp->flags))
2158 return smp_random(smp);
2159
2160 if (hcon->out) {
2161 pkax = smp->local_pk;
2162 pkbx = smp->remote_pk;
2163 na = smp->prnd;
2164 nb = smp->rrnd;
2165 } else {
2166 pkax = smp->remote_pk;
2167 pkbx = smp->local_pk;
2168 na = smp->rrnd;
2169 nb = smp->prnd;
2170 }
2171
2172 if (smp->method == REQ_OOB) {
2173 if (!hcon->out)
2174 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2175 sizeof(smp->prnd), smp->prnd);
2176 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2177 goto mackey_and_ltk;
2178 }
2179
2180 /* Passkey entry has special treatment */
2181 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2182 return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM);
2183
2184 if (hcon->out) {
2185 u8 cfm[16];
2186
2187 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
2188 smp->rrnd, 0, cfm);
2189 if (err)
2190 return SMP_UNSPECIFIED;
2191
2192 if (crypto_memneq(smp->pcnf, cfm, 16))
2193 return SMP_CONFIRM_FAILED;
2194 } else {
2195 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2196 smp->prnd);
2197 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2198 }
2199
2200 mackey_and_ltk:
2201 /* Generate MacKey and LTK */
2202 err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk);
2203 if (err)
2204 return SMP_UNSPECIFIED;
2205
2206 if (smp->method == JUST_WORKS || smp->method == REQ_OOB) {
2207 if (hcon->out) {
2208 sc_dhkey_check(smp);
2209 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2210 }
2211 return 0;
2212 }
2213
2214 err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);
2215 if (err)
2216 return SMP_UNSPECIFIED;
2217
2218 err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type,
2219 hcon->dst_type, passkey, 0);
2220 if (err)
2221 return SMP_UNSPECIFIED;
2222
2223 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2224
2225 return 0;
2226 }
2227
2228 static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
2229 {
2230 struct smp_ltk *key;
2231 struct hci_conn *hcon = conn->hcon;
2232
2233 key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role);
2234 if (!key)
2235 return false;
2236
2237 if (smp_ltk_sec_level(key) < sec_level)
2238 return false;
2239
2240 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
2241 return true;
2242
2243 hci_le_start_enc(hcon, key->ediv, key->rand, key->val, key->enc_size);
2244 hcon->enc_key_size = key->enc_size;
2245
2246 /* We never store STKs for master role, so clear this flag */
2247 clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
2248
2249 return true;
2250 }
2251
2252 bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level,
2253 enum smp_key_pref key_pref)
2254 {
2255 if (sec_level == BT_SECURITY_LOW)
2256 return true;
2257
2258 /* If we're encrypted with an STK but the caller prefers using
2259 * LTK claim insufficient security. This way we allow the
2260 * connection to be re-encrypted with an LTK, even if the LTK
2261 * provides the same level of security. Only exception is if we
2262 * don't have an LTK (e.g. because of key distribution bits).
2263 */
2264 if (key_pref == SMP_USE_LTK &&
2265 test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) &&
2266 hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role))
2267 return false;
2268
2269 if (hcon->sec_level >= sec_level)
2270 return true;
2271
2272 return false;
2273 }
2274
2275 static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
2276 {
2277 struct smp_cmd_security_req *rp = (void *) skb->data;
2278 struct smp_cmd_pairing cp;
2279 struct hci_conn *hcon = conn->hcon;
2280 struct hci_dev *hdev = hcon->hdev;
2281 struct smp_chan *smp;
2282 u8 sec_level, auth;
2283
2284 BT_DBG("conn %p", conn);
2285
2286 if (skb->len < sizeof(*rp))
2287 return SMP_INVALID_PARAMS;
2288
2289 if (hcon->role != HCI_ROLE_MASTER)
2290 return SMP_CMD_NOTSUPP;
2291
2292 auth = rp->auth_req & AUTH_REQ_MASK(hdev);
2293
2294 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
2295 return SMP_AUTH_REQUIREMENTS;
2296
2297 if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
2298 sec_level = BT_SECURITY_MEDIUM;
2299 else
2300 sec_level = authreq_to_seclevel(auth);
2301
2302 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) {
2303 /* If link is already encrypted with sufficient security we
2304 * still need refresh encryption as per Core Spec 5.0 Vol 3,
2305 * Part H 2.4.6
2306 */
2307 smp_ltk_encrypt(conn, hcon->sec_level);
2308 return 0;
2309 }
2310
2311 if (sec_level > hcon->pending_sec_level)
2312 hcon->pending_sec_level = sec_level;
2313
2314 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2315 return 0;
2316
2317 smp = smp_chan_create(conn);
2318 if (!smp)
2319 return SMP_UNSPECIFIED;
2320
2321 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
2322 (auth & SMP_AUTH_BONDING))
2323 return SMP_PAIRING_NOTSUPP;
2324
2325 skb_pull(skb, sizeof(*rp));
2326
2327 memset(&cp, 0, sizeof(cp));
2328 build_pairing_cmd(conn, &cp, NULL, auth);
2329
2330 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2331 memcpy(&smp->preq[1], &cp, sizeof(cp));
2332
2333 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2334 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2335
2336 return 0;
2337 }
2338
2339 int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
2340 {
2341 struct l2cap_conn *conn = hcon->l2cap_data;
2342 struct l2cap_chan *chan;
2343 struct smp_chan *smp;
2344 __u8 authreq;
2345 int ret;
2346
2347 BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);
2348
2349 /* This may be NULL if there's an unexpected disconnection */
2350 if (!conn)
2351 return 1;
2352
2353 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED))
2354 return 1;
2355
2356 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
2357 return 1;
2358
2359 if (sec_level > hcon->pending_sec_level)
2360 hcon->pending_sec_level = sec_level;
2361
2362 if (hcon->role == HCI_ROLE_MASTER)
2363 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2364 return 0;
2365
2366 chan = conn->smp;
2367 if (!chan) {
2368 bt_dev_err(hcon->hdev, "security requested but not available");
2369 return 1;
2370 }
2371
2372 l2cap_chan_lock(chan);
2373
2374 /* If SMP is already in progress ignore this request */
2375 if (chan->data) {
2376 ret = 0;
2377 goto unlock;
2378 }
2379
2380 smp = smp_chan_create(conn);
2381 if (!smp) {
2382 ret = 1;
2383 goto unlock;
2384 }
2385
2386 authreq = seclevel_to_authreq(sec_level);
2387
2388 if (hci_dev_test_flag(hcon->hdev, HCI_SC_ENABLED)) {
2389 authreq |= SMP_AUTH_SC;
2390 if (hci_dev_test_flag(hcon->hdev, HCI_SSP_ENABLED))
2391 authreq |= SMP_AUTH_CT2;
2392 }
2393
2394 /* Require MITM if IO Capability allows or the security level
2395 * requires it.
