xref: /openbmc/linux/net/bluetooth/smp.c (revision bc5aa3a0)
1 /*
2    BlueZ - Bluetooth protocol stack for Linux
3    Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
4 
5    This program is free software; you can redistribute it and/or modify
6    it under the terms of the GNU General Public License version 2 as
7    published by the Free Software Foundation;
8 
9    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
10    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
11    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
12    IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
13    CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
14    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 
18    ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
19    COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
20    SOFTWARE IS DISCLAIMED.
21 */
22 
23 #include <linux/debugfs.h>
24 #include <linux/scatterlist.h>
25 #include <linux/crypto.h>
26 #include <crypto/b128ops.h>
27 #include <crypto/hash.h>
28 
29 #include <net/bluetooth/bluetooth.h>
30 #include <net/bluetooth/hci_core.h>
31 #include <net/bluetooth/l2cap.h>
32 #include <net/bluetooth/mgmt.h>
33 
34 #include "ecc.h"
35 #include "smp.h"
36 
37 #define SMP_DEV(hdev) \
38 	((struct smp_dev *)((struct l2cap_chan *)((hdev)->smp_data))->data)
39 
40 /* Low-level debug macros to be used for stuff that we don't want
41  * accidentially in dmesg, i.e. the values of the various crypto keys
42  * and the inputs & outputs of crypto functions.
43  */
44 #ifdef DEBUG
45 #define SMP_DBG(fmt, ...) printk(KERN_DEBUG "%s: " fmt, __func__, \
46 				 ##__VA_ARGS__)
47 #else
48 #define SMP_DBG(fmt, ...) no_printk(KERN_DEBUG "%s: " fmt, __func__, \
49 				    ##__VA_ARGS__)
50 #endif
51 
52 #define SMP_ALLOW_CMD(smp, code)	set_bit(code, &smp->allow_cmd)
53 
54 /* Keys which are not distributed with Secure Connections */
55 #define SMP_SC_NO_DIST (SMP_DIST_ENC_KEY | SMP_DIST_LINK_KEY);
56 
57 #define SMP_TIMEOUT	msecs_to_jiffies(30000)
58 
59 #define AUTH_REQ_MASK(dev)	(hci_dev_test_flag(dev, HCI_SC_ENABLED) ? \
60 				 0x1f : 0x07)
61 #define KEY_DIST_MASK		0x07
62 
63 /* Maximum message length that can be passed to aes_cmac */
64 #define CMAC_MSG_MAX	80
65 
66 enum {
67 	SMP_FLAG_TK_VALID,
68 	SMP_FLAG_CFM_PENDING,
69 	SMP_FLAG_MITM_AUTH,
70 	SMP_FLAG_COMPLETE,
71 	SMP_FLAG_INITIATOR,
72 	SMP_FLAG_SC,
73 	SMP_FLAG_REMOTE_PK,
74 	SMP_FLAG_DEBUG_KEY,
75 	SMP_FLAG_WAIT_USER,
76 	SMP_FLAG_DHKEY_PENDING,
77 	SMP_FLAG_REMOTE_OOB,
78 	SMP_FLAG_LOCAL_OOB,
79 };
80 
81 struct smp_dev {
82 	/* Secure Connections OOB data */
83 	u8			local_pk[64];
84 	u8			local_sk[32];
85 	u8			local_rand[16];
86 	bool			debug_key;
87 
88 	u8			min_key_size;
89 	u8			max_key_size;
90 
91 	struct crypto_cipher	*tfm_aes;
92 	struct crypto_shash	*tfm_cmac;
93 };
94 
95 struct smp_chan {
96 	struct l2cap_conn	*conn;
97 	struct delayed_work	security_timer;
98 	unsigned long           allow_cmd; /* Bitmask of allowed commands */
99 
100 	u8		preq[7]; /* SMP Pairing Request */
101 	u8		prsp[7]; /* SMP Pairing Response */
102 	u8		prnd[16]; /* SMP Pairing Random (local) */
103 	u8		rrnd[16]; /* SMP Pairing Random (remote) */
104 	u8		pcnf[16]; /* SMP Pairing Confirm */
105 	u8		tk[16]; /* SMP Temporary Key */
106 	u8		rr[16]; /* Remote OOB ra/rb value */
107 	u8		lr[16]; /* Local OOB ra/rb value */
108 	u8		enc_key_size;
109 	u8		remote_key_dist;
110 	bdaddr_t	id_addr;
111 	u8		id_addr_type;
112 	u8		irk[16];
113 	struct smp_csrk	*csrk;
114 	struct smp_csrk	*slave_csrk;
115 	struct smp_ltk	*ltk;
116 	struct smp_ltk	*slave_ltk;
117 	struct smp_irk	*remote_irk;
118 	u8		*link_key;
119 	unsigned long	flags;
120 	u8		method;
121 	u8		passkey_round;
122 
123 	/* Secure Connections variables */
124 	u8			local_pk[64];
125 	u8			local_sk[32];
126 	u8			remote_pk[64];
127 	u8			dhkey[32];
128 	u8			mackey[16];
129 
130 	struct crypto_cipher	*tfm_aes;
131 	struct crypto_shash	*tfm_cmac;
132 };
133 
134 /* These debug key values are defined in the SMP section of the core
135  * specification. debug_pk is the public debug key and debug_sk the
136  * private debug key.
137  */
138 static const u8 debug_pk[64] = {
139 		0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
140 		0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
141 		0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
142 		0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20,
143 
144 		0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74,
145 		0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76,
146 		0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63,
147 		0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc,
148 };
149 
150 static const u8 debug_sk[32] = {
151 		0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58,
152 		0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a,
153 		0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74,
154 		0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f,
155 };
156 
157 static inline void swap_buf(const u8 *src, u8 *dst, size_t len)
158 {
159 	size_t i;
160 
161 	for (i = 0; i < len; i++)
162 		dst[len - 1 - i] = src[i];
163 }
164 
165 /* The following functions map to the LE SC SMP crypto functions
166  * AES-CMAC, f4, f5, f6, g2 and h6.
167  */
168 
169 static int aes_cmac(struct crypto_shash *tfm, const u8 k[16], const u8 *m,
170 		    size_t len, u8 mac[16])
171 {
172 	uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX];
173 	SHASH_DESC_ON_STACK(desc, tfm);
174 	int err;
175 
176 	if (len > CMAC_MSG_MAX)
177 		return -EFBIG;
178 
179 	if (!tfm) {
180 		BT_ERR("tfm %p", tfm);
181 		return -EINVAL;
182 	}
183 
184 	desc->tfm = tfm;
185 	desc->flags = 0;
186 
187 	/* Swap key and message from LSB to MSB */
188 	swap_buf(k, tmp, 16);
189 	swap_buf(m, msg_msb, len);
190 
191 	SMP_DBG("msg (len %zu) %*phN", len, (int) len, m);
192 	SMP_DBG("key %16phN", k);
193 
194 	err = crypto_shash_setkey(tfm, tmp, 16);
195 	if (err) {
196 		BT_ERR("cipher setkey failed: %d", err);
197 		return err;
198 	}
199 
200 	err = crypto_shash_digest(desc, msg_msb, len, mac_msb);
201 	shash_desc_zero(desc);
202 	if (err) {
203 		BT_ERR("Hash computation error %d", err);
204 		return err;
205 	}
206 
207 	swap_buf(mac_msb, mac, 16);
208 
209 	SMP_DBG("mac %16phN", mac);
210 
211 	return 0;
212 }
213 
214 static int smp_f4(struct crypto_shash *tfm_cmac, const u8 u[32],
215 		  const u8 v[32], const u8 x[16], u8 z, u8 res[16])
216 {
217 	u8 m[65];
218 	int err;
219 
220 	SMP_DBG("u %32phN", u);
221 	SMP_DBG("v %32phN", v);
222 	SMP_DBG("x %16phN z %02x", x, z);
223 
224 	m[0] = z;
225 	memcpy(m + 1, v, 32);
226 	memcpy(m + 33, u, 32);
227 
228 	err = aes_cmac(tfm_cmac, x, m, sizeof(m), res);
229 	if (err)
230 		return err;
231 
232 	SMP_DBG("res %16phN", res);
233 
234 	return err;
235 }
236 
237 static int smp_f5(struct crypto_shash *tfm_cmac, const u8 w[32],
238 		  const u8 n1[16], const u8 n2[16], const u8 a1[7],
239 		  const u8 a2[7], u8 mackey[16], u8 ltk[16])
240 {
241 	/* The btle, salt and length "magic" values are as defined in
242 	 * the SMP section of the Bluetooth core specification. In ASCII
243 	 * the btle value ends up being 'btle'. The salt is just a
244 	 * random number whereas length is the value 256 in little
245 	 * endian format.
246 	 */
247 	const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 };
248 	const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60,
249 			      0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c };
250 	const u8 length[2] = { 0x00, 0x01 };
251 	u8 m[53], t[16];
252 	int err;
253 
254 	SMP_DBG("w %32phN", w);
255 	SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
256 	SMP_DBG("a1 %7phN a2 %7phN", a1, a2);
257 
258 	err = aes_cmac(tfm_cmac, salt, w, 32, t);
259 	if (err)
260 		return err;
261 
262 	SMP_DBG("t %16phN", t);
263 
264 	memcpy(m, length, 2);
265 	memcpy(m + 2, a2, 7);
266 	memcpy(m + 9, a1, 7);
267 	memcpy(m + 16, n2, 16);
268 	memcpy(m + 32, n1, 16);
269 	memcpy(m + 48, btle, 4);
270 
271 	m[52] = 0; /* Counter */
272 
273 	err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey);
274 	if (err)
275 		return err;
276 
277 	SMP_DBG("mackey %16phN", mackey);
278 
279 	m[52] = 1; /* Counter */
280 
281 	err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk);
282 	if (err)
283 		return err;
284 
285 	SMP_DBG("ltk %16phN", ltk);
286 
287 	return 0;
288 }
289 
290 static int smp_f6(struct crypto_shash *tfm_cmac, const u8 w[16],
291 		  const u8 n1[16], const u8 n2[16], const u8 r[16],
292 		  const u8 io_cap[3], const u8 a1[7], const u8 a2[7],
293 		  u8 res[16])
294 {
295 	u8 m[65];
296 	int err;
297 
298 	SMP_DBG("w %16phN", w);
299 	SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
300 	SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2);
301 
302 	memcpy(m, a2, 7);
303 	memcpy(m + 7, a1, 7);
304 	memcpy(m + 14, io_cap, 3);
305 	memcpy(m + 17, r, 16);
306 	memcpy(m + 33, n2, 16);
307 	memcpy(m + 49, n1, 16);
308 
309 	err = aes_cmac(tfm_cmac, w, m, sizeof(m), res);
310 	if (err)
311 		return err;
312 
313 	SMP_DBG("res %16phN", res);
314 
315 	return err;
316 }
317 
318 static int smp_g2(struct crypto_shash *tfm_cmac, const u8 u[32], const u8 v[32],
319 		  const u8 x[16], const u8 y[16], u32 *val)
320 {
321 	u8 m[80], tmp[16];
322 	int err;
323 
324 	SMP_DBG("u %32phN", u);
325 	SMP_DBG("v %32phN", v);
326 	SMP_DBG("x %16phN y %16phN", x, y);
327 
328 	memcpy(m, y, 16);
329 	memcpy(m + 16, v, 32);
330 	memcpy(m + 48, u, 32);
331 
332 	err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp);
333 	if (err)
334 		return err;
335 
336 	*val = get_unaligned_le32(tmp);
337 	*val %= 1000000;
338 
339 	SMP_DBG("val %06u", *val);
340 
341 	return 0;
342 }
343 
344 static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16],
345 		  const u8 key_id[4], u8 res[16])
346 {
347 	int err;
348 
349 	SMP_DBG("w %16phN key_id %4phN", w, key_id);
350 
351 	err = aes_cmac(tfm_cmac, w, key_id, 4, res);
352 	if (err)
353 		return err;
354 
355 	SMP_DBG("res %16phN", res);
356 
357 	return err;
358 }
359 
360 /* The following functions map to the legacy SMP crypto functions e, c1,
361  * s1 and ah.
362  */
363 
364 static int smp_e(struct crypto_cipher *tfm, const u8 *k, u8 *r)
365 {
366 	uint8_t tmp[16], data[16];
367 	int err;
368 
369 	SMP_DBG("k %16phN r %16phN", k, r);
370 
371 	if (!tfm) {
372 		BT_ERR("tfm %p", tfm);
373 		return -EINVAL;
374 	}
375 
376 	/* The most significant octet of key corresponds to k[0] */
377 	swap_buf(k, tmp, 16);
378 
379 	err = crypto_cipher_setkey(tfm, tmp, 16);
380 	if (err) {
381 		BT_ERR("cipher setkey failed: %d", err);
382 		return err;
383 	}
384 
385 	/* Most significant octet of plaintextData corresponds to data[0] */
386 	swap_buf(r, data, 16);
387 
388 	crypto_cipher_encrypt_one(tfm, data, data);
389 
390 	/* Most significant octet of encryptedData corresponds to data[0] */
391 	swap_buf(data, r, 16);
392 
393 	SMP_DBG("r %16phN", r);
394 
395 	return err;
396 }
397 
398 static int smp_c1(struct crypto_cipher *tfm_aes, const u8 k[16],
399 		  const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat,
400 		  const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16])
401 {
402 	u8 p1[16], p2[16];
403 	int err;
404 
405 	SMP_DBG("k %16phN r %16phN", k, r);
406 	SMP_DBG("iat %u ia %6phN rat %u ra %6phN", _iat, ia, _rat, ra);
407 	SMP_DBG("preq %7phN pres %7phN", preq, pres);
408 
409 	memset(p1, 0, 16);
410 
411 	/* p1 = pres || preq || _rat || _iat */
412 	p1[0] = _iat;
413 	p1[1] = _rat;
414 	memcpy(p1 + 2, preq, 7);
415 	memcpy(p1 + 9, pres, 7);
416 
417 	SMP_DBG("p1 %16phN", p1);
418 
419 	/* res = r XOR p1 */
420 	u128_xor((u128 *) res, (u128 *) r, (u128 *) p1);
421 
422 	/* res = e(k, res) */
423 	err = smp_e(tfm_aes, k, res);
424 	if (err) {
425 		BT_ERR("Encrypt data error");
426 		return err;
427 	}
428 
429 	/* p2 = padding || ia || ra */
430 	memcpy(p2, ra, 6);
431 	memcpy(p2 + 6, ia, 6);
432 	memset(p2 + 12, 0, 4);
433 
434 	SMP_DBG("p2 %16phN", p2);
435 
436 	/* res = res XOR p2 */
437 	u128_xor((u128 *) res, (u128 *) res, (u128 *) p2);
438 
439 	/* res = e(k, res) */
440 	err = smp_e(tfm_aes, k, res);
441 	if (err)
442 		BT_ERR("Encrypt data error");
443 
444 	return err;
445 }
446 
447 static int smp_s1(struct crypto_cipher *tfm_aes, const u8 k[16],
448 		  const u8 r1[16], const u8 r2[16], u8 _r[16])
449 {
450 	int err;
451 
452 	/* Just least significant octets from r1 and r2 are considered */
453 	memcpy(_r, r2, 8);
454 	memcpy(_r + 8, r1, 8);
455 
456 	err = smp_e(tfm_aes, k, _r);
457 	if (err)
458 		BT_ERR("Encrypt data error");
459 
460 	return err;
461 }
462 
463 static int smp_ah(struct crypto_cipher *tfm, const u8 irk[16],
464 		  const u8 r[3], u8 res[3])
465 {
466 	u8 _res[16];
467 	int err;
468 
469 	/* r' = padding || r */
470 	memcpy(_res, r, 3);
471 	memset(_res + 3, 0, 13);
472 
473 	err = smp_e(tfm, irk, _res);
474 	if (err) {
475 		BT_ERR("Encrypt error");
476 		return err;
477 	}
478 
479 	/* The output of the random address function ah is:
480 	 *	ah(k, r) = e(k, r') mod 2^24
481 	 * The output of the security function e is then truncated to 24 bits
482 	 * by taking the least significant 24 bits of the output of e as the
483 	 * result of ah.