2396 */
2397 if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT ||
2398 hcon->pending_sec_level > BT_SECURITY_MEDIUM)
2399 authreq |= SMP_AUTH_MITM;
2400
2401 if (hcon->role == HCI_ROLE_MASTER) {
2402 struct smp_cmd_pairing cp;
2403
2404 build_pairing_cmd(conn, &cp, NULL, authreq);
2405 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2406 memcpy(&smp->preq[1], &cp, sizeof(cp));
2407
2408 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2409 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2410 } else {
2411 struct smp_cmd_security_req cp;
2412 cp.auth_req = authreq;
2413 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
2414 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ);
2415 }
2416
2417 set_bit(SMP_FLAG_INITIATOR, &smp->flags);
2418 ret = 0;
2419
2420 unlock:
2421 l2cap_chan_unlock(chan);
2422 return ret;
2423 }
2424
2425 int smp_cancel_and_remove_pairing(struct hci_dev *hdev, bdaddr_t *bdaddr,
2426 u8 addr_type)
2427 {
2428 struct hci_conn *hcon;
2429 struct l2cap_conn *conn;
2430 struct l2cap_chan *chan;
2431 struct smp_chan *smp;
2432 int err;
2433
2434 err = hci_remove_ltk(hdev, bdaddr, addr_type);
2435 hci_remove_irk(hdev, bdaddr, addr_type);
2436
2437 hcon = hci_conn_hash_lookup_le(hdev, bdaddr, addr_type);
2438 if (!hcon)
2439 goto done;
2440
2441 conn = hcon->l2cap_data;
2442 if (!conn)
2443 goto done;
2444
2445 chan = conn->smp;
2446 if (!chan)
2447 goto done;
2448
2449 l2cap_chan_lock(chan);
2450
2451 smp = chan->data;
2452 if (smp) {
2453 /* Set keys to NULL to make sure smp_failure() does not try to
2454 * remove and free already invalidated rcu list entries. */
2455 smp->ltk = NULL;
2456 smp->slave_ltk = NULL;
2457 smp->remote_irk = NULL;
2458
2459 if (test_bit(SMP_FLAG_COMPLETE, &smp->flags))
2460 smp_failure(conn, 0);
2461 else
2462 smp_failure(conn, SMP_UNSPECIFIED);
2463 err = 0;
2464 }
2465
2466 l2cap_chan_unlock(chan);
2467
2468 done:
2469 return err;
2470 }
2471
2472 static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb)
2473 {
2474 struct smp_cmd_encrypt_info *rp = (void *) skb->data;
2475 struct l2cap_chan *chan = conn->smp;
2476 struct smp_chan *smp = chan->data;
2477
2478 BT_DBG("conn %p", conn);
2479
2480 if (skb->len < sizeof(*rp))
2481 return SMP_INVALID_PARAMS;
2482
2483 SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT);
2484
2485 skb_pull(skb, sizeof(*rp));
2486
2487 memcpy(smp->tk, rp->ltk, sizeof(smp->tk));
2488
2489 return 0;
2490 }
2491
2492 static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
2493 {
2494 struct smp_cmd_master_ident *rp = (void *) skb->data;
2495 struct l2cap_chan *chan = conn->smp;
2496 struct smp_chan *smp = chan->data;
2497 struct hci_dev *hdev = conn->hcon->hdev;
2498 struct hci_conn *hcon = conn->hcon;
2499 struct smp_ltk *ltk;
2500 u8 authenticated;
2501
2502 BT_DBG("conn %p", conn);
2503
2504 if (skb->len < sizeof(*rp))
2505 return SMP_INVALID_PARAMS;
2506
2507 /* Mark the information as received */
2508 smp->remote_key_dist &= ~SMP_DIST_ENC_KEY;
2509
2510 if (smp->remote_key_dist & SMP_DIST_ID_KEY)
2511 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
2512 else if (smp->remote_key_dist & SMP_DIST_SIGN)
2513 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2514
2515 skb_pull(skb, sizeof(*rp));
2516
2517 authenticated = (hcon->sec_level == BT_SECURITY_HIGH);
2518 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK,
2519 authenticated, smp->tk, smp->enc_key_size,
2520 rp->ediv, rp->rand);
2521 smp->ltk = ltk;
2522 if (!(smp->remote_key_dist & KEY_DIST_MASK))
2523 smp_distribute_keys(smp);
2524
2525 return 0;
2526 }
2527
2528 static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb)
2529 {
2530 struct smp_cmd_ident_info *info = (void *) skb->data;
2531 struct l2cap_chan *chan = conn->smp;
2532 struct smp_chan *smp = chan->data;
2533
2534 BT_DBG("");
2535
2536 if (skb->len < sizeof(*info))
2537 return SMP_INVALID_PARAMS;
2538
2539 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO);
2540
2541 skb_pull(skb, sizeof(*info));
2542
2543 memcpy(smp->irk, info->irk, 16);
2544
2545 return 0;
2546 }
2547
2548 static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,
2549 struct sk_buff *skb)
2550 {
2551 struct smp_cmd_ident_addr_info *info = (void *) skb->data;
2552 struct l2cap_chan *chan = conn->smp;
2553 struct smp_chan *smp = chan->data;
2554 struct hci_conn *hcon = conn->hcon;
2555 bdaddr_t rpa;
2556
2557 BT_DBG("");
2558
2559 if (skb->len < sizeof(*info))
2560 return SMP_INVALID_PARAMS;
2561
2562 /* Mark the information as received */
2563 smp->remote_key_dist &= ~SMP_DIST_ID_KEY;
2564
2565 if (smp->remote_key_dist & SMP_DIST_SIGN)
2566 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2567
2568 skb_pull(skb, sizeof(*info));
2569
2570 /* Strictly speaking the Core Specification (4.1) allows sending
2571 * an empty address which would force us to rely on just the IRK
2572 * as "identity information". However, since such
2573 * implementations are not known of and in order to not over
2574 * complicate our implementation, simply pretend that we never
2575 * received an IRK for such a device.
2576 *
2577 * The Identity Address must also be a Static Random or Public
2578 * Address, which hci_is_identity_address() checks for.
2579 */
2580 if (!bacmp(&info->bdaddr, BDADDR_ANY) ||
2581 !hci_is_identity_address(&info->bdaddr, info->addr_type)) {
2582 bt_dev_err(hcon->hdev, "ignoring IRK with no identity address");
2583 goto distribute;
2584 }
2585
2586 bacpy(&smp->id_addr, &info->bdaddr);
2587 smp->id_addr_type = info->addr_type;
2588
2589 if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type))
2590 bacpy(&rpa, &hcon->dst);
2591 else
2592 bacpy(&rpa, BDADDR_ANY);
2593
2594 smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr,
2595 smp->id_addr_type, smp->irk, &rpa);
2596
2597 distribute:
2598 if (!(smp->remote_key_dist & KEY_DIST_MASK))
2599 smp_distribute_keys(smp);
2600
2601 return 0;
2602 }
2603
2604 static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb)
2605 {
2606 struct smp_cmd_sign_info *rp = (void *) skb->data;
2607 struct l2cap_chan *chan = conn->smp;
2608 struct smp_chan *smp = chan->data;
2609 struct smp_csrk *csrk;
2610
2611 BT_DBG("conn %p", conn);
2612
2613 if (skb->len < sizeof(*rp))
2614 return SMP_INVALID_PARAMS;
2615
2616 /* Mark the information as received */
2617 smp->remote_key_dist &= ~SMP_DIST_SIGN;
2618
2619 skb_pull(skb, sizeof(*rp));
2620
2621 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
2622 if (csrk) {
2623 if (conn->hcon->sec_level > BT_SECURITY_MEDIUM)
2624 csrk->type = MGMT_CSRK_REMOTE_AUTHENTICATED;
2625 else
2626 csrk->type = MGMT_CSRK_REMOTE_UNAUTHENTICATED;
2627 memcpy(csrk->val, rp->csrk, sizeof(csrk->val));
2628 }
2629 smp->csrk = csrk;
2630 smp_distribute_keys(smp);
2631
2632 return 0;
2633 }
2634
2635 static u8 sc_select_method(struct smp_chan *smp)
2636 {
2637 struct l2cap_conn *conn = smp->conn;
2638 struct hci_conn *hcon = conn->hcon;
2639 struct smp_cmd_pairing *local, *remote;
2640 u8 local_mitm, remote_mitm, local_io, remote_io, method;
2641
2642 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags) ||
2643 test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags))
2644 return REQ_OOB;
2645
2646 /* The preq/prsp contain the raw Pairing Request/Response PDUs
2647 * which are needed as inputs to some crypto functions. To get
2648 * the "struct smp_cmd_pairing" from them we need to skip the
2649 * first byte which contains the opcode.
2650 */
2651 if (hcon->out) {
2652 local = (void *) &smp->preq[1];
2653 remote = (void *) &smp->prsp[1];
2654 } else {
2655 local = (void *) &smp->prsp[1];
2656 remote = (void *) &smp->preq[1];
2657 }
2658
2659 local_io = local->io_capability;
2660 remote_io = remote->io_capability;
2661
2662 local_mitm = (local->auth_req & SMP_AUTH_MITM);
2663 remote_mitm = (remote->auth_req & SMP_AUTH_MITM);
2664
2665 /* If either side wants MITM, look up the method from the table,
2666 * otherwise use JUST WORKS.
2667 */
2668 if (local_mitm || remote_mitm)
2669 method = get_auth_method(smp, local_io, remote_io);
2670 else
2671 method = JUST_WORKS;
2672
2673 /* Don't confirm locally initiated pairing attempts */
2674 if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags))
2675 method = JUST_WORKS;
2676
2677 return method;
2678 }
2679
2680 static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb)
2681 {
2682 struct smp_cmd_public_key *key = (void *) skb->data;
2683 struct hci_conn *hcon = conn->hcon;
2684 struct l2cap_chan *chan = conn->smp;
2685 struct smp_chan *smp = chan->data;
2686 struct hci_dev *hdev = hcon->hdev;
2687 struct crypto_kpp *tfm_ecdh;
2688 struct smp_cmd_pairing_confirm cfm;
2689 int err;
2690
2691 BT_DBG("conn %p", conn);
2692
2693 if (skb->len < sizeof(*key))
2694 return SMP_INVALID_PARAMS;
2695
2696 memcpy(smp->remote_pk, key, 64);
2697
2698 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags)) {
2699 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk,
2700 smp->rr, 0, cfm.confirm_val);
2701 if (err)
2702 return SMP_UNSPECIFIED;
2703
2704 if (crypto_memneq(cfm.confirm_val, smp->pcnf, 16))
2705 return SMP_CONFIRM_FAILED;
2706 }
2707
2708 /* Non-initiating device sends its public key after receiving
2709 * the key from the initiating device.
2710 */
2711 if (!hcon->out) {
2712 err = sc_send_public_key(smp);
2713 if (err)
2714 return err;
2715 }
2716
2717 SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk);
2718 SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32);
2719
2720 /* Compute the shared secret on the same crypto tfm on which the private
2721 * key was set/generated.
2722 */
2723 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) {
2724 struct l2cap_chan *hchan = hdev->smp_data;
2725 struct smp_dev *smp_dev;
2726
2727 if (!hchan || !hchan->data)
2728 return SMP_UNSPECIFIED;
2729
2730 smp_dev = hchan->data;
2731
2732 tfm_ecdh = smp_dev->tfm_ecdh;
2733 } else {
2734 tfm_ecdh = smp->tfm_ecdh;
2735 }
2736
2737 if (compute_ecdh_secret(tfm_ecdh, smp->remote_pk, smp->dhkey))
2738 return SMP_UNSPECIFIED;
2739
2740 SMP_DBG("DHKey %32phN", smp->dhkey);
2741
2742 set_bit(SMP_FLAG_REMOTE_PK, &smp->flags);
2743
2744 smp->method = sc_select_method(smp);
2745
2746 BT_DBG("%s selected method 0x%02x", hdev->name, smp->method);
2747
2748 /* JUST_WORKS and JUST_CFM result in an unauthenticated key */
2749 if (smp->method == JUST_WORKS || smp->method == JUST_CFM)
2750 hcon->pending_sec_level = BT_SECURITY_MEDIUM;
2751 else
2752 hcon->pending_sec_level = BT_SECURITY_FIPS;
2753
2754 if (!crypto_memneq(debug_pk, smp->remote_pk, 64))
2755 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
2756
2757 if (smp->method == DSP_PASSKEY) {
2758 get_random_bytes(&hcon->passkey_notify,
2759 sizeof(hcon->passkey_notify));
2760 hcon->passkey_notify %= 1000000;
2761 hcon->passkey_entered = 0;
2762 smp->passkey_round = 0;
2763 if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type,
2764 hcon->dst_type,
2765 hcon->passkey_notify,
2766 hcon->passkey_entered))
2767 return SMP_UNSPECIFIED;
2768 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2769 return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY);
2770 }
2771
2772 if (smp->method == REQ_OOB) {
2773 if (hcon->out)
2774 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2775 sizeof(smp->prnd), smp->prnd);
2776
2777 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2778
2779 return 0;
2780 }
2781
2782 if (hcon->out)
2783 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2784
2785 if (smp->method == REQ_PASSKEY) {
2786 if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type,
2787 hcon->dst_type))
2788 return SMP_UNSPECIFIED;
2789 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2790 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2791 return 0;
2792 }
2793
2794 /* The Initiating device waits for the non-initiating device to
2795 * send the confirm value.