484 	 */
485 	memcpy(res, _res, 3);
486 
487 	return 0;
488 }
489 
490 bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16],
491 		     const bdaddr_t *bdaddr)
492 {
493 	struct l2cap_chan *chan = hdev->smp_data;
494 	struct smp_dev *smp;
495 	u8 hash[3];
496 	int err;
497 
498 	if (!chan || !chan->data)
499 		return false;
500 
501 	smp = chan->data;
502 
503 	BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk);
504 
505 	err = smp_ah(smp->tfm_aes, irk, &bdaddr->b[3], hash);
506 	if (err)
507 		return false;
508 
509 	return !memcmp(bdaddr->b, hash, 3);
510 }
511 
512 int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa)
513 {
514 	struct l2cap_chan *chan = hdev->smp_data;
515 	struct smp_dev *smp;
516 	int err;
517 
518 	if (!chan || !chan->data)
519 		return -EOPNOTSUPP;
520 
521 	smp = chan->data;
522 
523 	get_random_bytes(&rpa->b[3], 3);
524 
525 	rpa->b[5] &= 0x3f;	/* Clear two most significant bits */
526 	rpa->b[5] |= 0x40;	/* Set second most significant bit */
527 
528 	err = smp_ah(smp->tfm_aes, irk, &rpa->b[3], rpa->b);
529 	if (err < 0)
530 		return err;
531 
532 	BT_DBG("RPA %pMR", rpa);
533 
534 	return 0;
535 }
536 
537 int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16])
538 {
539 	struct l2cap_chan *chan = hdev->smp_data;
540 	struct smp_dev *smp;
541 	int err;
542 
543 	if (!chan || !chan->data)
544 		return -EOPNOTSUPP;
545 
546 	smp = chan->data;
547 
548 	if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
549 		BT_DBG("Using debug keys");
550 		memcpy(smp->local_pk, debug_pk, 64);
551 		memcpy(smp->local_sk, debug_sk, 32);
552 		smp->debug_key = true;
553 	} else {
554 		while (true) {
555 			/* Generate local key pair for Secure Connections */
556 			if (!ecc_make_key(smp->local_pk, smp->local_sk))
557 				return -EIO;
558 
559 			/* This is unlikely, but we need to check that
560 			 * we didn't accidentially generate a debug key.
561 			 */
562 			if (memcmp(smp->local_sk, debug_sk, 32))
563 				break;
564 		}
565 		smp->debug_key = false;
566 	}
567 
568 	SMP_DBG("OOB Public Key X: %32phN", smp->local_pk);
569 	SMP_DBG("OOB Public Key Y: %32phN", smp->local_pk + 32);
570 	SMP_DBG("OOB Private Key:  %32phN", smp->local_sk);
571 
572 	get_random_bytes(smp->local_rand, 16);
573 
574 	err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->local_pk,
575 		     smp->local_rand, 0, hash);
576 	if (err < 0)
577 		return err;
578 
579 	memcpy(rand, smp->local_rand, 16);
580 
581 	return 0;
582 }
583 
584 static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
585 {
586 	struct l2cap_chan *chan = conn->smp;
587 	struct smp_chan *smp;
588 	struct kvec iv[2];
589 	struct msghdr msg;
590 
591 	if (!chan)
592 		return;
593 
594 	BT_DBG("code 0x%2.2x", code);
595 
596 	iv[0].iov_base = &code;
597 	iv[0].iov_len = 1;
598 
599 	iv[1].iov_base = data;
600 	iv[1].iov_len = len;
601 
602 	memset(&msg, 0, sizeof(msg));
603 
604 	iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iv, 2, 1 + len);
605 
606 	l2cap_chan_send(chan, &msg, 1 + len);
607 
608 	if (!chan->data)
609 		return;
610 
611 	smp = chan->data;
612 
613 	cancel_delayed_work_sync(&smp->security_timer);
614 	schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT);
615 }
616 
617 static u8 authreq_to_seclevel(u8 authreq)
618 {
619 	if (authreq & SMP_AUTH_MITM) {
620 		if (authreq & SMP_AUTH_SC)
621 			return BT_SECURITY_FIPS;
622 		else
623 			return BT_SECURITY_HIGH;
624 	} else {
625 		return BT_SECURITY_MEDIUM;
626 	}
627 }
628 
629 static __u8 seclevel_to_authreq(__u8 sec_level)
630 {
631 	switch (sec_level) {
632 	case BT_SECURITY_FIPS:
633 	case BT_SECURITY_HIGH:
634 		return SMP_AUTH_MITM | SMP_AUTH_BONDING;
635 	case BT_SECURITY_MEDIUM:
636 		return SMP_AUTH_BONDING;
637 	default:
638 		return SMP_AUTH_NONE;
639 	}
640 }
641 
642 static void build_pairing_cmd(struct l2cap_conn *conn,
643 			      struct smp_cmd_pairing *req,
644 			      struct smp_cmd_pairing *rsp, __u8 authreq)
645 {
646 	struct l2cap_chan *chan = conn->smp;
647 	struct smp_chan *smp = chan->data;
648 	struct hci_conn *hcon = conn->hcon;
649 	struct hci_dev *hdev = hcon->hdev;
650 	u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT;
651 
652 	if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
653 		local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
654 		remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
655 		authreq |= SMP_AUTH_BONDING;
656 	} else {
657 		authreq &= ~SMP_AUTH_BONDING;
658 	}
659 
660 	if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
661 		remote_dist |= SMP_DIST_ID_KEY;
662 
663 	if (hci_dev_test_flag(hdev, HCI_PRIVACY))
664 		local_dist |= SMP_DIST_ID_KEY;
665 
666 	if (hci_dev_test_flag(hdev, HCI_SC_ENABLED) &&
667 	    (authreq & SMP_AUTH_SC)) {
668 		struct oob_data *oob_data;
669 		u8 bdaddr_type;
670 
671 		if (hci_dev_test_flag(hdev, HCI_SSP_ENABLED)) {
672 			local_dist |= SMP_DIST_LINK_KEY;
673 			remote_dist |= SMP_DIST_LINK_KEY;
674 		}
675 
676 		if (hcon->dst_type == ADDR_LE_DEV_PUBLIC)
677 			bdaddr_type = BDADDR_LE_PUBLIC;
678 		else
679 			bdaddr_type = BDADDR_LE_RANDOM;
680 
681 		oob_data = hci_find_remote_oob_data(hdev, &hcon->dst,
682 						    bdaddr_type);
683 		if (oob_data && oob_data->present) {
684 			set_bit(SMP_FLAG_REMOTE_OOB, &smp->flags);
685 			oob_flag = SMP_OOB_PRESENT;
686 			memcpy(smp->rr, oob_data->rand256, 16);
687 			memcpy(smp->pcnf, oob_data->hash256, 16);
688 			SMP_DBG("OOB Remote Confirmation: %16phN", smp->pcnf);
689 			SMP_DBG("OOB Remote Random: %16phN", smp->rr);
690 		}
691 
692 	} else {
693 		authreq &= ~SMP_AUTH_SC;
694 	}
695 
696 	if (rsp == NULL) {
697 		req->io_capability = conn->hcon->io_capability;
698 		req->oob_flag = oob_flag;
699 		req->max_key_size = SMP_DEV(hdev)->max_key_size;
700 		req->init_key_dist = local_dist;
701 		req->resp_key_dist = remote_dist;
702 		req->auth_req = (authreq & AUTH_REQ_MASK(hdev));
703 
704 		smp->remote_key_dist = remote_dist;
705 		return;
706 	}
707 
708 	rsp->io_capability = conn->hcon->io_capability;
709 	rsp->oob_flag = oob_flag;
710 	rsp->max_key_size = SMP_DEV(hdev)->max_key_size;
711 	rsp->init_key_dist = req->init_key_dist & remote_dist;
712 	rsp->resp_key_dist = req->resp_key_dist & local_dist;
713 	rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev));
714 
715 	smp->remote_key_dist = rsp->init_key_dist;
716 }
717 
718 static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)
719 {
720 	struct l2cap_chan *chan = conn->smp;
721 	struct hci_dev *hdev = conn->hcon->hdev;
722 	struct smp_chan *smp = chan->data;
723 
724 	if (max_key_size > SMP_DEV(hdev)->max_key_size ||
725 	    max_key_size < SMP_MIN_ENC_KEY_SIZE)
726 		return SMP_ENC_KEY_SIZE;
727 
728 	smp->enc_key_size = max_key_size;
729 
730 	return 0;
731 }
732 
733 static void smp_chan_destroy(struct l2cap_conn *conn)
734 {
735 	struct l2cap_chan *chan = conn->smp;
736 	struct smp_chan *smp = chan->data;
737 	struct hci_conn *hcon = conn->hcon;
738 	bool complete;
739 
740 	BUG_ON(!smp);
741 
742 	cancel_delayed_work_sync(&smp->security_timer);
743 
744 	complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags);
745 	mgmt_smp_complete(hcon, complete);
746 
747 	kzfree(smp->csrk);
748 	kzfree(smp->slave_csrk);
749 	kzfree(smp->link_key);
750 
751 	crypto_free_cipher(smp->tfm_aes);
752 	crypto_free_shash(smp->tfm_cmac);
753 
754 	/* Ensure that we don't leave any debug key around if debug key
755 	 * support hasn't been explicitly enabled.
756 	 */
757 	if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG &&
758 	    !hci_dev_test_flag(hcon->hdev, HCI_KEEP_DEBUG_KEYS)) {
759 		list_del_rcu(&smp->ltk->list);
760 		kfree_rcu(smp->ltk, rcu);
761 		smp->ltk = NULL;
762 	}
763 
764 	/* If pairing failed clean up any keys we might have */
765 	if (!complete) {
766 		if (smp->ltk) {
767 			list_del_rcu(&smp->ltk->list);
768 			kfree_rcu(smp->ltk, rcu);
769 		}
770 
771 		if (smp->slave_ltk) {
772 			list_del_rcu(&smp->slave_ltk->list);
773 			kfree_rcu(smp->slave_ltk, rcu);
774 		}
775 
776 		if (smp->remote_irk) {
777 			list_del_rcu(&smp->remote_irk->list);
778 			kfree_rcu(smp->remote_irk, rcu);
779 		}
780 	}
781 
782 	chan->data = NULL;
783 	kzfree(smp);
784 	hci_conn_drop(hcon);
785 }
786 
787 static void smp_failure(struct l2cap_conn *conn, u8 reason)
788 {
789 	struct hci_conn *hcon = conn->hcon;
790 	struct l2cap_chan *chan = conn->smp;
791 
792 	if (reason)
793 		smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
794 			     &reason);
795 
796 	mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE);
797 
798 	if (chan->data)
799 		smp_chan_destroy(conn);
800 }
801 
802 #define JUST_WORKS	0x00
803 #define JUST_CFM	0x01
804 #define REQ_PASSKEY	0x02
805 #define CFM_PASSKEY	0x03
806 #define REQ_OOB		0x04
807 #define DSP_PASSKEY	0x05
808 #define OVERLAP		0xFF
809 
810 static const u8 gen_method[5][5] = {
811 	{ JUST_WORKS,  JUST_CFM,    REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
812 	{ JUST_WORKS,  JUST_CFM,    REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
813 	{ CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
814 	{ JUST_WORKS,  JUST_CFM,    JUST_WORKS,  JUST_WORKS, JUST_CFM    },
815 	{ CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP     },
816 };
817 
818 static const u8 sc_method[5][5] = {
819 	{ JUST_WORKS,  JUST_CFM,    REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
820 	{ JUST_WORKS,  CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
821 	{ DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY },
822 	{ JUST_WORKS,  JUST_CFM,    JUST_WORKS,  JUST_WORKS, JUST_CFM    },
823 	{ DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
824 };
825 
826 static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io)
827 {
828 	/* If either side has unknown io_caps, use JUST_CFM (which gets
829 	 * converted later to JUST_WORKS if we're initiators.
830 	 */
831 	if (local_io > SMP_IO_KEYBOARD_DISPLAY ||
832 	    remote_io > SMP_IO_KEYBOARD_DISPLAY)
833 		return JUST_CFM;
834 
835 	if (test_bit(SMP_FLAG_SC, &smp->flags))
836 		return sc_method[remote_io][local_io];
837 
838 	return gen_method[remote_io][local_io];
839 }
840 
841 static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
842 						u8 local_io, u8 remote_io)
843 {
844 	struct hci_conn *hcon = conn->hcon;
845 	struct l2cap_chan *chan = conn->smp;
846 	struct smp_chan *smp = chan->data;
847 	u32 passkey = 0;
848 	int ret = 0;
849 
850 	/* Initialize key for JUST WORKS */
851 	memset(smp->tk, 0, sizeof(smp->tk));
852 	clear_bit(SMP_FLAG_TK_VALID, &smp->flags);
853 
854 	BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io);
855 
856 	/* If neither side wants MITM, either "just" confirm an incoming
857 	 * request or use just-works for outgoing ones. The JUST_CFM
858 	 * will be converted to JUST_WORKS if necessary later in this
859 	 * function. If either side has MITM look up the method from the
860 	 * table.
861 	 */
862 	if (!(auth & SMP_AUTH_MITM))
863 		smp->method = JUST_CFM;
864 	else
865 		smp->method = get_auth_method(smp, local_io, remote_io);
866 
867 	/* Don't confirm locally initiated pairing attempts */
868 	if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR,
869 						&smp->flags))
870 		smp->method = JUST_WORKS;
871 
872 	/* Don't bother user space with no IO capabilities */
873 	if (smp->method == JUST_CFM &&
874 	    hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
875 		smp->method = JUST_WORKS;
876 
877 	/* If Just Works, Continue with Zero TK */
878 	if (smp->method == JUST_WORKS) {
879 		set_bit(SMP_FLAG_TK_VALID, &smp->flags);
880 		return 0;
881 	}
882 
883 	/* If this function is used for SC -> legacy fallback we
884 	 * can only recover the just-works case.