2796 */
2797 if (conn->hcon->out)
2798 return 0;
2799
2800 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd,
2801 0, cfm.confirm_val);
2802 if (err)
2803 return SMP_UNSPECIFIED;
2804
2805 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
2806 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2807
2808 return 0;
2809 }
2810
2811 static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb)
2812 {
2813 struct smp_cmd_dhkey_check *check = (void *) skb->data;
2814 struct l2cap_chan *chan = conn->smp;
2815 struct hci_conn *hcon = conn->hcon;
2816 struct smp_chan *smp = chan->data;
2817 u8 a[7], b[7], *local_addr, *remote_addr;
2818 u8 io_cap[3], r[16], e[16];
2819 int err;
2820
2821 BT_DBG("conn %p", conn);
2822
2823 if (skb->len < sizeof(*check))
2824 return SMP_INVALID_PARAMS;
2825
2826 memcpy(a, &hcon->init_addr, 6);
2827 memcpy(b, &hcon->resp_addr, 6);
2828 a[6] = hcon->init_addr_type;
2829 b[6] = hcon->resp_addr_type;
2830
2831 if (hcon->out) {
2832 local_addr = a;
2833 remote_addr = b;
2834 memcpy(io_cap, &smp->prsp[1], 3);
2835 } else {
2836 local_addr = b;
2837 remote_addr = a;
2838 memcpy(io_cap, &smp->preq[1], 3);
2839 }
2840
2841 memset(r, 0, sizeof(r));
2842
2843 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2844 put_unaligned_le32(hcon->passkey_notify, r);
2845 else if (smp->method == REQ_OOB)
2846 memcpy(r, smp->lr, 16);
2847
2848 err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r,
2849 io_cap, remote_addr, local_addr, e);
2850 if (err)
2851 return SMP_UNSPECIFIED;
2852
2853 if (crypto_memneq(check->e, e, 16))
2854 return SMP_DHKEY_CHECK_FAILED;
2855
2856 if (!hcon->out) {
2857 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
2858 set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags);
2859 return 0;
2860 }
2861
2862 /* Slave sends DHKey check as response to master */
2863 sc_dhkey_check(smp);
2864 }
2865
2866 sc_add_ltk(smp);
2867
2868 if (hcon->out) {
2869 hci_le_start_enc(hcon, 0, 0, smp->tk, smp->enc_key_size);
2870 hcon->enc_key_size = smp->enc_key_size;
2871 }
2872
2873 return 0;
2874 }
2875
2876 static int smp_cmd_keypress_notify(struct l2cap_conn *conn,
2877 struct sk_buff *skb)
2878 {
2879 struct smp_cmd_keypress_notify *kp = (void *) skb->data;
2880
2881 BT_DBG("value 0x%02x", kp->value);
2882
2883 return 0;
2884 }
2885
2886 static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb)
2887 {
2888 struct l2cap_conn *conn = chan->conn;
2889 struct hci_conn *hcon = conn->hcon;
2890 struct smp_chan *smp;
2891 __u8 code, reason;
2892 int err = 0;
2893
2894 if (skb->len < 1)
2895 return -EILSEQ;
2896
2897 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) {
2898 reason = SMP_PAIRING_NOTSUPP;
2899 goto done;
2900 }
2901
2902 code = skb->data[0];
2903 skb_pull(skb, sizeof(code));
2904
2905 smp = chan->data;
2906
2907 if (code > SMP_CMD_MAX)
2908 goto drop;
2909
2910 if (smp && !test_and_clear_bit(code, &smp->allow_cmd))
2911 goto drop;
2912
2913 /* If we don't have a context the only allowed commands are
2914 * pairing request and security request.
2915 */
2916 if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ)
2917 goto drop;
2918
2919 switch (code) {
2920 case SMP_CMD_PAIRING_REQ:
2921 reason = smp_cmd_pairing_req(conn, skb);
2922 break;
2923
2924 case SMP_CMD_PAIRING_FAIL:
2925 smp_failure(conn, 0);
2926 err = -EPERM;
2927 break;
2928
2929 case SMP_CMD_PAIRING_RSP:
2930 reason = smp_cmd_pairing_rsp(conn, skb);
2931 break;
2932
2933 case SMP_CMD_SECURITY_REQ:
2934 reason = smp_cmd_security_req(conn, skb);
2935 break;
2936
2937 case SMP_CMD_PAIRING_CONFIRM:
2938 reason = smp_cmd_pairing_confirm(conn, skb);
2939 break;
2940
2941 case SMP_CMD_PAIRING_RANDOM:
2942 reason = smp_cmd_pairing_random(conn, skb);
2943 break;
2944
2945 case SMP_CMD_ENCRYPT_INFO:
2946 reason = smp_cmd_encrypt_info(conn, skb);
2947 break;
2948
2949 case SMP_CMD_MASTER_IDENT:
2950 reason = smp_cmd_master_ident(conn, skb);
2951 break;
2952
2953 case SMP_CMD_IDENT_INFO:
2954 reason = smp_cmd_ident_info(conn, skb);
2955 break;
2956
2957 case SMP_CMD_IDENT_ADDR_INFO:
2958 reason = smp_cmd_ident_addr_info(conn, skb);
2959 break;
2960
2961 case SMP_CMD_SIGN_INFO:
2962 reason = smp_cmd_sign_info(conn, skb);
2963 break;
2964
2965 case SMP_CMD_PUBLIC_KEY:
2966 reason = smp_cmd_public_key(conn, skb);
2967 break;
2968
2969 case SMP_CMD_DHKEY_CHECK:
2970 reason = smp_cmd_dhkey_check(conn, skb);
2971 break;
2972
2973 case SMP_CMD_KEYPRESS_NOTIFY:
2974 reason = smp_cmd_keypress_notify(conn, skb);
2975 break;
2976
2977 default:
2978 BT_DBG("Unknown command code 0x%2.2x", code);
2979 reason = SMP_CMD_NOTSUPP;
2980 goto done;
2981 }
2982
2983 done:
2984 if (!err) {
2985 if (reason)
2986 smp_failure(conn, reason);
2987 kfree_skb(skb);
2988 }
2989
2990 return err;
2991
2992 drop:
2993 bt_dev_err(hcon->hdev, "unexpected SMP command 0x%02x from %pMR",
2994 code, &hcon->dst);
2995 kfree_skb(skb);
2996 return 0;
2997 }
2998
2999 static void smp_teardown_cb(struct l2cap_chan *chan, int err)
3000 {
3001 struct l2cap_conn *conn = chan->conn;
3002
3003 BT_DBG("chan %p", chan);
3004
3005 if (chan->data)
3006 smp_chan_destroy(conn);
3007
3008 conn->smp = NULL;
3009 l2cap_chan_put(chan);
3010 }
3011
3012 static void bredr_pairing(struct l2cap_chan *chan)
3013 {
3014 struct l2cap_conn *conn = chan->conn;
3015 struct hci_conn *hcon = conn->hcon;
3016 struct hci_dev *hdev = hcon->hdev;
3017 struct smp_cmd_pairing req;
3018 struct smp_chan *smp;
3019
3020 BT_DBG("chan %p", chan);
3021
3022 /* Only new pairings are interesting */
3023 if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags))
3024 return;
3025
3026 /* Don't bother if we're not encrypted */
3027 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
3028 return;
3029
3030 /* Only master may initiate SMP over BR/EDR */
3031 if (hcon->role != HCI_ROLE_MASTER)
3032 return;
3033
3034 /* Secure Connections support must be enabled */
3035 if (!hci_dev_test_flag(hdev, HCI_SC_ENABLED))
3036 return;
3037
3038 /* BR/EDR must use Secure Connections for SMP */
3039 if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) &&
3040 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3041 return;
3042
3043 /* If our LE support is not enabled don't do anything */
3044 if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED))
3045 return;
3046
3047 /* Don't bother if remote LE support is not enabled */
3048 if (!lmp_host_le_capable(hcon))
3049 return;
3050
3051 /* Remote must support SMP fixed chan for BR/EDR */
3052 if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR))
3053 return;
3054
3055 /* Don't bother if SMP is already ongoing */
3056 if (chan->data)
3057 return;
3058
3059 smp = smp_chan_create(conn);
3060 if (!smp) {
3061 bt_dev_err(hdev, "unable to create SMP context for BR/EDR");
3062 return;
3063 }
3064
3065 set_bit(SMP_FLAG_SC, &smp->flags);
3066
3067 BT_DBG("%s starting SMP over BR/EDR", hdev->name);
3068
3069 /* Prepare and send the BR/EDR SMP Pairing Request */
3070 build_bredr_pairing_cmd(smp, &req, NULL);
3071
3072 smp->preq[0] = SMP_CMD_PAIRING_REQ;
3073 memcpy(&smp->preq[1], &req, sizeof(req));
3074
3075 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req);
3076 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
3077 }
3078
3079 static void smp_resume_cb(struct l2cap_chan *chan)
3080 {
3081 struct smp_chan *smp = chan->data;
3082 struct l2cap_conn *conn = chan->conn;
3083 struct hci_conn *hcon = conn->hcon;
3084
3085 BT_DBG("chan %p", chan);
3086
3087 if (hcon->type == ACL_LINK) {
3088 bredr_pairing(chan);
3089 return;
3090 }
3091
3092 if (!smp)
3093 return;
3094
3095 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
3096 return;
3097
3098 cancel_delayed_work(&smp->security_timer);
3099
3100 smp_distribute_keys(smp);
3101 }
3102
3103 static void smp_ready_cb(struct l2cap_chan *chan)
3104 {
3105 struct l2cap_conn *conn = chan->conn;
3106 struct hci_conn *hcon = conn->hcon;
3107
3108 BT_DBG("chan %p", chan);
3109
3110 /* No need to call l2cap_chan_hold() here since we already own
3111 * the reference taken in smp_new_conn_cb(). This is just the
3112 * first time that we tie it to a specific pointer. The code in
3113 * l2cap_core.c ensures that there's no risk this function wont
3114 * get called if smp_new_conn_cb was previously called.
3115 */
3116 conn->smp = chan;
3117
3118 if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
3119 bredr_pairing(chan);
3120 }
3121
3122 static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
3123 {
3124 int err;
3125
3126 BT_DBG("chan %p", chan);
3127
3128 err = smp_sig_channel(chan, skb);
3129 if (err) {
3130 struct smp_chan *smp = chan->data;
3131
3132 if (smp)
3133 cancel_delayed_work_sync(&smp->security_timer);
3134
3135 hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE);
3136 }
3137
3138 return err;
3139 }
3140
3141 static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan,
3142 unsigned long hdr_len,
3143 unsigned long len, int nb)
3144 {
3145 struct sk_buff *skb;
3146
3147 skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL);
3148 if (!skb)
3149 return ERR_PTR(-ENOMEM);
3150
3151 skb->priority = HCI_PRIO_MAX;
3152 bt_cb(skb)->l2cap.chan = chan;
3153
3154 return skb;
3155 }
3156
3157 static const struct l2cap_ops smp_chan_ops = {
3158 .name = "Security Manager",
3159 .ready = smp_ready_cb,
3160 .recv = smp_recv_cb,
3161 .alloc_skb = smp_alloc_skb_cb,
3162 .teardown = smp_teardown_cb,
3163 .resume = smp_resume_cb,
3164
3165 .new_connection = l2cap_chan_no_new_connection,
3166 .state_change = l2cap_chan_no_state_change,
3167 .close = l2cap_chan_no_close,
3168 .defer = l2cap_chan_no_defer,
3169 .suspend = l2cap_chan_no_suspend,
3170 .set_shutdown = l2cap_chan_no_set_shutdown,
3171 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
3172 };
3173
3174 static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan)
3175 {
3176 struct l2cap_chan *chan;
3177
3178 BT_DBG("pchan %p", pchan);
3179
3180 chan = l2cap_chan_create();
3181 if (!chan)
3182 return NULL;
3183
3184 chan->chan_type = pchan->chan_type;
3185 chan->ops = &smp_chan_ops;
3186 chan->scid = pchan->scid;
3187 chan->dcid = chan->scid;
3188 chan->imtu = pchan->imtu;
3189 chan->omtu = pchan->omtu;
3190 chan->mode = pchan->mode;
3191
3192 /* Other L2CAP channels may request SMP routines in order to
3193 * change the security level. This means that the SMP channel
3194 * lock must be considered in its own category to avoid lockdep
3195 * warnings.
3196 */
3197 atomic_set(&chan->nesting, L2CAP_NESTING_SMP);
3198
3199 BT_DBG("created chan %p", chan);
3200
3201 return chan;
3202 }
3203
3204 static const struct l2cap_ops smp_root_chan_ops = {
3205 .name = "Security Manager Root",
3206 .new_connection = smp_new_conn_cb,
3207
3208 /* None of these are implemented for the root channel */
3209 .close = l2cap_chan_no_close,
3210 .alloc_skb = l2cap_chan_no_alloc_skb,
3211 .recv = l2cap_chan_no_recv,
3212 .state_change = l2cap_chan_no_state_change,
3213 .teardown = l2cap_chan_no_teardown,
3214 .ready = l2cap_chan_no_ready,
3215 .defer = l2cap_chan_no_defer,
3216 .suspend = l2cap_chan_no_suspend,
3217 .resume = l2cap_chan_no_resume,
3218 .set_shutdown = l2cap_chan_no_set_shutdown,
3219 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
3220 };
3221
3222 static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid)
3223 {
3224 struct l2cap_chan *chan;
3225 struct smp_dev *smp;
3226 struct crypto_cipher *tfm_aes;
3227 struct crypto_shash *tfm_cmac;
3228 struct crypto_kpp *tfm_ecdh;
3229
3230 if (cid == L2CAP_CID_SMP_BREDR) {
3231 smp = NULL;
3232 goto create_chan;
3233 }
3234
3235 smp = kzalloc(sizeof(*smp), GFP_KERNEL);
3236 if (!smp)
3237 return ERR_PTR(-ENOMEM);
3238
3239 tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
3240 if (IS_ERR(tfm_aes)) {
3241 BT_ERR("Unable to create AES crypto context");
3242 kzfree(smp);
3243 return ERR_CAST(tfm_aes);
3244 }
3245
3246 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
3247 if (IS_ERR(tfm_cmac)) {
3248 BT_ERR("Unable to create CMAC crypto context");
3249 crypto_free_cipher(tfm_aes);
3250 kzfree(smp);
3251 return ERR_CAST(tfm_cmac);
3252 }
3253
3254 tfm_ecdh = crypto_alloc_kpp("ecdh", CRYPTO_ALG_INTERNAL, 0);
3255 if (IS_ERR(tfm_ecdh)) {
3256 BT_ERR("Unable to create ECDH crypto context");
3257 crypto_free_shash(tfm_cmac);
3258 crypto_free_cipher(tfm_aes);
3259 kzfree(smp);
3260 return ERR_CAST(tfm_ecdh);
3261 }
3262
3263 smp->local_oob = false;
3264 smp->tfm_aes = tfm_aes;
3265 smp->tfm_cmac = tfm_cmac;
3266 smp->tfm_ecdh = tfm_ecdh;
3267 smp->min_key_size = SMP_MIN_ENC_KEY_SIZE;
3268 smp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
3269
3270 create_chan:
3271 chan = l2cap_chan_create();
3272 if (!chan) {
3273 if (smp) {
3274 crypto_free_cipher(smp->tfm_aes);
3275 crypto_free_shash(smp->tfm_cmac);
3276 crypto_free_kpp(smp->tfm_ecdh);
3277 kzfree(smp);
3278 }
3279 return ERR_PTR(-ENOMEM);
3280 }
3281
3282 chan->data = smp;
3283
3284 l2cap_add_scid(chan, cid);
3285
3286 l2cap_chan_set_defaults(chan);
3287
3288 if (cid == L2CAP_CID_SMP) {
3289 u8 bdaddr_type;
3290
3291 hci_copy_identity_address(hdev, &chan->src, &bdaddr_type);
3292
3293 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
3294 chan->src_type = BDADDR_LE_PUBLIC;
3295 else
3296 chan->src_type = BDADDR_LE_RANDOM;
3297 } else {
3298 bacpy(&chan->src, &hdev->bdaddr);
3299 chan->src_type = BDADDR_BREDR;
3300 }
3301
3302 chan->state = BT_LISTEN;
3303 chan->mode = L2CAP_MODE_BASIC;
3304 chan->imtu = L2CAP_DEFAULT_MTU;
3305 chan->ops = &smp_root_chan_ops;
3306
3307 /* Set correct nesting level for a parent/listening channel */
3308 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
3309
3310 return chan;
3311 }
3312