885 	 */
886 	if (test_bit(SMP_FLAG_SC, &smp->flags))
887 		return -EINVAL;
888 
889 	/* Not Just Works/Confirm results in MITM Authentication */
890 	if (smp->method != JUST_CFM) {
891 		set_bit(SMP_FLAG_MITM_AUTH, &smp->flags);
892 		if (hcon->pending_sec_level < BT_SECURITY_HIGH)
893 			hcon->pending_sec_level = BT_SECURITY_HIGH;
894 	}
895 
896 	/* If both devices have Keyoard-Display I/O, the master
897 	 * Confirms and the slave Enters the passkey.
898 	 */
899 	if (smp->method == OVERLAP) {
900 		if (hcon->role == HCI_ROLE_MASTER)
901 			smp->method = CFM_PASSKEY;
902 		else
903 			smp->method = REQ_PASSKEY;
904 	}
905 
906 	/* Generate random passkey. */
907 	if (smp->method == CFM_PASSKEY) {
908 		memset(smp->tk, 0, sizeof(smp->tk));
909 		get_random_bytes(&passkey, sizeof(passkey));
910 		passkey %= 1000000;
911 		put_unaligned_le32(passkey, smp->tk);
912 		BT_DBG("PassKey: %d", passkey);
913 		set_bit(SMP_FLAG_TK_VALID, &smp->flags);
914 	}
915 
916 	if (smp->method == REQ_PASSKEY)
917 		ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst,
918 						hcon->type, hcon->dst_type);
919 	else if (smp->method == JUST_CFM)
920 		ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
921 						hcon->type, hcon->dst_type,
922 						passkey, 1);
923 	else
924 		ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst,
925 						hcon->type, hcon->dst_type,
926 						passkey, 0);
927 
928 	return ret;
929 }
930 
931 static u8 smp_confirm(struct smp_chan *smp)
932 {
933 	struct l2cap_conn *conn = smp->conn;
934 	struct smp_cmd_pairing_confirm cp;
935 	int ret;
936 
937 	BT_DBG("conn %p", conn);
938 
939 	ret = smp_c1(smp->tfm_aes, smp->tk, smp->prnd, smp->preq, smp->prsp,
940 		     conn->hcon->init_addr_type, &conn->hcon->init_addr,
941 		     conn->hcon->resp_addr_type, &conn->hcon->resp_addr,
942 		     cp.confirm_val);
943 	if (ret)
944 		return SMP_UNSPECIFIED;
945 
946 	clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
947 
948 	smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
949 
950 	if (conn->hcon->out)
951 		SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
952 	else
953 		SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
954 
955 	return 0;
956 }
957 
958 static u8 smp_random(struct smp_chan *smp)
959 {
960 	struct l2cap_conn *conn = smp->conn;
961 	struct hci_conn *hcon = conn->hcon;
962 	u8 confirm[16];
963 	int ret;
964 
965 	if (IS_ERR_OR_NULL(smp->tfm_aes))
966 		return SMP_UNSPECIFIED;
967 
968 	BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
969 
970 	ret = smp_c1(smp->tfm_aes, smp->tk, smp->rrnd, smp->preq, smp->prsp,
971 		     hcon->init_addr_type, &hcon->init_addr,
972 		     hcon->resp_addr_type, &hcon->resp_addr, confirm);
973 	if (ret)
974 		return SMP_UNSPECIFIED;
975 
976 	if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) {
977 		BT_ERR("Pairing failed (confirmation values mismatch)");
978 		return SMP_CONFIRM_FAILED;
979 	}
980 
981 	if (hcon->out) {
982 		u8 stk[16];
983 		__le64 rand = 0;
984 		__le16 ediv = 0;
985 
986 		smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk);
987 
988 		if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
989 			return SMP_UNSPECIFIED;
990 
991 		hci_le_start_enc(hcon, ediv, rand, stk, smp->enc_key_size);
992 		hcon->enc_key_size = smp->enc_key_size;
993 		set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
994 	} else {
995 		u8 stk[16], auth;
996 		__le64 rand = 0;
997 		__le16 ediv = 0;
998 
999 		smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1000 			     smp->prnd);
1001 
1002 		smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk);
1003 
1004 		if (hcon->pending_sec_level == BT_SECURITY_HIGH)
1005 			auth = 1;
1006 		else
1007 			auth = 0;
1008 
1009 		/* Even though there's no _SLAVE suffix this is the
1010 		 * slave STK we're adding for later lookup (the master
1011 		 * STK never needs to be stored).
1012 		 */
1013 		hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1014 			    SMP_STK, auth, stk, smp->enc_key_size, ediv, rand);
1015 	}
1016 
1017 	return 0;
1018 }
1019 
1020 static void smp_notify_keys(struct l2cap_conn *conn)
1021 {
1022 	struct l2cap_chan *chan = conn->smp;
1023 	struct smp_chan *smp = chan->data;
1024 	struct hci_conn *hcon = conn->hcon;
1025 	struct hci_dev *hdev = hcon->hdev;
1026 	struct smp_cmd_pairing *req = (void *) &smp->preq[1];
1027 	struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1];
1028 	bool persistent;
1029 
1030 	if (hcon->type == ACL_LINK) {
1031 		if (hcon->key_type == HCI_LK_DEBUG_COMBINATION)
1032 			persistent = false;
1033 		else
1034 			persistent = !test_bit(HCI_CONN_FLUSH_KEY,
1035 					       &hcon->flags);
1036 	} else {
1037 		/* The LTKs, IRKs and CSRKs should be persistent only if
1038 		 * both sides had the bonding bit set in their
1039 		 * authentication requests.
1040 		 */
1041 		persistent = !!((req->auth_req & rsp->auth_req) &
1042 				SMP_AUTH_BONDING);
1043 	}
1044 
1045 	if (smp->remote_irk) {
1046 		mgmt_new_irk(hdev, smp->remote_irk, persistent);
1047 
1048 		/* Now that user space can be considered to know the
1049 		 * identity address track the connection based on it
1050 		 * from now on (assuming this is an LE link).
1051 		 */
1052 		if (hcon->type == LE_LINK) {
1053 			bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
1054 			hcon->dst_type = smp->remote_irk->addr_type;
1055 			queue_work(hdev->workqueue, &conn->id_addr_update_work);
1056 		}
1057 	}
1058 
1059 	if (smp->csrk) {
1060 		smp->csrk->bdaddr_type = hcon->dst_type;
1061 		bacpy(&smp->csrk->bdaddr, &hcon->dst);
1062 		mgmt_new_csrk(hdev, smp->csrk, persistent);
1063 	}
1064 
1065 	if (smp->slave_csrk) {
1066 		smp->slave_csrk->bdaddr_type = hcon->dst_type;
1067 		bacpy(&smp->slave_csrk->bdaddr, &hcon->dst);
1068 		mgmt_new_csrk(hdev, smp->slave_csrk, persistent);
1069 	}
1070 
1071 	if (smp->ltk) {
1072 		smp->ltk->bdaddr_type = hcon->dst_type;
1073 		bacpy(&smp->ltk->bdaddr, &hcon->dst);
1074 		mgmt_new_ltk(hdev, smp->ltk, persistent);
1075 	}
1076 
1077 	if (smp->slave_ltk) {
1078 		smp->slave_ltk->bdaddr_type = hcon->dst_type;
1079 		bacpy(&smp->slave_ltk->bdaddr, &hcon->dst);
1080 		mgmt_new_ltk(hdev, smp->slave_ltk, persistent);
1081 	}
1082 
1083 	if (smp->link_key) {
1084 		struct link_key *key;
1085 		u8 type;
1086 
1087 		if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1088 			type = HCI_LK_DEBUG_COMBINATION;
1089 		else if (hcon->sec_level == BT_SECURITY_FIPS)
1090 			type = HCI_LK_AUTH_COMBINATION_P256;
1091 		else
1092 			type = HCI_LK_UNAUTH_COMBINATION_P256;
1093 
1094 		key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst,
1095 				       smp->link_key, type, 0, &persistent);
1096 		if (key) {
1097 			mgmt_new_link_key(hdev, key, persistent);
1098 
1099 			/* Don't keep debug keys around if the relevant
1100 			 * flag is not set.
1101 			 */
1102 			if (!hci_dev_test_flag(hdev, HCI_KEEP_DEBUG_KEYS) &&
1103 			    key->type == HCI_LK_DEBUG_COMBINATION) {
1104 				list_del_rcu(&key->list);
1105 				kfree_rcu(key, rcu);
1106 			}
1107 		}
1108 	}
1109 }
1110 
1111 static void sc_add_ltk(struct smp_chan *smp)
1112 {
1113 	struct hci_conn *hcon = smp->conn->hcon;
1114 	u8 key_type, auth;
1115 
1116 	if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1117 		key_type = SMP_LTK_P256_DEBUG;
1118 	else
1119 		key_type = SMP_LTK_P256;
1120 
1121 	if (hcon->pending_sec_level == BT_SECURITY_FIPS)
1122 		auth = 1;
1123 	else
1124 		auth = 0;
1125 
1126 	smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1127 			       key_type, auth, smp->tk, smp->enc_key_size,
1128 			       0, 0);
1129 }
1130 
1131 static void sc_generate_link_key(struct smp_chan *smp)
1132 {
1133 	/* These constants are as specified in the core specification.
1134 	 * In ASCII they spell out to 'tmp1' and 'lebr'.
1135 	 */
1136 	const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 };
1137 	const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c };
1138 
1139 	smp->link_key = kzalloc(16, GFP_KERNEL);
1140 	if (!smp->link_key)
1141 		return;
1142 
1143 	if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) {
1144 		kzfree(smp->link_key);
1145 		smp->link_key = NULL;
1146 		return;
1147 	}
1148 
1149 	if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) {
1150 		kzfree(smp->link_key);
1151 		smp->link_key = NULL;
1152 		return;
1153 	}
1154 }
1155 
1156 static void smp_allow_key_dist(struct smp_chan *smp)
1157 {
1158 	/* Allow the first expected phase 3 PDU. The rest of the PDUs
1159 	 * will be allowed in each PDU handler to ensure we receive
1160 	 * them in the correct order.
1161 	 */
1162 	if (smp->remote_key_dist & SMP_DIST_ENC_KEY)
1163 		SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO);
1164 	else if (smp->remote_key_dist & SMP_DIST_ID_KEY)
1165 		SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
1166 	else if (smp->remote_key_dist & SMP_DIST_SIGN)
1167 		SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
1168 }
1169 
1170 static void sc_generate_ltk(struct smp_chan *smp)
1171 {
1172 	/* These constants are as specified in the core specification.
1173 	 * In ASCII they spell out to 'tmp2' and 'brle'.
1174 	 */
1175 	const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 };
1176 	const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 };
1177 	struct hci_conn *hcon = smp->conn->hcon;
1178 	struct hci_dev *hdev = hcon->hdev;
1179 	struct link_key *key;
1180 
1181 	key = hci_find_link_key(hdev, &hcon->dst);
1182 	if (!key) {
1183 		BT_ERR("%s No Link Key found to generate LTK", hdev->name);
1184 		return;
1185 	}
1186 
1187 	if (key->type == HCI_LK_DEBUG_COMBINATION)
1188 		set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1189 
1190 	if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk))
1191 		return;
1192 
1193 	if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk))
1194 		return;
1195 
1196 	sc_add_ltk(smp);
1197 }
1198 
1199 static void smp_distribute_keys(struct smp_chan *smp)
1200 {
1201 	struct smp_cmd_pairing *req, *rsp;
1202 	struct l2cap_conn *conn = smp->conn;
1203 	struct hci_conn *hcon = conn->hcon;
1204 	struct hci_dev *hdev = hcon->hdev;
1205 	__u8 *keydist;
1206 
1207 	BT_DBG("conn %p", conn);
1208 
1209 	rsp = (void *) &smp->prsp[1];
1210 
1211 	/* The responder sends its keys first */
1212 	if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) {
1213 		smp_allow_key_dist(smp);
1214 		return;
1215 	}
1216 
1217 	req = (void *) &smp->preq[1];
1218 
1219 	if (hcon->out) {
1220 		keydist = &rsp->init_key_dist;
1221 		*keydist &= req->init_key_dist;
1222 	} else {
1223 		keydist = &rsp->resp_key_dist;
1224 		*keydist &= req->resp_key_dist;
1225 	}
1226 
1227 	if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1228 		if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY))
1229 			sc_generate_link_key(smp);
1230 		if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY))
1231 			sc_generate_ltk(smp);
1232 
1233 		/* Clear the keys which are generated but not distributed */
1234 		*keydist &= ~SMP_SC_NO_DIST;
1235 	}
1236 
1237 	BT_DBG("keydist 0x%x", *keydist);
1238 
1239 	if (*keydist & SMP_DIST_ENC_KEY) {
1240 		struct smp_cmd_encrypt_info enc;
1241 		struct smp_cmd_master_ident ident;
1242 		struct smp_ltk *ltk;
1243 		u8 authenticated;
1244 		__le16 ediv;
1245 		__le64 rand;
1246 
1247 		/* Make sure we generate only the significant amount of
1248 		 * bytes based on the encryption key size, and set the rest
1249 		 * of the value to zeroes.
1250 		 */
1251 		get_random_bytes(enc.ltk, smp->enc_key_size);
1252 		memset(enc.ltk + smp->enc_key_size, 0,
1253 		       sizeof(enc.ltk) - smp->enc_key_size);
1254 
1255 		get_random_bytes(&ediv, sizeof(ediv));
1256 		get_random_bytes(&rand, sizeof(rand));
1257 
1258 		smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);
1259 
1260 		authenticated = hcon->sec_level == BT_SECURITY_HIGH;
1261 		ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type,
1262 				  SMP_LTK_SLAVE, authenticated, enc.ltk,
1263 				  smp->enc_key_size, ediv, rand);
1264 		smp->slave_ltk = ltk;
1265 
1266 		ident.ediv = ediv;
1267 		ident.rand = rand;
1268 
1269 		smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident);
1270 
1271 		*keydist &= ~SMP_DIST_ENC_KEY;
1272 	}
1273 
1274 	if (*keydist & SMP_DIST_ID_KEY) {
1275 		struct smp_cmd_ident_addr_info addrinfo;
1276 		struct smp_cmd_ident_info idinfo;
1277 
1278 		memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk));
1279 
1280 		smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);
1281 
1282 		/* The hci_conn contains the local identity address
1283 		 * after the connection has been established.
1284 		 *
1285 		 * This is true even when the connection has been
1286 		 * established using a resolvable random address.
1287 		 */
1288 		bacpy(&addrinfo.bdaddr, &hcon->src);
1289 		addrinfo.addr_type = hcon->src_type;
1290 
1291 		smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo),
1292 			     &addrinfo);
1293 
1294 		*keydist &= ~SMP_DIST_ID_KEY;
1295 	}
1296 
1297 	if (*keydist & SMP_DIST_SIGN) {
1298 		struct smp_cmd_sign_info sign;
1299 		struct smp_csrk *csrk;
1300 
1301 		/* Generate a new random key */
1302 		get_random_bytes(sign.csrk, sizeof(sign.csrk));
1303 
1304 		csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
1305 		if (csrk) {
1306 			if (hcon->sec_level > BT_SECURITY_MEDIUM)
1307 				csrk->type = MGMT_CSRK_LOCAL_AUTHENTICATED;
1308 			else
1309 				csrk->type = MGMT_CSRK_LOCAL_UNAUTHENTICATED;
1310 			memcpy(csrk->val, sign.csrk, sizeof(csrk->val));
1311 		}
1312 		smp->slave_csrk = csrk;
1313 
1314 		smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);
1315 
1316 		*keydist &= ~SMP_DIST_SIGN;
1317 	}
1318 
1319 	/* If there are still keys to be received wait for them */
1320 	if (smp->remote_key_dist & KEY_DIST_MASK) {
1321 		smp_allow_key_dist(smp);
1322 		return;
1323 	}
1324 
1325 	set_bit(SMP_FLAG_COMPLETE, &smp->flags);
1326 	smp_notify_keys(conn);
1327 
1328 	smp_chan_destroy(conn);
1329 }
1330 
1331 static void smp_timeout(struct work_struct *work)
1332 {
1333 	struct smp_chan *smp = container_of(work, struct smp_chan,
1334 					    security_timer.work);
1335 	struct l2cap_conn *conn = smp->conn;
1336 
1337 	BT_DBG("conn %p", conn);
1338 
1339 	hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM);
1340 }
1341 
1342 static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
1343 {
1344 	struct l2cap_chan *chan = conn->smp;
1345 	struct smp_chan *smp;
1346 
1347 	smp = kzalloc(sizeof(*smp), GFP_ATOMIC);
1348 	if (!smp)
1349 		return NULL;
1350 
1351 	smp->tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
1352 	if (IS_ERR(smp->tfm_aes)) {
1353 		BT_ERR("Unable to create AES crypto context");
1354 		kzfree(smp);
1355 		return NULL;
1356 	}
1357 
1358 	smp->tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
1359 	if (IS_ERR(smp->tfm_cmac)) {
1360 		BT_ERR("Unable to create CMAC crypto context");
1361 		crypto_free_cipher(smp->tfm_aes);
1362 		kzfree(smp);
1363 		return NULL;
1364 	}
1365 
1366 	smp->conn = conn;
1367 	chan->data = smp;
1368 
1369 	SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL);
1370 
1371 	INIT_DELAYED_WORK(&smp->security_timer, smp_timeout);
1372 
1373 	hci_conn_hold(conn->hcon);
1374 
1375 	return smp;
1376 }
1377 
1378 static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16])
1379 {
1380 	struct hci_conn *hcon = smp->conn->hcon;
1381 	u8 *na, *nb, a[7], b[7];
1382 
1383 	if (hcon->out) {
1384 		na   = smp->prnd;
1385 		nb   = smp->rrnd;
1386 	} else {
1387 		na   = smp->rrnd;
1388 		nb   = smp->prnd;
1389 	}
1390 
1391 	memcpy(a, &hcon->init_addr, 6);
1392 	memcpy(b, &hcon->resp_addr, 6);
1393 	a[6] = hcon->init_addr_type;
1394 	b[6] = hcon->resp_addr_type;
1395 
1396 	return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk);
1397 }
1398 
1399 static void sc_dhkey_check(struct smp_chan *smp)
1400 {
1401 	struct hci_conn *hcon = smp->conn->hcon;
1402 	struct smp_cmd_dhkey_check check;
1403 	u8 a[7], b[7], *local_addr, *remote_addr;
1404 	u8 io_cap[3], r[16];
1405 
1406 	memcpy(a, &hcon->init_addr, 6);
1407 	memcpy(b, &hcon->resp_addr, 6);
1408 	a[6] = hcon->init_addr_type;
1409 	b[6] = hcon->resp_addr_type;
1410 
1411 	if (hcon->out) {
1412 		local_addr = a;
1413 		remote_addr = b;
1414 		memcpy(io_cap, &smp->preq[1], 3);
1415 	} else {
1416 		local_addr = b;
1417 		remote_addr = a;
1418 		memcpy(io_cap, &smp->prsp[1], 3);
1419 	}
1420 
1421 	memset(r, 0, sizeof(r));
1422 
1423 	if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
1424 		put_unaligned_le32(hcon->passkey_notify, r);
1425 
1426 	if (smp->method == REQ_OOB)
1427 		memcpy(r, smp->rr, 16);
1428 
1429 	smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap,
1430 	       local_addr, remote_addr, check.e);
1431 
1432 	smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check);
1433 }
1434 
1435 static u8 sc_passkey_send_confirm(struct smp_chan *smp)
1436 {
1437 	struct l2cap_conn *conn = smp->conn;
1438 	struct hci_conn *hcon = conn->hcon;
1439 	struct smp_cmd_pairing_confirm cfm;
1440 	u8 r;
1441 
1442 	r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1443 	r |= 0x80;
1444 
1445 	get_random_bytes(smp->prnd, sizeof(smp->prnd));
1446 
1447 	if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r,
1448 		   cfm.confirm_val))
1449 		return SMP_UNSPECIFIED;
1450 
1451 	smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
1452 
1453 	return 0;
1454 }
1455 
1456 static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op)
1457 {
1458 	struct l2cap_conn *conn = smp->conn;
1459 	struct hci_conn *hcon = conn->hcon;
1460 	struct hci_dev *hdev = hcon->hdev;
1461 	u8 cfm[16], r;
1462 
1463 	/* Ignore the PDU if we've already done 20 rounds (0 - 19) */
1464 	if (smp->passkey_round >= 20)
1465 		return 0;
1466 
1467 	switch (smp_op) {
1468 	case SMP_CMD_PAIRING_RANDOM:
1469 		r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1470 		r |= 0x80;
1471 
1472 		if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
1473 			   smp->rrnd, r, cfm))
1474 			return SMP_UNSPECIFIED;
1475 
1476 		if (memcmp(smp->pcnf, cfm, 16))
1477 			return SMP_CONFIRM_FAILED;
1478 
1479 		smp->passkey_round++;
1480 
1481 		if (smp->passkey_round == 20) {
1482 			/* Generate MacKey and LTK */
1483 			if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk))
1484 				return SMP_UNSPECIFIED;
1485 		}
1486 
1487 		/* The round is only complete when the initiator
1488 		 * receives pairing random.
1489 		 */
1490 		if (!hcon->out) {
1491 			smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1492 				     sizeof(smp->prnd), smp->prnd);
1493 			if (smp->passkey_round == 20)
1494 				SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1495 			else
1496 				SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1497 			return 0;
1498 		}
1499 
1500 		/* Start the next round */
1501 		if (smp->passkey_round != 20)
1502 			return sc_passkey_round(smp, 0);
1503 
1504 		/* Passkey rounds are complete - start DHKey Check */
1505 		sc_dhkey_check(smp);
1506 		SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1507 
1508 		break;
1509 
1510 	case SMP_CMD_PAIRING_CONFIRM:
1511 		if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
1512 			set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
1513 			return 0;
1514 		}
1515 
1516 		SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1517 
1518 		if (hcon->out) {
1519 			smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1520 				     sizeof(smp->prnd), smp->prnd);
1521 			return 0;
1522 		}
1523 
1524 		return sc_passkey_send_confirm(smp);
1525 
1526 	case SMP_CMD_PUBLIC_KEY:
1527 	default:
1528 		/* Initiating device starts the round */
1529 		if (!hcon->out)
1530 			return 0;
1531 
1532 		BT_DBG("%s Starting passkey round %u", hdev->name,
1533 		       smp->passkey_round + 1);
1534 
1535 		SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1536 
1537 		return sc_passkey_send_confirm(smp);
1538 	}
1539 
1540 	return 0;
1541 }
1542 
1543 static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey)
1544 {
1545 	struct l2cap_conn *conn = smp->conn;
1546 	struct hci_conn *hcon = conn->hcon;
1547 	u8 smp_op;
1548 
1549 	clear_bit(SMP_FLAG_WAIT_USER, &smp->flags);
1550 
1551 	switch (mgmt_op) {
1552 	case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1553 		smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED);
1554 		return 0;
1555 	case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1556 		smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED);
1557 		return 0;
1558 	case MGMT_OP_USER_PASSKEY_REPLY:
1559 		hcon->passkey_notify = le32_to_cpu(passkey);
1560 		smp->passkey_round = 0;
1561 
1562 		if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags))
1563 			smp_op = SMP_CMD_PAIRING_CONFIRM;
1564 		else
1565 			smp_op = 0;
1566 
1567 		if (sc_passkey_round(smp, smp_op))
1568 			return -EIO;
1569 
1570 		return 0;
1571 	}
1572 
1573 	/* Initiator sends DHKey check first */
1574 	if (hcon->out) {
1575 		sc_dhkey_check(smp);
1576 		SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1577 	} else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) {
1578 		sc_dhkey_check(smp);
1579 		sc_add_ltk(smp);
1580 	}
1581 
1582 	return 0;
1583 }
1584 
1585 int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
1586 {
1587 	struct l2cap_conn *conn = hcon->l2cap_data;
1588 	struct l2cap_chan *chan;
1589 	struct smp_chan *smp;
1590 	u32 value;
1591 	int err;
1592 
1593 	BT_DBG("");
1594 
1595 	if (!conn)
1596 		return -ENOTCONN;
1597 
1598 	chan = conn->smp;
1599 	if (!chan)
1600 		return -ENOTCONN;
1601 
1602 	l2cap_chan_lock(chan);
1603 	if (!chan->data) {
1604 		err = -ENOTCONN;
1605 		goto unlock;
1606 	}
1607 
1608 	smp = chan->data;
1609 
1610 	if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1611 		err = sc_user_reply(smp, mgmt_op, passkey);
1612 		goto unlock;
1613 	}
1614 
1615 	switch (mgmt_op) {
1616 	case MGMT_OP_USER_PASSKEY_REPLY:
1617 		value = le32_to_cpu(passkey);
1618 		memset(smp->tk, 0, sizeof(smp->tk));
1619 		BT_DBG("PassKey: %d", value);
1620 		put_unaligned_le32(value, smp->tk);
1621 		/* Fall Through */
1622 	case MGMT_OP_USER_CONFIRM_REPLY:
1623 		set_bit(SMP_FLAG_TK_VALID, &smp->flags);
1624 		break;
1625 	case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1626 	case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1627 		smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1628 		err = 0;
1629 		goto unlock;
1630 	default:
1631 		smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1632 		err = -EOPNOTSUPP;
1633 		goto unlock;
1634 	}
1635 
1636 	err = 0;
1637 
1638 	/* If it is our turn to send Pairing Confirm, do so now */
1639 	if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) {
1640 		u8 rsp = smp_confirm(smp);
1641 		if (rsp)
1642 			smp_failure(conn, rsp);
1643 	}
1644 
1645 unlock:
1646 	l2cap_chan_unlock(chan);
1647 	return err;
1648 }
1649 
1650 static void build_bredr_pairing_cmd(struct smp_chan *smp,
1651 				    struct smp_cmd_pairing *req,
1652 				    struct smp_cmd_pairing *rsp)
1653 {
1654 	struct l2cap_conn *conn = smp->conn;
1655 	struct hci_dev *hdev = conn->hcon->hdev;
1656 	u8 local_dist = 0, remote_dist = 0;
1657 
1658 	if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
1659 		local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1660 		remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1661 	}
1662 
1663 	if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
1664 		remote_dist |= SMP_DIST_ID_KEY;
1665 
1666 	if (hci_dev_test_flag(hdev, HCI_PRIVACY))
1667 		local_dist |= SMP_DIST_ID_KEY;
1668 
1669 	if (!rsp) {
1670 		memset(req, 0, sizeof(*req));
1671 
1672 		req->init_key_dist   = local_dist;
1673 		req->resp_key_dist   = remote_dist;
1674 		req->max_key_size    = conn->hcon->enc_key_size;
1675 
1676 		smp->remote_key_dist = remote_dist;
1677 
1678 		return;
1679 	}
1680 
1681 	memset(rsp, 0, sizeof(*rsp));
1682 
1683 	rsp->max_key_size    = conn->hcon->enc_key_size;
1684 	rsp->init_key_dist   = req->init_key_dist & remote_dist;
1685 	rsp->resp_key_dist   = req->resp_key_dist & local_dist;
1686 
1687 	smp->remote_key_dist = rsp->init_key_dist;
1688 }
1689 
1690 static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
1691 {
1692 	struct smp_cmd_pairing rsp, *req = (void *) skb->data;
1693 	struct l2cap_chan *chan = conn->smp;
1694 	struct hci_dev *hdev = conn->hcon->hdev;
1695 	struct smp_chan *smp;
1696 	u8 key_size, auth, sec_level;
1697 	int ret;
1698 
1699 	BT_DBG("conn %p", conn);
1700 
1701 	if (skb->len < sizeof(*req))
1702 		return SMP_INVALID_PARAMS;
1703 
1704 	if (conn->hcon->role != HCI_ROLE_SLAVE)
1705 		return SMP_CMD_NOTSUPP;
1706 
1707 	if (!chan->data)
1708 		smp = smp_chan_create(conn);
1709 	else
1710 		smp = chan->data;
1711 
1712 	if (!smp)
1713 		return SMP_UNSPECIFIED;
1714 
1715 	/* We didn't start the pairing, so match remote */
1716 	auth = req->auth_req & AUTH_REQ_MASK(hdev);
1717 
1718 	if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
1719 	    (auth & SMP_AUTH_BONDING))
1720 		return SMP_PAIRING_NOTSUPP;
1721 
1722 	if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1723 		return SMP_AUTH_REQUIREMENTS;
1724 
1725 	smp->preq[0] = SMP_CMD_PAIRING_REQ;
1726 	memcpy(&smp->preq[1], req, sizeof(*req));
1727 	skb_pull(skb, sizeof(*req));
1728 
1729 	/* If the remote side's OOB flag is set it means it has
1730 	 * successfully received our local OOB data - therefore set the
1731 	 * flag to indicate that local OOB is in use.