3313 static void smp_del_chan(struct l2cap_chan *chan)
3314 {
3315 struct smp_dev *smp;
3316
3317 BT_DBG("chan %p", chan);
3318
3319 smp = chan->data;
3320 if (smp) {
3321 chan->data = NULL;
3322 crypto_free_cipher(smp->tfm_aes);
3323 crypto_free_shash(smp->tfm_cmac);
3324 crypto_free_kpp(smp->tfm_ecdh);
3325 kzfree(smp);
3326 }
3327
3328 l2cap_chan_put(chan);
3329 }
3330
3331 static ssize_t force_bredr_smp_read(struct file *file,
3332 char __user *user_buf,
3333 size_t count, loff_t *ppos)
3334 {
3335 struct hci_dev *hdev = file->private_data;
3336 char buf[3];
3337
3338 buf[0] = hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP) ? 'Y': 'N';
3339 buf[1] = '\n';
3340 buf[2] = '\0';
3341 return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
3342 }
3343
3344 static ssize_t force_bredr_smp_write(struct file *file,
3345 const char __user *user_buf,
3346 size_t count, loff_t *ppos)
3347 {
3348 struct hci_dev *hdev = file->private_data;
3349 char buf[32];
3350 size_t buf_size = min(count, (sizeof(buf)-1));
3351 bool enable;
3352
3353 if (copy_from_user(buf, user_buf, buf_size))
3354 return -EFAULT;
3355
3356 buf[buf_size] = '\0';
3357 if (strtobool(buf, &enable))
3358 return -EINVAL;
3359
3360 if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3361 return -EALREADY;
3362
3363 if (enable) {
3364 struct l2cap_chan *chan;
3365
3366 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3367 if (IS_ERR(chan))
3368 return PTR_ERR(chan);
3369
3370 hdev->smp_bredr_data = chan;
3371 } else {
3372 struct l2cap_chan *chan;
3373
3374 chan = hdev->smp_bredr_data;
3375 hdev->smp_bredr_data = NULL;
3376 smp_del_chan(chan);
3377 }
3378
3379 hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP);
3380
3381 return count;
3382 }
3383
3384 static const struct file_operations force_bredr_smp_fops = {
3385 .open = simple_open,
3386 .read = force_bredr_smp_read,
3387 .write = force_bredr_smp_write,
3388 .llseek = default_llseek,
3389 };
3390
3391 static ssize_t le_min_key_size_read(struct file *file,
3392 char __user *user_buf,
3393 size_t count, loff_t *ppos)
3394 {
3395 struct hci_dev *hdev = file->private_data;
3396 char buf[4];
3397
3398 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->min_key_size);
3399
3400 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf));
3401 }
3402
3403 static ssize_t le_min_key_size_write(struct file *file,
3404 const char __user *user_buf,
3405 size_t count, loff_t *ppos)
3406 {
3407 struct hci_dev *hdev = file->private_data;
3408 char buf[32];
3409 size_t buf_size = min(count, (sizeof(buf) - 1));
3410 u8 key_size;
3411
3412 if (copy_from_user(buf, user_buf, buf_size))
3413 return -EFAULT;
3414
3415 buf[buf_size] = '\0';
3416
3417 sscanf(buf, "%hhu", &key_size);
3418
3419 if (key_size > SMP_DEV(hdev)->max_key_size ||
3420 key_size < SMP_MIN_ENC_KEY_SIZE)
3421 return -EINVAL;
3422
3423 SMP_DEV(hdev)->min_key_size = key_size;
3424
3425 return count;
3426 }
3427
3428 static const struct file_operations le_min_key_size_fops = {
3429 .open = simple_open,
3430 .read = le_min_key_size_read,
3431 .write = le_min_key_size_write,
3432 .llseek = default_llseek,
3433 };
3434
3435 static ssize_t le_max_key_size_read(struct file *file,
3436 char __user *user_buf,
3437 size_t count, loff_t *ppos)
3438 {
3439 struct hci_dev *hdev = file->private_data;
3440 char buf[4];
3441
3442 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->max_key_size);
3443
3444 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf));
3445 }
3446
3447 static ssize_t le_max_key_size_write(struct file *file,
3448 const char __user *user_buf,
3449 size_t count, loff_t *ppos)
3450 {
3451 struct hci_dev *hdev = file->private_data;
3452 char buf[32];
3453 size_t buf_size = min(count, (sizeof(buf) - 1));
3454 u8 key_size;
3455
3456 if (copy_from_user(buf, user_buf, buf_size))
3457 return -EFAULT;
3458
3459 buf[buf_size] = '\0';
3460
3461 sscanf(buf, "%hhu", &key_size);
3462
3463 if (key_size > SMP_MAX_ENC_KEY_SIZE ||
3464 key_size < SMP_DEV(hdev)->min_key_size)
3465 return -EINVAL;
3466
3467 SMP_DEV(hdev)->max_key_size = key_size;
3468
3469 return count;
3470 }
3471
3472 static const struct file_operations le_max_key_size_fops = {
3473 .open = simple_open,
3474 .read = le_max_key_size_read,
3475 .write = le_max_key_size_write,
3476 .llseek = default_llseek,
3477 };
3478
3479 int smp_register(struct hci_dev *hdev)
3480 {
3481 struct l2cap_chan *chan;
3482
3483 BT_DBG("%s", hdev->name);
3484
3485 /* If the controller does not support Low Energy operation, then
3486 * there is also no need to register any SMP channel.
3487 */
3488 if (!lmp_le_capable(hdev))
3489 return 0;
3490
3491 if (WARN_ON(hdev->smp_data)) {
3492 chan = hdev->smp_data;
3493 hdev->smp_data = NULL;
3494 smp_del_chan(chan);
3495 }
3496
3497 chan = smp_add_cid(hdev, L2CAP_CID_SMP);
3498 if (IS_ERR(chan))
3499 return PTR_ERR(chan);
3500
3501 hdev->smp_data = chan;
3502
3503 debugfs_create_file("le_min_key_size", 0644, hdev->debugfs, hdev,
3504 &le_min_key_size_fops);
3505 debugfs_create_file("le_max_key_size", 0644, hdev->debugfs, hdev,
3506 &le_max_key_size_fops);
3507
3508 /* If the controller does not support BR/EDR Secure Connections
3509 * feature, then the BR/EDR SMP channel shall not be present.
3510 *
3511 * To test this with Bluetooth 4.0 controllers, create a debugfs
3512 * switch that allows forcing BR/EDR SMP support and accepting
3513 * cross-transport pairing on non-AES encrypted connections.