1732 	 */
1733 	if (req->oob_flag == SMP_OOB_PRESENT)
1734 		set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1735 
1736 	/* SMP over BR/EDR requires special treatment */
1737 	if (conn->hcon->type == ACL_LINK) {
1738 		/* We must have a BR/EDR SC link */
1739 		if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) &&
1740 		    !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
1741 			return SMP_CROSS_TRANSP_NOT_ALLOWED;
1742 
1743 		set_bit(SMP_FLAG_SC, &smp->flags);
1744 
1745 		build_bredr_pairing_cmd(smp, req, &rsp);
1746 
1747 		key_size = min(req->max_key_size, rsp.max_key_size);
1748 		if (check_enc_key_size(conn, key_size))
1749 			return SMP_ENC_KEY_SIZE;
1750 
1751 		/* Clear bits which are generated but not distributed */
1752 		smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1753 
1754 		smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1755 		memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1756 		smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1757 
1758 		smp_distribute_keys(smp);
1759 		return 0;
1760 	}
1761 
1762 	build_pairing_cmd(conn, req, &rsp, auth);
1763 
1764 	if (rsp.auth_req & SMP_AUTH_SC)
1765 		set_bit(SMP_FLAG_SC, &smp->flags);
1766 
1767 	if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
1768 		sec_level = BT_SECURITY_MEDIUM;
1769 	else
1770 		sec_level = authreq_to_seclevel(auth);
1771 
1772 	if (sec_level > conn->hcon->pending_sec_level)
1773 		conn->hcon->pending_sec_level = sec_level;
1774 
1775 	/* If we need MITM check that it can be achieved */
1776 	if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1777 		u8 method;
1778 
1779 		method = get_auth_method(smp, conn->hcon->io_capability,
1780 					 req->io_capability);
1781 		if (method == JUST_WORKS || method == JUST_CFM)
1782 			return SMP_AUTH_REQUIREMENTS;
1783 	}
1784 
1785 	key_size = min(req->max_key_size, rsp.max_key_size);
1786 	if (check_enc_key_size(conn, key_size))
1787 		return SMP_ENC_KEY_SIZE;
1788 
1789 	get_random_bytes(smp->prnd, sizeof(smp->prnd));
1790 
1791 	smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1792 	memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1793 
1794 	smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1795 
1796 	clear_bit(SMP_FLAG_INITIATOR, &smp->flags);
1797 
1798 	/* Strictly speaking we shouldn't allow Pairing Confirm for the
1799 	 * SC case, however some implementations incorrectly copy RFU auth
1800 	 * req bits from our security request, which may create a false
1801 	 * positive SC enablement.
1802 	 */
1803 	SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1804 
1805 	if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1806 		SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
1807 		/* Clear bits which are generated but not distributed */
1808 		smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1809 		/* Wait for Public Key from Initiating Device */
1810 		return 0;
1811 	}
1812 
1813 	/* Request setup of TK */
1814 	ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability);
1815 	if (ret)
1816 		return SMP_UNSPECIFIED;
1817 
1818 	return 0;
1819 }
1820 
1821 static u8 sc_send_public_key(struct smp_chan *smp)
1822 {
1823 	struct hci_dev *hdev = smp->conn->hcon->hdev;
1824 
1825 	BT_DBG("");
1826 
1827 	if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) {
1828 		struct l2cap_chan *chan = hdev->smp_data;
1829 		struct smp_dev *smp_dev;
1830 
1831 		if (!chan || !chan->data)
1832 			return SMP_UNSPECIFIED;
1833 
1834 		smp_dev = chan->data;
1835 
1836 		memcpy(smp->local_pk, smp_dev->local_pk, 64);
1837 		memcpy(smp->local_sk, smp_dev->local_sk, 32);
1838 		memcpy(smp->lr, smp_dev->local_rand, 16);
1839 
1840 		if (smp_dev->debug_key)
1841 			set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1842 
1843 		goto done;
1844 	}
1845 
1846 	if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
1847 		BT_DBG("Using debug keys");
1848 		memcpy(smp->local_pk, debug_pk, 64);
1849 		memcpy(smp->local_sk, debug_sk, 32);
1850 		set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1851 	} else {
1852 		while (true) {
1853 			/* Generate local key pair for Secure Connections */
1854 			if (!ecc_make_key(smp->local_pk, smp->local_sk))
1855 				return SMP_UNSPECIFIED;
1856 
1857 			/* This is unlikely, but we need to check that
1858 			 * we didn't accidentially generate a debug key.
1859 			 */
1860 			if (memcmp(smp->local_sk, debug_sk, 32))
1861 				break;
1862 		}
1863 	}
1864 
1865 done:
1866 	SMP_DBG("Local Public Key X: %32phN", smp->local_pk);
1867 	SMP_DBG("Local Public Key Y: %32phN", smp->local_pk + 32);
1868 	SMP_DBG("Local Private Key:  %32phN", smp->local_sk);
1869 
1870 	smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk);
1871 
1872 	return 0;
1873 }
1874 
1875 static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
1876 {
1877 	struct smp_cmd_pairing *req, *rsp = (void *) skb->data;
1878 	struct l2cap_chan *chan = conn->smp;
1879 	struct smp_chan *smp = chan->data;
1880 	struct hci_dev *hdev = conn->hcon->hdev;
1881 	u8 key_size, auth;
1882 	int ret;
1883 
1884 	BT_DBG("conn %p", conn);
1885 
1886 	if (skb->len < sizeof(*rsp))
1887 		return SMP_INVALID_PARAMS;
1888 
1889 	if (conn->hcon->role != HCI_ROLE_MASTER)
1890 		return SMP_CMD_NOTSUPP;
1891 
1892 	skb_pull(skb, sizeof(*rsp));
1893 
1894 	req = (void *) &smp->preq[1];
1895 
1896 	key_size = min(req->max_key_size, rsp->max_key_size);
1897 	if (check_enc_key_size(conn, key_size))
1898 		return SMP_ENC_KEY_SIZE;
1899 
1900 	auth = rsp->auth_req & AUTH_REQ_MASK(hdev);
1901 
1902 	if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1903 		return SMP_AUTH_REQUIREMENTS;
1904 
1905 	/* If the remote side's OOB flag is set it means it has
1906 	 * successfully received our local OOB data - therefore set the
1907 	 * flag to indicate that local OOB is in use.
1908 	 */
1909 	if (rsp->oob_flag == SMP_OOB_PRESENT)
1910 		set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1911 
1912 	smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1913 	memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
1914 
1915 	/* Update remote key distribution in case the remote cleared
1916 	 * some bits that we had enabled in our request.
1917 	 */
1918 	smp->remote_key_dist &= rsp->resp_key_dist;
1919 
1920 	/* For BR/EDR this means we're done and can start phase 3 */
1921 	if (conn->hcon->type == ACL_LINK) {
1922 		/* Clear bits which are generated but not distributed */
1923 		smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1924 		smp_distribute_keys(smp);
1925 		return 0;
1926 	}
1927 
1928 	if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC))
1929 		set_bit(SMP_FLAG_SC, &smp->flags);
1930 	else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH)
1931 		conn->hcon->pending_sec_level = BT_SECURITY_HIGH;
1932 
1933 	/* If we need MITM check that it can be achieved */
1934 	if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1935 		u8 method;
1936 
1937 		method = get_auth_method(smp, req->io_capability,
1938 					 rsp->io_capability);
1939 		if (method == JUST_WORKS || method == JUST_CFM)
1940 			return SMP_AUTH_REQUIREMENTS;
1941 	}
1942 
1943 	get_random_bytes(smp->prnd, sizeof(smp->prnd));
1944 
1945 	/* Update remote key distribution in case the remote cleared
1946 	 * some bits that we had enabled in our request.
1947 	 */
1948 	smp->remote_key_dist &= rsp->resp_key_dist;
1949 
1950 	if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1951 		/* Clear bits which are generated but not distributed */
1952 		smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1953 		SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
1954 		return sc_send_public_key(smp);
1955 	}
1956 
1957 	auth |= req->auth_req;
1958 
1959 	ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability);
1960 	if (ret)
1961 		return SMP_UNSPECIFIED;
1962 
1963 	set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
1964 
1965 	/* Can't compose response until we have been confirmed */
1966 	if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
1967 		return smp_confirm(smp);
1968 
1969 	return 0;
1970 }
1971 
1972 static u8 sc_check_confirm(struct smp_chan *smp)
1973 {
1974 	struct l2cap_conn *conn = smp->conn;
1975 
1976 	BT_DBG("");
1977 
1978 	if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
1979 		return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM);
1980 
1981 	if (conn->hcon->out) {
1982 		smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1983 			     smp->prnd);
1984 		SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1985 	}
1986 
1987 	return 0;
1988 }
1989 
1990 /* Work-around for some implementations that incorrectly copy RFU bits
1991  * from our security request and thereby create the impression that
1992  * we're doing SC when in fact the remote doesn't support it.
1993  */
1994 static int fixup_sc_false_positive(struct smp_chan *smp)
1995 {
1996 	struct l2cap_conn *conn = smp->conn;
1997 	struct hci_conn *hcon = conn->hcon;
1998 	struct hci_dev *hdev = hcon->hdev;
1999 	struct smp_cmd_pairing *req, *rsp;
2000 	u8 auth;
2001 
2002 	/* The issue is only observed when we're in slave role */
2003 	if (hcon->out)
2004 		return SMP_UNSPECIFIED;
2005 
2006 	if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) {
2007 		BT_ERR("Refusing SMP SC -> legacy fallback in SC-only mode");
2008 		return SMP_UNSPECIFIED;
2009 	}
2010 
2011 	BT_ERR("Trying to fall back to legacy SMP");
2012 
2013 	req = (void *) &smp->preq[1];
2014 	rsp = (void *) &smp->prsp[1];
2015 
2016 	/* Rebuild key dist flags which may have been cleared for SC */
2017 	smp->remote_key_dist = (req->init_key_dist & rsp->resp_key_dist);
2018 
2019 	auth = req->auth_req & AUTH_REQ_MASK(hdev);
2020 
2021 	if (tk_request(conn, 0, auth, rsp->io_capability, req->io_capability)) {
2022 		BT_ERR("Failed to fall back to legacy SMP");
2023 		return SMP_UNSPECIFIED;
2024 	}
2025 
2026 	clear_bit(SMP_FLAG_SC, &smp->flags);
2027 
2028 	return 0;
2029 }
2030 
2031 static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
2032 {
2033 	struct l2cap_chan *chan = conn->smp;
2034 	struct smp_chan *smp = chan->data;
2035 
2036 	BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
2037 
2038 	if (skb->len < sizeof(smp->pcnf))
2039 		return SMP_INVALID_PARAMS;
2040 
2041 	memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
2042 	skb_pull(skb, sizeof(smp->pcnf));
2043 
2044 	if (test_bit(SMP_FLAG_SC, &smp->flags)) {
2045 		int ret;
2046 
2047 		/* Public Key exchange must happen before any other steps */
2048 		if (test_bit(SMP_FLAG_REMOTE_PK, &smp->flags))
2049 			return sc_check_confirm(smp);
2050 
2051 		BT_ERR("Unexpected SMP Pairing Confirm");
2052 
2053 		ret = fixup_sc_false_positive(smp);
2054 		if (ret)
2055 			return ret;
2056 	}
2057 
2058 	if (conn->hcon->out) {
2059 		smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2060 			     smp->prnd);
2061 		SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2062 		return 0;
2063 	}
2064 
2065 	if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
2066 		return smp_confirm(smp);
2067 
2068 	set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
2069 
2070 	return 0;
2071 }
2072 
2073 static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
2074 {
2075 	struct l2cap_chan *chan = conn->smp;
2076 	struct smp_chan *smp = chan->data;
2077 	struct hci_conn *hcon = conn->hcon;
2078 	u8 *pkax, *pkbx, *na, *nb;
2079 	u32 passkey;
2080 	int err;
2081 
2082 	BT_DBG("conn %p", conn);
2083 
2084 	if (skb->len < sizeof(smp->rrnd))
2085 		return SMP_INVALID_PARAMS;
2086 
2087 	memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd));
2088 	skb_pull(skb, sizeof(smp->rrnd));
2089 
2090 	if (!test_bit(SMP_FLAG_SC, &smp->flags))
2091 		return smp_random(smp);
2092 
2093 	if (hcon->out) {
2094 		pkax = smp->local_pk;
2095 		pkbx = smp->remote_pk;
2096 		na   = smp->prnd;
2097 		nb   = smp->rrnd;
2098 	} else {
2099 		pkax = smp->remote_pk;
2100 		pkbx = smp->local_pk;
2101 		na   = smp->rrnd;
2102 		nb   = smp->prnd;
2103 	}
2104 
2105 	if (smp->method == REQ_OOB) {
2106 		if (!hcon->out)
2107 			smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2108 				     sizeof(smp->prnd), smp->prnd);
2109 		SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2110 		goto mackey_and_ltk;
2111 	}
2112 
2113 	/* Passkey entry has special treatment */
2114 	if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2115 		return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM);
2116 
2117 	if (hcon->out) {
2118 		u8 cfm[16];
2119 
2120 		err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
2121 			     smp->rrnd, 0, cfm);
2122 		if (err)
2123 			return SMP_UNSPECIFIED;
2124 
2125 		if (memcmp(smp->pcnf, cfm, 16))
2126 			return SMP_CONFIRM_FAILED;
2127 	} else {
2128 		smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2129 			     smp->prnd);
2130 		SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2131 	}
2132 
2133 mackey_and_ltk:
2134 	/* Generate MacKey and LTK */
2135 	err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk);
2136 	if (err)
2137 		return SMP_UNSPECIFIED;
2138 
2139 	if (smp->method == JUST_WORKS || smp->method == REQ_OOB) {
2140 		if (hcon->out) {
2141 			sc_dhkey_check(smp);
2142 			SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2143 		}
2144 		return 0;
2145 	}
2146 
2147 	err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);
2148 	if (err)
2149 		return SMP_UNSPECIFIED;
2150 
2151 	err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type,
2152 					hcon->dst_type, passkey, 0);
2153 	if (err)
2154 		return SMP_UNSPECIFIED;
2155 
2156 	set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2157 
2158 	return 0;
2159 }
2160 
2161 static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
2162 {
2163 	struct smp_ltk *key;
2164 	struct hci_conn *hcon = conn->hcon;
2165 
2166 	key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role);
2167 	if (!key)
2168 		return false;
2169 
2170 	if (smp_ltk_sec_level(key) < sec_level)
2171 		return false;
2172 
2173 	if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
2174 		return true;
2175 
2176 	hci_le_start_enc(hcon, key->ediv, key->rand, key->val, key->enc_size);
2177 	hcon->enc_key_size = key->enc_size;
2178 
2179 	/* We never store STKs for master role, so clear this flag */
2180 	clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
2181 
2182 	return true;
2183 }
2184 
2185 bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level,
2186 			     enum smp_key_pref key_pref)
2187 {
2188 	if (sec_level == BT_SECURITY_LOW)
2189 		return true;
2190 
2191 	/* If we're encrypted with an STK but the caller prefers using
2192 	 * LTK claim insufficient security. This way we allow the
2193 	 * connection to be re-encrypted with an LTK, even if the LTK
2194 	 * provides the same level of security. Only exception is if we
2195 	 * don't have an LTK (e.g. because of key distribution bits).
2196 	 */
2197 	if (key_pref == SMP_USE_LTK &&
2198 	    test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) &&
2199 	    hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role))
2200 		return false;
2201 
2202 	if (hcon->sec_level >= sec_level)
2203 		return true;
2204 
2205 	return false;
2206 }
2207 
2208 static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
2209 {
2210 	struct smp_cmd_security_req *rp = (void *) skb->data;
2211 	struct smp_cmd_pairing cp;
2212 	struct hci_conn *hcon = conn->hcon;
2213 	struct hci_dev *hdev = hcon->hdev;
2214 	struct smp_chan *smp;
2215 	u8 sec_level, auth;
2216 
2217 	BT_DBG("conn %p", conn);
2218 
2219 	if (skb->len < sizeof(*rp))
2220 		return SMP_INVALID_PARAMS;
2221 
2222 	if (hcon->role != HCI_ROLE_MASTER)
2223 		return SMP_CMD_NOTSUPP;
2224 
2225 	auth = rp->auth_req & AUTH_REQ_MASK(hdev);
2226 
2227 	if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
2228 		return SMP_AUTH_REQUIREMENTS;
2229 
2230 	if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
2231 		sec_level = BT_SECURITY_MEDIUM;
2232 	else
2233 		sec_level = authreq_to_seclevel(auth);
2234 
2235 	if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
2236 		return 0;
2237 
2238 	if (sec_level > hcon->pending_sec_level)
2239 		hcon->pending_sec_level = sec_level;
2240 
2241 	if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2242 		return 0;
2243 
2244 	smp = smp_chan_create(conn);
2245 	if (!smp)
2246 		return SMP_UNSPECIFIED;
2247 
2248 	if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
2249 	    (auth & SMP_AUTH_BONDING))
2250 		return SMP_PAIRING_NOTSUPP;
2251 
2252 	skb_pull(skb, sizeof(*rp));
2253 
2254 	memset(&cp, 0, sizeof(cp));
2255 	build_pairing_cmd(conn, &cp, NULL, auth);
2256 
2257 	smp->preq[0] = SMP_CMD_PAIRING_REQ;
2258 	memcpy(&smp->preq[1], &cp, sizeof(cp));
2259 
2260 	smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2261 	SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2262 
2263 	return 0;
2264 }
2265 
2266 int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
2267 {
2268 	struct l2cap_conn *conn = hcon->l2cap_data;
2269 	struct l2cap_chan *chan;
2270 	struct smp_chan *smp;
2271 	__u8 authreq;
2272 	int ret;
2273 
2274 	BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);
2275 
2276 	/* This may be NULL if there's an unexpected disconnection */
2277 	if (!conn)
2278 		return 1;
2279 
2280 	if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED))
2281 		return 1;
2282 
2283 	if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
2284 		return 1;
2285 
2286 	if (sec_level > hcon->pending_sec_level)
2287 		hcon->pending_sec_level = sec_level;
2288 
2289 	if (hcon->role == HCI_ROLE_MASTER)
2290 		if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2291 			return 0;
2292 
2293 	chan = conn->smp;
2294 	if (!chan) {
2295 		BT_ERR("SMP security requested but not available");
2296 		return 1;
2297 	}
2298 
2299 	l2cap_chan_lock(chan);
2300 
2301 	/* If SMP is already in progress ignore this request */
2302 	if (chan->data) {
2303 		ret = 0;
2304 		goto unlock;
2305 	}
2306 
2307 	smp = smp_chan_create(conn);
2308 	if (!smp) {
2309 		ret = 1;
2310 		goto unlock;
2311 	}
2312 
2313 	authreq = seclevel_to_authreq(sec_level);
2314 
2315 	if (hci_dev_test_flag(hcon->hdev, HCI_SC_ENABLED))
2316 		authreq |= SMP_AUTH_SC;
2317 
2318 	/* Require MITM if IO Capability allows or the security level
2319 	 * requires it.
2320 	 */
2321 	if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT ||
2322 	    hcon->pending_sec_level > BT_SECURITY_MEDIUM)
2323 		authreq |= SMP_AUTH_MITM;
2324 
2325 	if (hcon->role == HCI_ROLE_MASTER) {
2326 		struct smp_cmd_pairing cp;
2327 
2328 		build_pairing_cmd(conn, &cp, NULL, authreq);
2329 		smp->preq[0] = SMP_CMD_PAIRING_REQ;
2330 		memcpy(&smp->preq[1], &cp, sizeof(cp));
2331 
2332 		smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2333 		SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2334 	} else {
2335 		struct smp_cmd_security_req cp;
2336 		cp.auth_req = authreq;
2337 		smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
2338 		SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ);
2339 	}
2340 
2341 	set_bit(SMP_FLAG_INITIATOR, &smp->flags);
2342 	ret = 0;
2343 
2344 unlock:
2345 	l2cap_chan_unlock(chan);
2346 	return ret;
2347 }
2348 
2349 void smp_cancel_pairing(struct hci_conn *hcon)
2350 {
2351 	struct l2cap_conn *conn = hcon->l2cap_data;
2352 	struct l2cap_chan *chan;
2353 	struct smp_chan *smp;
2354 
2355 	if (!conn)
2356 		return;
2357 
2358 	chan = conn->smp;
2359 	if (!chan)
2360 		return;
2361 
2362 	l2cap_chan_lock(chan);
2363 
2364 	smp = chan->data;
2365 	if (smp) {
2366 		if (test_bit(SMP_FLAG_COMPLETE, &smp->flags))
2367 			smp_failure(conn, 0);
2368 		else
2369 			smp_failure(conn, SMP_UNSPECIFIED);
2370 	}
2371 
2372 	l2cap_chan_unlock(chan);
2373 }
2374 
2375 static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb)
2376 {
2377 	struct smp_cmd_encrypt_info *rp = (void *) skb->data;
2378 	struct l2cap_chan *chan = conn->smp;
2379 	struct smp_chan *smp = chan->data;
2380 
2381 	BT_DBG("conn %p", conn);
2382 
2383 	if (skb->len < sizeof(*rp))
2384 		return SMP_INVALID_PARAMS;
2385 
2386 	SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT);
2387 
2388 	skb_pull(skb, sizeof(*rp));
2389 
2390 	memcpy(smp->tk, rp->ltk, sizeof(smp->tk));
2391 
2392 	return 0;
2393 }
2394 
2395 static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
2396 {
2397 	struct smp_cmd_master_ident *rp = (void *) skb->data;
2398 	struct l2cap_chan *chan = conn->smp;
2399 	struct smp_chan *smp = chan->data;
2400 	struct hci_dev *hdev = conn->hcon->hdev;
2401 	struct hci_conn *hcon = conn->hcon;
2402 	struct smp_ltk *ltk;
2403 	u8 authenticated;
2404 
2405 	BT_DBG("conn %p", conn);
2406 
2407 	if (skb->len < sizeof(*rp))
2408 		return SMP_INVALID_PARAMS;
2409 
2410 	/* Mark the information as received */
2411 	smp->remote_key_dist &= ~SMP_DIST_ENC_KEY;
2412 
2413 	if (smp->remote_key_dist & SMP_DIST_ID_KEY)
2414 		SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
2415 	else if (smp->remote_key_dist & SMP_DIST_SIGN)
2416 		SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2417 
2418 	skb_pull(skb, sizeof(*rp));
2419 
2420 	authenticated = (hcon->sec_level == BT_SECURITY_HIGH);
2421 	ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK,
2422 			  authenticated, smp->tk, smp->enc_key_size,
2423 			  rp->ediv, rp->rand);
2424 	smp->ltk = ltk;
2425 	if (!(smp->remote_key_dist & KEY_DIST_MASK))
2426 		smp_distribute_keys(smp);
2427 
2428 	return 0;
2429 }
2430 
2431 static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb)
2432 {
2433 	struct smp_cmd_ident_info *info = (void *) skb->data;
2434 	struct l2cap_chan *chan = conn->smp;
2435 	struct smp_chan *smp = chan->data;
2436 
2437 	BT_DBG("");
2438 
2439 	if (skb->len < sizeof(*info))
2440 		return SMP_INVALID_PARAMS;
2441 
2442 	SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO);
2443 
2444 	skb_pull(skb, sizeof(*info));
2445 
2446 	memcpy(smp->irk, info->irk, 16);
2447 
2448 	return 0;
2449 }
2450 
2451 static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,
2452 				   struct sk_buff *skb)
2453 {
2454 	struct smp_cmd_ident_addr_info *info = (void *) skb->data;
2455 	struct l2cap_chan *chan = conn->smp;
2456 	struct smp_chan *smp = chan->data;
2457 	struct hci_conn *hcon = conn->hcon;
2458 	bdaddr_t rpa;
2459 
2460 	BT_DBG("");
2461 
2462 	if (skb->len < sizeof(*info))
2463 		return SMP_INVALID_PARAMS;
2464 
2465 	/* Mark the information as received */
2466 	smp->remote_key_dist &= ~SMP_DIST_ID_KEY;
2467 
2468 	if (smp->remote_key_dist & SMP_DIST_SIGN)
2469 		SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2470 
2471 	skb_pull(skb, sizeof(*info));
2472 
2473 	/* Strictly speaking the Core Specification (4.1) allows sending
2474 	 * an empty address which would force us to rely on just the IRK
2475 	 * as "identity information". However, since such
2476 	 * implementations are not known of and in order to not over
2477 	 * complicate our implementation, simply pretend that we never
2478 	 * received an IRK for such a device.
2479 	 *
2480 	 * The Identity Address must also be a Static Random or Public
2481 	 * Address, which hci_is_identity_address() checks for.
2482 	 */
2483 	if (!bacmp(&info->bdaddr, BDADDR_ANY) ||
2484 	    !hci_is_identity_address(&info->bdaddr, info->addr_type)) {
2485 		BT_ERR("Ignoring IRK with no identity address");
2486 		goto distribute;
2487 	}
2488 
2489 	bacpy(&smp->id_addr, &info->bdaddr);
2490 	smp->id_addr_type = info->addr_type;
2491 
2492 	if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type))
2493 		bacpy(&rpa, &hcon->dst);
2494 	else
2495 		bacpy(&rpa, BDADDR_ANY);
2496 
2497 	smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr,
2498 				      smp->id_addr_type, smp->irk, &rpa);
2499 
2500 distribute:
2501 	if (!(smp->remote_key_dist & KEY_DIST_MASK))
2502 		smp_distribute_keys(smp);
2503 
2504 	return 0;
2505 }
2506 
2507 static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb)
2508 {
2509 	struct smp_cmd_sign_info *rp = (void *) skb->data;
2510 	struct l2cap_chan *chan = conn->smp;
2511 	struct smp_chan *smp = chan->data;
2512 	struct smp_csrk *csrk;
2513 
2514 	BT_DBG("conn %p", conn);
2515 
2516 	if (skb->len < sizeof(*rp))
2517 		return SMP_INVALID_PARAMS;
2518 
2519 	/* Mark the information as received */
2520 	smp->remote_key_dist &= ~SMP_DIST_SIGN;
2521 
2522 	skb_pull(skb, sizeof(*rp));
2523 
2524 	csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
2525 	if (csrk) {
2526 		if (conn->hcon->sec_level > BT_SECURITY_MEDIUM)
2527 			csrk->type = MGMT_CSRK_REMOTE_AUTHENTICATED;
2528 		else
2529 			csrk->type = MGMT_CSRK_REMOTE_UNAUTHENTICATED;
2530 		memcpy(csrk->val, rp->csrk, sizeof(csrk->val));
2531 	}
2532 	smp->csrk = csrk;
2533 	smp_distribute_keys(smp);
2534 
2535 	return 0;
2536 }
2537 
2538 static u8 sc_select_method(struct smp_chan *smp)
2539 {
2540 	struct l2cap_conn *conn = smp->conn;
2541 	struct hci_conn *hcon = conn->hcon;
2542 	struct smp_cmd_pairing *local, *remote;
2543 	u8 local_mitm, remote_mitm, local_io, remote_io, method;
2544 
2545 	if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags) ||
2546 	    test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags))
2547 		return REQ_OOB;
2548 
2549 	/* The preq/prsp contain the raw Pairing Request/Response PDUs
2550 	 * which are needed as inputs to some crypto functions. To get
2551 	 * the "struct smp_cmd_pairing" from them we need to skip the
2552 	 * first byte which contains the opcode.
2553 	 */
2554 	if (hcon->out) {
2555 		local = (void *) &smp->preq[1];
2556 		remote = (void *) &smp->prsp[1];
2557 	} else {
2558 		local = (void *) &smp->prsp[1];
2559 		remote = (void *) &smp->preq[1];
2560 	}
2561 
2562 	local_io = local->io_capability;
2563 	remote_io = remote->io_capability;
2564 
2565 	local_mitm = (local->auth_req & SMP_AUTH_MITM);
2566 	remote_mitm = (remote->auth_req & SMP_AUTH_MITM);
2567 
2568 	/* If either side wants MITM, look up the method from the table,
2569 	 * otherwise use JUST WORKS.
2570 	 */
2571 	if (local_mitm || remote_mitm)
2572 		method = get_auth_method(smp, local_io, remote_io);
2573 	else
2574 		method = JUST_WORKS;
2575 
2576 	/* Don't confirm locally initiated pairing attempts */
2577 	if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags))
2578 		method = JUST_WORKS;
2579 
2580 	return method;
2581 }
2582 
2583 static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb)
2584 {
2585 	struct smp_cmd_public_key *key = (void *) skb->data;
2586 	struct hci_conn *hcon = conn->hcon;
2587 	struct l2cap_chan *chan = conn->smp;
2588 	struct smp_chan *smp = chan->data;
2589 	struct hci_dev *hdev = hcon->hdev;
2590 	struct smp_cmd_pairing_confirm cfm;
2591 	int err;
2592 
2593 	BT_DBG("conn %p", conn);
2594 
2595 	if (skb->len < sizeof(*key))
2596 		return SMP_INVALID_PARAMS;
2597 
2598 	memcpy(smp->remote_pk, key, 64);
2599 
2600 	if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags)) {
2601 		err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk,
2602 			     smp->rr, 0, cfm.confirm_val);
2603 		if (err)
2604 			return SMP_UNSPECIFIED;
2605 
2606 		if (memcmp(cfm.confirm_val, smp->pcnf, 16))
2607 			return SMP_CONFIRM_FAILED;
2608 	}
2609 
2610 	/* Non-initiating device sends its public key after receiving
2611 	 * the key from the initiating device.