3514 */
3515 if (!lmp_sc_capable(hdev)) {
3516 debugfs_create_file("force_bredr_smp", 0644, hdev->debugfs,
3517 hdev, &force_bredr_smp_fops);
3518
3519 /* Flag can be already set here (due to power toggle) */
3520 if (!hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3521 return 0;
3522 }
3523
3524 if (WARN_ON(hdev->smp_bredr_data)) {
3525 chan = hdev->smp_bredr_data;
3526 hdev->smp_bredr_data = NULL;
3527 smp_del_chan(chan);
3528 }
3529
3530 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3531 if (IS_ERR(chan)) {
3532 int err = PTR_ERR(chan);
3533 chan = hdev->smp_data;
3534 hdev->smp_data = NULL;
3535 smp_del_chan(chan);
3536 return err;
3537 }
3538
3539 hdev->smp_bredr_data = chan;
3540
3541 return 0;
3542 }
3543
3544 void smp_unregister(struct hci_dev *hdev)
3545 {
3546 struct l2cap_chan *chan;
3547
3548 if (hdev->smp_bredr_data) {
3549 chan = hdev->smp_bredr_data;
3550 hdev->smp_bredr_data = NULL;
3551 smp_del_chan(chan);
3552 }
3553
3554 if (hdev->smp_data) {
3555 chan = hdev->smp_data;
3556 hdev->smp_data = NULL;
3557 smp_del_chan(chan);
3558 }
3559 }
3560
3561 #if IS_ENABLED(CONFIG_BT_SELFTEST_SMP)
3562
3563 static int __init test_debug_key(struct crypto_kpp *tfm_ecdh)
3564 {
3565 u8 pk[64];
3566 int err;
3567
3568 err = set_ecdh_privkey(tfm_ecdh, debug_sk);
3569 if (err)
3570 return err;
3571
3572 err = generate_ecdh_public_key(tfm_ecdh, pk);
3573 if (err)
3574 return err;
3575
3576 if (crypto_memneq(pk, debug_pk, 64))
3577 return -EINVAL;
3578
3579 return 0;
3580 }
3581
3582 static int __init test_ah(struct crypto_cipher *tfm_aes)
3583 {
3584 const u8 irk[16] = {
3585 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3586 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3587 const u8 r[3] = { 0x94, 0x81, 0x70 };
3588 const u8 exp[3] = { 0xaa, 0xfb, 0x0d };
3589 u8 res[3];
3590 int err;
3591
3592 err = smp_ah(tfm_aes, irk, r, res);
3593 if (err)
3594 return err;
3595
3596 if (crypto_memneq(res, exp, 3))
3597 return -EINVAL;
3598
3599 return 0;
3600 }
3601
3602 static int __init test_c1(struct crypto_cipher *tfm_aes)
3603 {
3604 const u8 k[16] = {
3605 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
3606 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
3607 const u8 r[16] = {
3608 0xe0, 0x2e, 0x70, 0xc6, 0x4e, 0x27, 0x88, 0x63,
3609 0x0e, 0x6f, 0xad, 0x56, 0x21, 0xd5, 0x83, 0x57 };
3610 const u8 preq[7] = { 0x01, 0x01, 0x00, 0x00, 0x10, 0x07, 0x07 };
3611 const u8 pres[7] = { 0x02, 0x03, 0x00, 0x00, 0x08, 0x00, 0x05 };
3612 const u8 _iat = 0x01;
3613 const u8 _rat = 0x00;
3614 const bdaddr_t ra = { { 0xb6, 0xb5, 0xb4, 0xb3, 0xb2, 0xb1 } };
3615 const bdaddr_t ia = { { 0xa6, 0xa5, 0xa4, 0xa3, 0xa2, 0xa1 } };
3616 const u8 exp[16] = {
3617 0x86, 0x3b, 0xf1, 0xbe, 0xc5, 0x4d, 0xa7, 0xd2,
3618 0xea, 0x88, 0x89, 0x87, 0xef, 0x3f, 0x1e, 0x1e };
3619 u8 res[16];
3620 int err;
3621
3622 err = smp_c1(tfm_aes, k, r, preq, pres, _iat, &ia, _rat, &ra, res);
3623 if (err)
3624 return err;
3625
3626 if (crypto_memneq(res, exp, 16))
3627 return -EINVAL;
3628
3629 return 0;
3630 }
3631
3632 static int __init test_s1(struct crypto_cipher *tfm_aes)
3633 {
3634 const u8 k[16] = {
3635 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
3636 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
3637 const u8 r1[16] = {
3638 0x88, 0x77, 0x66, 0x55, 0x44, 0x33, 0x22, 0x11 };
3639 const u8 r2[16] = {
3640 0x00, 0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa, 0x99 };
3641 const u8 exp[16] = {
3642 0x62, 0xa0, 0x6d, 0x79, 0xae, 0x16, 0x42, 0x5b,
3643 0x9b, 0xf4, 0xb0, 0xe8, 0xf0, 0xe1, 0x1f, 0x9a };
3644 u8 res[16];
3645 int err;
3646
3647 err = smp_s1(tfm_aes, k, r1, r2, res);
3648 if (err)
3649 return err;
3650
3651 if (crypto_memneq(res, exp, 16))
3652 return -EINVAL;
3653
3654 return 0;
3655 }
3656
3657 static int __init test_f4(struct crypto_shash *tfm_cmac)
3658 {
3659 const u8 u[32] = {
3660 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
3661 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
3662 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
3663 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 };
3664 const u8 v[32] = {
3665 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b,
3666 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59,
3667 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90,
3668 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 };
3669 const u8 x[16] = {
3670 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3671 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3672 const u8 z = 0x00;
3673 const u8 exp[16] = {
3674 0x2d, 0x87, 0x74, 0xa9, 0xbe, 0xa1, 0xed, 0xf1,
3675 0x1c, 0xbd, 0xa9, 0x07, 0xf1, 0x16, 0xc9, 0xf2 };
3676 u8 res[16];
3677 int err;
3678
3679 err = smp_f4(tfm_cmac, u, v, x, z, res);
3680 if (err)
3681 return err;
3682
3683 if (crypto_memneq(res, exp, 16))
3684 return -EINVAL;
3685
3686 return 0;
3687 }
3688
3689 static int __init test_f5(struct crypto_shash *tfm_cmac)
3690 {
3691 const u8 w[32] = {
3692 0x98, 0xa6, 0xbf, 0x73, 0xf3, 0x34, 0x8d, 0x86,
3693 0xf1, 0x66, 0xf8, 0xb4, 0x13, 0x6b, 0x79, 0x99,
3694 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3695 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3696 const u8 n1[16] = {
3697 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3698 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3699 const u8 n2[16] = {
3700 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3701 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3702 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 };
3703 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 };
3704 const u8 exp_ltk[16] = {
3705 0x38, 0x0a, 0x75, 0x94, 0xb5, 0x22, 0x05, 0x98,
3706 0x23, 0xcd, 0xd7, 0x69, 0x11, 0x79, 0x86, 0x69 };
3707 const u8 exp_mackey[16] = {
3708 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd,
3709 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 };
3710 u8 mackey[16], ltk[16];
3711 int err;
3712
3713 err = smp_f5(tfm_cmac, w, n1, n2, a1, a2, mackey, ltk);
3714 if (err)
3715 return err;
3716
3717 if (crypto_memneq(mackey, exp_mackey, 16))
3718 return -EINVAL;
3719
3720 if (crypto_memneq(ltk, exp_ltk, 16))
3721 return -EINVAL;
3722