2612 	 */
2613 	if (!hcon->out) {
2614 		err = sc_send_public_key(smp);
2615 		if (err)
2616 			return err;
2617 	}
2618 
2619 	SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk);
2620 	SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32);
2621 
2622 	if (!ecdh_shared_secret(smp->remote_pk, smp->local_sk, smp->dhkey))
2623 		return SMP_UNSPECIFIED;
2624 
2625 	SMP_DBG("DHKey %32phN", smp->dhkey);
2626 
2627 	set_bit(SMP_FLAG_REMOTE_PK, &smp->flags);
2628 
2629 	smp->method = sc_select_method(smp);
2630 
2631 	BT_DBG("%s selected method 0x%02x", hdev->name, smp->method);
2632 
2633 	/* JUST_WORKS and JUST_CFM result in an unauthenticated key */
2634 	if (smp->method == JUST_WORKS || smp->method == JUST_CFM)
2635 		hcon->pending_sec_level = BT_SECURITY_MEDIUM;
2636 	else
2637 		hcon->pending_sec_level = BT_SECURITY_FIPS;
2638 
2639 	if (!memcmp(debug_pk, smp->remote_pk, 64))
2640 		set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
2641 
2642 	if (smp->method == DSP_PASSKEY) {
2643 		get_random_bytes(&hcon->passkey_notify,
2644 				 sizeof(hcon->passkey_notify));
2645 		hcon->passkey_notify %= 1000000;
2646 		hcon->passkey_entered = 0;
2647 		smp->passkey_round = 0;
2648 		if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type,
2649 					     hcon->dst_type,
2650 					     hcon->passkey_notify,
2651 					     hcon->passkey_entered))
2652 			return SMP_UNSPECIFIED;
2653 		SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2654 		return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY);
2655 	}
2656 
2657 	if (smp->method == REQ_OOB) {
2658 		if (hcon->out)
2659 			smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2660 				     sizeof(smp->prnd), smp->prnd);
2661 
2662 		SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2663 
2664 		return 0;
2665 	}
2666 
2667 	if (hcon->out)
2668 		SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2669 
2670 	if (smp->method == REQ_PASSKEY) {
2671 		if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type,
2672 					      hcon->dst_type))
2673 			return SMP_UNSPECIFIED;
2674 		SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2675 		set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2676 		return 0;
2677 	}
2678 
2679 	/* The Initiating device waits for the non-initiating device to
2680 	 * send the confirm value.
2681 	 */
2682 	if (conn->hcon->out)
2683 		return 0;
2684 
2685 	err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd,
2686 		     0, cfm.confirm_val);
2687 	if (err)
2688 		return SMP_UNSPECIFIED;
2689 
2690 	smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
2691 	SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2692 
2693 	return 0;
2694 }
2695 
2696 static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb)
2697 {
2698 	struct smp_cmd_dhkey_check *check = (void *) skb->data;
2699 	struct l2cap_chan *chan = conn->smp;
2700 	struct hci_conn *hcon = conn->hcon;
2701 	struct smp_chan *smp = chan->data;
2702 	u8 a[7], b[7], *local_addr, *remote_addr;
2703 	u8 io_cap[3], r[16], e[16];
2704 	int err;
2705 
2706 	BT_DBG("conn %p", conn);
2707 
2708 	if (skb->len < sizeof(*check))
2709 		return SMP_INVALID_PARAMS;
2710 
2711 	memcpy(a, &hcon->init_addr, 6);
2712 	memcpy(b, &hcon->resp_addr, 6);
2713 	a[6] = hcon->init_addr_type;
2714 	b[6] = hcon->resp_addr_type;
2715 
2716 	if (hcon->out) {
2717 		local_addr = a;
2718 		remote_addr = b;
2719 		memcpy(io_cap, &smp->prsp[1], 3);
2720 	} else {
2721 		local_addr = b;
2722 		remote_addr = a;
2723 		memcpy(io_cap, &smp->preq[1], 3);
2724 	}
2725 
2726 	memset(r, 0, sizeof(r));
2727 
2728 	if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2729 		put_unaligned_le32(hcon->passkey_notify, r);
2730 	else if (smp->method == REQ_OOB)
2731 		memcpy(r, smp->lr, 16);
2732 
2733 	err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r,
2734 		     io_cap, remote_addr, local_addr, e);
2735 	if (err)
2736 		return SMP_UNSPECIFIED;
2737 
2738 	if (memcmp(check->e, e, 16))
2739 		return SMP_DHKEY_CHECK_FAILED;
2740 
2741 	if (!hcon->out) {
2742 		if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
2743 			set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags);
2744 			return 0;
2745 		}
2746 
2747 		/* Slave sends DHKey check as response to master */
2748 		sc_dhkey_check(smp);
2749 	}
2750 
2751 	sc_add_ltk(smp);
2752 
2753 	if (hcon->out) {
2754 		hci_le_start_enc(hcon, 0, 0, smp->tk, smp->enc_key_size);
2755 		hcon->enc_key_size = smp->enc_key_size;
2756 	}
2757 
2758 	return 0;
2759 }
2760 
2761 static int smp_cmd_keypress_notify(struct l2cap_conn *conn,
2762 				   struct sk_buff *skb)
2763 {
2764 	struct smp_cmd_keypress_notify *kp = (void *) skb->data;
2765 
2766 	BT_DBG("value 0x%02x", kp->value);
2767 
2768 	return 0;
2769 }
2770 
2771 static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb)
2772 {
2773 	struct l2cap_conn *conn = chan->conn;
2774 	struct hci_conn *hcon = conn->hcon;
2775 	struct smp_chan *smp;
2776 	__u8 code, reason;
2777 	int err = 0;
2778 
2779 	if (skb->len < 1)
2780 		return -EILSEQ;
2781 
2782 	if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) {
2783 		reason = SMP_PAIRING_NOTSUPP;
2784 		goto done;
2785 	}
2786 
2787 	code = skb->data[0];
2788 	skb_pull(skb, sizeof(code));
2789 
2790 	smp = chan->data;
2791 
2792 	if (code > SMP_CMD_MAX)
2793 		goto drop;
2794 
2795 	if (smp && !test_and_clear_bit(code, &smp->allow_cmd))
2796 		goto drop;
2797 
2798 	/* If we don't have a context the only allowed commands are
2799 	 * pairing request and security request.
2800 	 */
2801 	if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ)
2802 		goto drop;
2803 
2804 	switch (code) {
2805 	case SMP_CMD_PAIRING_REQ:
2806 		reason = smp_cmd_pairing_req(conn, skb);
2807 		break;
2808 
2809 	case SMP_CMD_PAIRING_FAIL:
2810 		smp_failure(conn, 0);
2811 		err = -EPERM;
2812 		break;
2813 
2814 	case SMP_CMD_PAIRING_RSP:
2815 		reason = smp_cmd_pairing_rsp(conn, skb);
2816 		break;
2817 
2818 	case SMP_CMD_SECURITY_REQ:
2819 		reason = smp_cmd_security_req(conn, skb);
2820 		break;
2821 
2822 	case SMP_CMD_PAIRING_CONFIRM:
2823 		reason = smp_cmd_pairing_confirm(conn, skb);
2824 		break;
2825 
2826 	case SMP_CMD_PAIRING_RANDOM:
2827 		reason = smp_cmd_pairing_random(conn, skb);
2828 		break;
2829 
2830 	case SMP_CMD_ENCRYPT_INFO:
2831 		reason = smp_cmd_encrypt_info(conn, skb);
2832 		break;
2833 
2834 	case SMP_CMD_MASTER_IDENT:
2835 		reason = smp_cmd_master_ident(conn, skb);
2836 		break;
2837 
2838 	case SMP_CMD_IDENT_INFO:
2839 		reason = smp_cmd_ident_info(conn, skb);
2840 		break;
2841 
2842 	case SMP_CMD_IDENT_ADDR_INFO:
2843 		reason = smp_cmd_ident_addr_info(conn, skb);
2844 		break;
2845 
2846 	case SMP_CMD_SIGN_INFO:
2847 		reason = smp_cmd_sign_info(conn, skb);
2848 		break;
2849 
2850 	case SMP_CMD_PUBLIC_KEY:
2851 		reason = smp_cmd_public_key(conn, skb);
2852 		break;
2853 
2854 	case SMP_CMD_DHKEY_CHECK:
2855 		reason = smp_cmd_dhkey_check(conn, skb);
2856 		break;
2857 
2858 	case SMP_CMD_KEYPRESS_NOTIFY:
2859 		reason = smp_cmd_keypress_notify(conn, skb);
2860 		break;
2861 
2862 	default:
2863 		BT_DBG("Unknown command code 0x%2.2x", code);
2864 		reason = SMP_CMD_NOTSUPP;
2865 		goto done;
2866 	}
2867 
2868 done:
2869 	if (!err) {
2870 		if (reason)
2871 			smp_failure(conn, reason);
2872 		kfree_skb(skb);
2873 	}
2874 
2875 	return err;
2876 
2877 drop:
2878 	BT_ERR("%s unexpected SMP command 0x%02x from %pMR", hcon->hdev->name,
2879 	       code, &hcon->dst);
2880 	kfree_skb(skb);
2881 	return 0;
2882 }
2883 
2884 static void smp_teardown_cb(struct l2cap_chan *chan, int err)
2885 {
2886 	struct l2cap_conn *conn = chan->conn;
2887 
2888 	BT_DBG("chan %p", chan);
2889 
2890 	if (chan->data)
2891 		smp_chan_destroy(conn);
2892 
2893 	conn->smp = NULL;
2894 	l2cap_chan_put(chan);
2895 }
2896 
2897 static void bredr_pairing(struct l2cap_chan *chan)
2898 {
2899 	struct l2cap_conn *conn = chan->conn;
2900 	struct hci_conn *hcon = conn->hcon;
2901 	struct hci_dev *hdev = hcon->hdev;
2902 	struct smp_cmd_pairing req;
2903 	struct smp_chan *smp;
2904 
2905 	BT_DBG("chan %p", chan);
2906 
2907 	/* Only new pairings are interesting */
2908 	if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags))
2909 		return;
2910 
2911 	/* Don't bother if we're not encrypted */
2912 	if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
2913 		return;
2914 
2915 	/* Only master may initiate SMP over BR/EDR */
2916 	if (hcon->role != HCI_ROLE_MASTER)
2917 		return;
2918 
2919 	/* Secure Connections support must be enabled */
2920 	if (!hci_dev_test_flag(hdev, HCI_SC_ENABLED))
2921 		return;
2922 
2923 	/* BR/EDR must use Secure Connections for SMP */
2924 	if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) &&
2925 	    !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
2926 		return;
2927 
2928 	/* If our LE support is not enabled don't do anything */
2929 	if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED))
2930 		return;
2931 
2932 	/* Don't bother if remote LE support is not enabled */
2933 	if (!lmp_host_le_capable(hcon))
2934 		return;
2935 
2936 	/* Remote must support SMP fixed chan for BR/EDR */
2937 	if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR))
2938 		return;
2939 
2940 	/* Don't bother if SMP is already ongoing */
2941 	if (chan->data)
2942 		return;
2943 
2944 	smp = smp_chan_create(conn);
2945 	if (!smp) {
2946 		BT_ERR("%s unable to create SMP context for BR/EDR",
2947 		       hdev->name);
2948 		return;
2949 	}
2950 
2951 	set_bit(SMP_FLAG_SC, &smp->flags);
2952 
2953 	BT_DBG("%s starting SMP over BR/EDR", hdev->name);
2954 
2955 	/* Prepare and send the BR/EDR SMP Pairing Request */
2956 	build_bredr_pairing_cmd(smp, &req, NULL);
2957 
2958 	smp->preq[0] = SMP_CMD_PAIRING_REQ;
2959 	memcpy(&smp->preq[1], &req, sizeof(req));
2960 
2961 	smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req);
2962 	SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2963 }
2964 
2965 static void smp_resume_cb(struct l2cap_chan *chan)
2966 {
2967 	struct smp_chan *smp = chan->data;
2968 	struct l2cap_conn *conn = chan->conn;
2969 	struct hci_conn *hcon = conn->hcon;
2970 
2971 	BT_DBG("chan %p", chan);
2972 
2973 	if (hcon->type == ACL_LINK) {
2974 		bredr_pairing(chan);
2975 		return;
2976 	}
2977 
2978 	if (!smp)
2979 		return;
2980 
2981 	if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
2982 		return;
2983 
2984 	cancel_delayed_work(&smp->security_timer);
2985 
2986 	smp_distribute_keys(smp);
2987 }
2988 
2989 static void smp_ready_cb(struct l2cap_chan *chan)
2990 {
2991 	struct l2cap_conn *conn = chan->conn;
2992 	struct hci_conn *hcon = conn->hcon;
2993 
2994 	BT_DBG("chan %p", chan);
2995 
2996 	/* No need to call l2cap_chan_hold() here since we already own
2997 	 * the reference taken in smp_new_conn_cb(). This is just the
2998 	 * first time that we tie it to a specific pointer. The code in
2999 	 * l2cap_core.c ensures that there's no risk this function wont
3000 	 * get called if smp_new_conn_cb was previously called.
3001 	 */
3002 	conn->smp = chan;
3003 
3004 	if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
3005 		bredr_pairing(chan);
3006 }
3007 
3008 static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
3009 {
3010 	int err;
3011 
3012 	BT_DBG("chan %p", chan);
3013 
3014 	err = smp_sig_channel(chan, skb);
3015 	if (err) {
3016 		struct smp_chan *smp = chan->data;
3017 
3018 		if (smp)
3019 			cancel_delayed_work_sync(&smp->security_timer);
3020 
3021 		hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE);
3022 	}
3023 
3024 	return err;
3025 }
3026 
3027 static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan,
3028 					unsigned long hdr_len,
3029 					unsigned long len, int nb)
3030 {
3031 	struct sk_buff *skb;
3032 
3033 	skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL);
3034 	if (!skb)
3035 		return ERR_PTR(-ENOMEM);
3036 
3037 	skb->priority = HCI_PRIO_MAX;
3038 	bt_cb(skb)->l2cap.chan = chan;
3039 
3040 	return skb;
3041 }
3042 
3043 static const struct l2cap_ops smp_chan_ops = {
3044 	.name			= "Security Manager",
3045 	.ready			= smp_ready_cb,
3046 	.recv			= smp_recv_cb,
3047 	.alloc_skb		= smp_alloc_skb_cb,
3048 	.teardown		= smp_teardown_cb,
3049 	.resume			= smp_resume_cb,
3050 
3051 	.new_connection		= l2cap_chan_no_new_connection,
3052 	.state_change		= l2cap_chan_no_state_change,
3053 	.close			= l2cap_chan_no_close,
3054 	.defer			= l2cap_chan_no_defer,
3055 	.suspend		= l2cap_chan_no_suspend,
3056 	.set_shutdown		= l2cap_chan_no_set_shutdown,
3057 	.get_sndtimeo		= l2cap_chan_no_get_sndtimeo,
3058 };
3059 
3060 static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan)
3061 {
3062 	struct l2cap_chan *chan;
3063 
3064 	BT_DBG("pchan %p", pchan);
3065 
3066 	chan = l2cap_chan_create();
3067 	if (!chan)
3068 		return NULL;
3069 
3070 	chan->chan_type	= pchan->chan_type;
3071 	chan->ops	= &smp_chan_ops;
3072 	chan->scid	= pchan->scid;
3073 	chan->dcid	= chan->scid;
3074 	chan->imtu	= pchan->imtu;
3075 	chan->omtu	= pchan->omtu;
3076 	chan->mode	= pchan->mode;
3077 
3078 	/* Other L2CAP channels may request SMP routines in order to
3079 	 * change the security level. This means that the SMP channel
3080 	 * lock must be considered in its own category to avoid lockdep
3081 	 * warnings.