3723 return 0;
3724 }
3725
3726 static int __init test_f6(struct crypto_shash *tfm_cmac)
3727 {
3728 const u8 w[16] = {
3729 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd,
3730 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 };
3731 const u8 n1[16] = {
3732 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3733 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3734 const u8 n2[16] = {
3735 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3736 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3737 const u8 r[16] = {
3738 0xc8, 0x0f, 0x2d, 0x0c, 0xd2, 0x42, 0xda, 0x08,
3739 0x54, 0xbb, 0x53, 0xb4, 0x3b, 0x34, 0xa3, 0x12 };
3740 const u8 io_cap[3] = { 0x02, 0x01, 0x01 };
3741 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 };
3742 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 };
3743 const u8 exp[16] = {
3744 0x61, 0x8f, 0x95, 0xda, 0x09, 0x0b, 0x6c, 0xd2,
3745 0xc5, 0xe8, 0xd0, 0x9c, 0x98, 0x73, 0xc4, 0xe3 };
3746 u8 res[16];
3747 int err;
3748
3749 err = smp_f6(tfm_cmac, w, n1, n2, r, io_cap, a1, a2, res);
3750 if (err)
3751 return err;
3752
3753 if (crypto_memneq(res, exp, 16))
3754 return -EINVAL;
3755
3756 return 0;
3757 }
3758
3759 static int __init test_g2(struct crypto_shash *tfm_cmac)
3760 {
3761 const u8 u[32] = {
3762 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
3763 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
3764 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
3765 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 };
3766 const u8 v[32] = {
3767 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b,
3768 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59,
3769 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90,
3770 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 };
3771 const u8 x[16] = {
3772 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3773 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3774 const u8 y[16] = {
3775 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3776 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3777 const u32 exp_val = 0x2f9ed5ba % 1000000;
3778 u32 val;
3779 int err;
3780
3781 err = smp_g2(tfm_cmac, u, v, x, y, &val);
3782 if (err)
3783 return err;
3784
3785 if (val != exp_val)
3786 return -EINVAL;
3787
3788 return 0;
3789 }
3790
3791 static int __init test_h6(struct crypto_shash *tfm_cmac)
3792 {
3793 const u8 w[16] = {
3794 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3795 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3796 const u8 key_id[4] = { 0x72, 0x62, 0x65, 0x6c };
3797 const u8 exp[16] = {
3798 0x99, 0x63, 0xb1, 0x80, 0xe2, 0xa9, 0xd3, 0xe8,
3799 0x1c, 0xc9, 0x6d, 0xe7, 0x02, 0xe1, 0x9a, 0x2d };
3800 u8 res[16];
3801 int err;
3802
3803 err = smp_h6(tfm_cmac, w, key_id, res);
3804 if (err)
3805 return err;
3806
3807 if (crypto_memneq(res, exp, 16))
3808 return -EINVAL;
3809
3810 return 0;
3811 }
3812
3813 static char test_smp_buffer[32];
3814
3815 static ssize_t test_smp_read(struct file *file, char __user *user_buf,
3816 size_t count, loff_t *ppos)
3817 {
3818 return simple_read_from_buffer(user_buf, count, ppos, test_smp_buffer,
3819 strlen(test_smp_buffer));
3820 }
3821
3822 static const struct file_operations test_smp_fops = {
3823 .open = simple_open,
3824 .read = test_smp_read,
3825 .llseek = default_llseek,
3826 };
3827
3828 static int __init run_selftests(struct crypto_cipher *tfm_aes,
3829 struct crypto_shash *tfm_cmac,
3830 struct crypto_kpp *tfm_ecdh)
3831 {
3832 ktime_t calltime, delta, rettime;
3833 unsigned long long duration;
3834 int err;
3835
3836 calltime = ktime_get();
3837
3838 err = test_debug_key(tfm_ecdh);
3839 if (err) {
3840 BT_ERR("debug_key test failed");
3841 goto done;
3842 }
3843
3844 err = test_ah(tfm_aes);
3845 if (err) {
3846 BT_ERR("smp_ah test failed");
3847 goto done;
3848 }
3849
3850 err = test_c1(tfm_aes);
3851 if (err) {
3852 BT_ERR("smp_c1 test failed");
3853 goto done;
3854 }
3855
3856 err = test_s1(tfm_aes);
3857 if (err) {
3858 BT_ERR("smp_s1 test failed");
3859 goto done;
3860 }
3861
3862 err = test_f4(tfm_cmac);
3863 if (err) {
3864 BT_ERR("smp_f4 test failed");
3865 goto done;
3866 }
3867
3868 err = test_f5(tfm_cmac);
3869 if (err) {
3870 BT_ERR("smp_f5 test failed");
3871 goto done;
3872 }
3873
3874 err = test_f6(tfm_cmac);
3875 if (err) {
3876 BT_ERR("smp_f6 test failed");
3877 goto done;
3878 }
3879
3880 err = test_g2(tfm_cmac);
3881 if (err) {
3882 BT_ERR("smp_g2 test failed");
3883 goto done;
3884 }
3885
3886 err = test_h6(tfm_cmac);
3887 if (err) {
3888 BT_ERR("smp_h6 test failed");
3889 goto done;
3890 }
3891
3892 rettime = ktime_get();
3893 delta = ktime_sub(rettime, calltime);
3894 duration = (unsigned long long) ktime_to_ns(delta) >> 10;
3895
3896 BT_INFO("SMP test passed in %llu usecs", duration);
3897
3898 done:
3899 if (!err)
3900 snprintf(test_smp_buffer, sizeof(test_smp_buffer),
3901 "PASS (%llu usecs)\n", duration);
3902 else
3903 snprintf(test_smp_buffer, sizeof(test_smp_buffer), "FAIL\n");
3904
3905 debugfs_create_file("selftest_smp", 0444, bt_debugfs, NULL,
3906 &test_smp_fops);
3907
3908 return err;
3909 }
3910
3911 int __init bt_selftest_smp(void)
3912 {
3913 struct crypto_cipher *tfm_aes;
3914 struct crypto_shash *tfm_cmac;
3915 struct crypto_kpp *tfm_ecdh;
3916 int err;
3917
3918 tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
3919 if (IS_ERR(tfm_aes)) {
3920 BT_ERR("Unable to create AES crypto context");
3921 return PTR_ERR(tfm_aes);
3922 }
3923
3924 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, CRYPTO_ALG_ASYNC);
3925 if (IS_ERR(tfm_cmac)) {
3926 BT_ERR("Unable to create CMAC crypto context");
3927 crypto_free_cipher(tfm_aes);
3928 return PTR_ERR(tfm_cmac);
3929 }
3930
3931 tfm_ecdh = crypto_alloc_kpp("ecdh", CRYPTO_ALG_INTERNAL, 0);
3932 if (IS_ERR(tfm_ecdh)) {
3933 BT_ERR("Unable to create ECDH crypto context");
3934 crypto_free_shash(tfm_cmac);
3935 crypto_free_cipher(tfm_aes);
3936 return PTR_ERR(tfm_ecdh);
3937 }
3938
3939 err = run_selftests(tfm_aes, tfm_cmac, tfm_ecdh);
3940
3941 crypto_free_shash(tfm_cmac);
3942 crypto_free_cipher(tfm_aes);
3943 crypto_free_kpp(tfm_ecdh);
3944
3945 return err;
3946 }
3947
3948 #endif
ubuntu-bionic-kernel mirror