3082 	 */
3083 	atomic_set(&chan->nesting, L2CAP_NESTING_SMP);
3084 
3085 	BT_DBG("created chan %p", chan);
3086 
3087 	return chan;
3088 }
3089 
3090 static const struct l2cap_ops smp_root_chan_ops = {
3091 	.name			= "Security Manager Root",
3092 	.new_connection		= smp_new_conn_cb,
3093 
3094 	/* None of these are implemented for the root channel */
3095 	.close			= l2cap_chan_no_close,
3096 	.alloc_skb		= l2cap_chan_no_alloc_skb,
3097 	.recv			= l2cap_chan_no_recv,
3098 	.state_change		= l2cap_chan_no_state_change,
3099 	.teardown		= l2cap_chan_no_teardown,
3100 	.ready			= l2cap_chan_no_ready,
3101 	.defer			= l2cap_chan_no_defer,
3102 	.suspend		= l2cap_chan_no_suspend,
3103 	.resume			= l2cap_chan_no_resume,
3104 	.set_shutdown		= l2cap_chan_no_set_shutdown,
3105 	.get_sndtimeo		= l2cap_chan_no_get_sndtimeo,
3106 };
3107 
3108 static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid)
3109 {
3110 	struct l2cap_chan *chan;
3111 	struct smp_dev *smp;
3112 	struct crypto_cipher *tfm_aes;
3113 	struct crypto_shash *tfm_cmac;
3114 
3115 	if (cid == L2CAP_CID_SMP_BREDR) {
3116 		smp = NULL;
3117 		goto create_chan;
3118 	}
3119 
3120 	smp = kzalloc(sizeof(*smp), GFP_KERNEL);
3121 	if (!smp)
3122 		return ERR_PTR(-ENOMEM);
3123 
3124 	tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
3125 	if (IS_ERR(tfm_aes)) {
3126 		BT_ERR("Unable to create AES crypto context");
3127 		kzfree(smp);
3128 		return ERR_CAST(tfm_aes);
3129 	}
3130 
3131 	tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
3132 	if (IS_ERR(tfm_cmac)) {
3133 		BT_ERR("Unable to create CMAC crypto context");
3134 		crypto_free_cipher(tfm_aes);
3135 		kzfree(smp);
3136 		return ERR_CAST(tfm_cmac);
3137 	}
3138 
3139 	smp->tfm_aes = tfm_aes;
3140 	smp->tfm_cmac = tfm_cmac;
3141 	smp->min_key_size = SMP_MIN_ENC_KEY_SIZE;
3142 	smp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
3143 
3144 create_chan:
3145 	chan = l2cap_chan_create();
3146 	if (!chan) {
3147 		if (smp) {
3148 			crypto_free_cipher(smp->tfm_aes);
3149 			crypto_free_shash(smp->tfm_cmac);
3150 			kzfree(smp);
3151 		}
3152 		return ERR_PTR(-ENOMEM);
3153 	}
3154 
3155 	chan->data = smp;
3156 
3157 	l2cap_add_scid(chan, cid);
3158 
3159 	l2cap_chan_set_defaults(chan);
3160 
3161 	if (cid == L2CAP_CID_SMP) {
3162 		u8 bdaddr_type;
3163 
3164 		hci_copy_identity_address(hdev, &chan->src, &bdaddr_type);
3165 
3166 		if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
3167 			chan->src_type = BDADDR_LE_PUBLIC;
3168 		else
3169 			chan->src_type = BDADDR_LE_RANDOM;
3170 	} else {
3171 		bacpy(&chan->src, &hdev->bdaddr);
3172 		chan->src_type = BDADDR_BREDR;
3173 	}
3174 
3175 	chan->state = BT_LISTEN;
3176 	chan->mode = L2CAP_MODE_BASIC;
3177 	chan->imtu = L2CAP_DEFAULT_MTU;
3178 	chan->ops = &smp_root_chan_ops;
3179 
3180 	/* Set correct nesting level for a parent/listening channel */
3181 	atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
3182 
3183 	return chan;
3184 }
3185 
3186 static void smp_del_chan(struct l2cap_chan *chan)
3187 {
3188 	struct smp_dev *smp;
3189 
3190 	BT_DBG("chan %p", chan);
3191 
3192 	smp = chan->data;
3193 	if (smp) {
3194 		chan->data = NULL;
3195 		crypto_free_cipher(smp->tfm_aes);
3196 		crypto_free_shash(smp->tfm_cmac);
3197 		kzfree(smp);
3198 	}
3199 
3200 	l2cap_chan_put(chan);
3201 }
3202 
3203 static ssize_t force_bredr_smp_read(struct file *file,
3204 				    char __user *user_buf,
3205 				    size_t count, loff_t *ppos)
3206 {
3207 	struct hci_dev *hdev = file->private_data;
3208 	char buf[3];
3209 
3210 	buf[0] = hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP) ? 'Y': 'N';
3211 	buf[1] = '\n';
3212 	buf[2] = '\0';
3213 	return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
3214 }
3215 
3216 static ssize_t force_bredr_smp_write(struct file *file,
3217 				     const char __user *user_buf,
3218 				     size_t count, loff_t *ppos)
3219 {
3220 	struct hci_dev *hdev = file->private_data;
3221 	char buf[32];
3222 	size_t buf_size = min(count, (sizeof(buf)-1));
3223 	bool enable;
3224 
3225 	if (copy_from_user(buf, user_buf, buf_size))
3226 		return -EFAULT;
3227 
3228 	buf[buf_size] = '\0';
3229 	if (strtobool(buf, &enable))
3230 		return -EINVAL;
3231 
3232 	if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3233 		return -EALREADY;
3234 
3235 	if (enable) {
3236 		struct l2cap_chan *chan;
3237 
3238 		chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3239 		if (IS_ERR(chan))
3240 			return PTR_ERR(chan);
3241 
3242 		hdev->smp_bredr_data = chan;
3243 	} else {
3244 		struct l2cap_chan *chan;
3245 
3246 		chan = hdev->smp_bredr_data;
3247 		hdev->smp_bredr_data = NULL;
3248 		smp_del_chan(chan);
3249 	}
3250 
3251 	hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP);
3252 
3253 	return count;
3254 }
3255 
3256 static const struct file_operations force_bredr_smp_fops = {
3257 	.open		= simple_open,
3258 	.read		= force_bredr_smp_read,
3259 	.write		= force_bredr_smp_write,
3260 	.llseek		= default_llseek,
3261 };
3262 
3263 static ssize_t le_min_key_size_read(struct file *file,
3264 				     char __user *user_buf,
3265 				     size_t count, loff_t *ppos)
3266 {
3267 	struct hci_dev *hdev = file->private_data;
3268 	char buf[4];
3269 
3270 	snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->min_key_size);
3271 
3272 	return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf));
3273 }
3274 
3275 static ssize_t le_min_key_size_write(struct file *file,
3276 				      const char __user *user_buf,
3277 				      size_t count, loff_t *ppos)
3278 {
3279 	struct hci_dev *hdev = file->private_data;
3280 	char buf[32];
3281 	size_t buf_size = min(count, (sizeof(buf) - 1));
3282 	u8 key_size;
3283 
3284 	if (copy_from_user(buf, user_buf, buf_size))
3285 		return -EFAULT;
3286 
3287 	buf[buf_size] = '\0';
3288 
3289 	sscanf(buf, "%hhu", &key_size);
3290 
3291 	if (key_size > SMP_DEV(hdev)->max_key_size ||
3292 	    key_size < SMP_MIN_ENC_KEY_SIZE)
3293 		return -EINVAL;
3294 
3295 	SMP_DEV(hdev)->min_key_size = key_size;
3296 
3297 	return count;
3298 }
3299 
3300 static const struct file_operations le_min_key_size_fops = {
3301 	.open		= simple_open,
3302 	.read		= le_min_key_size_read,
3303 	.write		= le_min_key_size_write,
3304 	.llseek		= default_llseek,
3305 };
3306 
3307 static ssize_t le_max_key_size_read(struct file *file,
3308 				     char __user *user_buf,
3309 				     size_t count, loff_t *ppos)
3310 {
3311 	struct hci_dev *hdev = file->private_data;
3312 	char buf[4];
3313 
3314 	snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->max_key_size);
3315 
3316 	return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf));
3317 }
3318 
3319 static ssize_t le_max_key_size_write(struct file *file,
3320 				      const char __user *user_buf,
3321 				      size_t count, loff_t *ppos)
3322 {
3323 	struct hci_dev *hdev = file->private_data;
3324 	char buf[32];
3325 	size_t buf_size = min(count, (sizeof(buf) - 1));
3326 	u8 key_size;
3327 
3328 	if (copy_from_user(buf, user_buf, buf_size))
3329 		return -EFAULT;
3330 
3331 	buf[buf_size] = '\0';
3332 
3333 	sscanf(buf, "%hhu", &key_size);
3334 
3335 	if (key_size > SMP_MAX_ENC_KEY_SIZE ||
3336 	    key_size < SMP_DEV(hdev)->min_key_size)
3337 		return -EINVAL;
3338 
3339 	SMP_DEV(hdev)->max_key_size = key_size;
3340 
3341 	return count;
3342 }
3343 
3344 static const struct file_operations le_max_key_size_fops = {
3345 	.open		= simple_open,
3346 	.read		= le_max_key_size_read,
3347 	.write		= le_max_key_size_write,
3348 	.llseek		= default_llseek,
3349 };
3350 
3351 int smp_register(struct hci_dev *hdev)
3352 {
3353 	struct l2cap_chan *chan;
3354 
3355 	BT_DBG("%s", hdev->name);
3356 
3357 	/* If the controller does not support Low Energy operation, then
3358 	 * there is also no need to register any SMP channel.
3359 	 */
3360 	if (!lmp_le_capable(hdev))
3361 		return 0;
3362 
3363 	if (WARN_ON(hdev->smp_data)) {
3364 		chan = hdev->smp_data;
3365 		hdev->smp_data = NULL;
3366 		smp_del_chan(chan);
3367 	}
3368 
3369 	chan = smp_add_cid(hdev, L2CAP_CID_SMP);
3370 	if (IS_ERR(chan))
3371 		return PTR_ERR(chan);
3372 
3373 	hdev->smp_data = chan;
3374 
3375 	debugfs_create_file("le_min_key_size", 0644, hdev->debugfs, hdev,
3376 			    &le_min_key_size_fops);
3377 	debugfs_create_file("le_max_key_size", 0644, hdev->debugfs, hdev,
3378 			    &le_max_key_size_fops);
3379 
3380 	/* If the controller does not support BR/EDR Secure Connections
3381 	 * feature, then the BR/EDR SMP channel shall not be present.
3382 	 *
3383 	 * To test this with Bluetooth 4.0 controllers, create a debugfs
3384 	 * switch that allows forcing BR/EDR SMP support and accepting
3385 	 * cross-transport pairing on non-AES encrypted connections.
3386 	 */
3387 	if (!lmp_sc_capable(hdev)) {
3388 		debugfs_create_file("force_bredr_smp", 0644, hdev->debugfs,
3389 				    hdev, &force_bredr_smp_fops);
3390 		return 0;
3391 	}
3392 
3393 	if (WARN_ON(hdev->smp_bredr_data)) {
3394 		chan = hdev->smp_bredr_data;
3395 		hdev->smp_bredr_data = NULL;
3396 		smp_del_chan(chan);
3397 	}
3398 
3399 	chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3400 	if (IS_ERR(chan)) {
3401 		int err = PTR_ERR(chan);
3402 		chan = hdev->smp_data;
3403 		hdev->smp_data = NULL;
3404 		smp_del_chan(chan);
3405 		return err;
3406 	}
3407 
3408 	hdev->smp_bredr_data = chan;
3409 
3410 	return 0;
3411 }
3412 
3413 void smp_unregister(struct hci_dev *hdev)
3414 {
3415 	struct l2cap_chan *chan;
3416 
3417 	if (hdev->smp_bredr_data) {
3418 		chan = hdev->smp_bredr_data;
3419 		hdev->smp_bredr_data = NULL;
3420 		smp_del_chan(chan);
3421 	}
3422 
3423 	if (hdev->smp_data) {
3424 		chan = hdev->smp_data;
3425 		hdev->smp_data = NULL;
3426 		smp_del_chan(chan);
3427 	}
3428 }
3429 
3430 #if IS_ENABLED(CONFIG_BT_SELFTEST_SMP)
3431 
3432 static int __init test_ah(struct crypto_cipher *tfm_aes)
3433 {
3434 	const u8 irk[16] = {
3435 			0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3436 			0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3437 	const u8 r[3] = { 0x94, 0x81, 0x70 };
3438 	const u8 exp[3] = { 0xaa, 0xfb, 0x0d };
3439 	u8 res[3];
3440 	int err;
3441 
3442 	err = smp_ah(tfm_aes, irk, r, res);
3443 	if (err)
3444 		return err;
3445 
3446 	if (memcmp(res, exp, 3))
3447 		return -EINVAL;
3448 
3449 	return 0;
3450 }
3451 
3452 static int __init test_c1(struct crypto_cipher *tfm_aes)
3453 {
3454 	const u8 k[16] = {
3455 			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
3456 			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
3457 	const u8 r[16] = {
3458 			0xe0, 0x2e, 0x70, 0xc6, 0x4e, 0x27, 0x88, 0x63,
3459 			0x0e, 0x6f, 0xad, 0x56, 0x21, 0xd5, 0x83, 0x57 };
3460 	const u8 preq[7] = { 0x01, 0x01, 0x00, 0x00, 0x10, 0x07, 0x07 };
3461 	const u8 pres[7] = { 0x02, 0x03, 0x00, 0x00, 0x08, 0x00, 0x05 };
3462 	const u8 _iat = 0x01;
3463 	const u8 _rat = 0x00;
3464 	const bdaddr_t ra = { { 0xb6, 0xb5, 0xb4, 0xb3, 0xb2, 0xb1 } };
3465 	const bdaddr_t ia = { { 0xa6, 0xa5, 0xa4, 0xa3, 0xa2, 0xa1 } };
3466 	const u8 exp[16] = {
3467 			0x86, 0x3b, 0xf1, 0xbe, 0xc5, 0x4d, 0xa7, 0xd2,
3468 			0xea, 0x88, 0x89, 0x87, 0xef, 0x3f, 0x1e, 0x1e };
3469 	u8 res[16];
3470 	int err;
3471 
3472 	err = smp_c1(tfm_aes, k, r, preq, pres, _iat, &ia, _rat, &ra, res);
3473 	if (err)
3474 		return err;
3475 
3476 	if (memcmp(res, exp, 16))
3477 		return -EINVAL;
3478 
3479 	return 0;
3480 }
3481 
3482 static int __init test_s1(struct crypto_cipher *tfm_aes)
3483 {
3484 	const u8 k[16] = {
3485 			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
3486 			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
3487 	const u8 r1[16] = {
3488 			0x88, 0x77, 0x66, 0x55, 0x44, 0x33, 0x22, 0x11 };
3489 	const u8 r2[16] = {
3490 			0x00, 0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa, 0x99 };
3491 	const u8 exp[16] = {
3492 			0x62, 0xa0, 0x6d, 0x79, 0xae, 0x16, 0x42, 0x5b,
3493 			0x9b, 0xf4, 0xb0, 0xe8, 0xf0, 0xe1, 0x1f, 0x9a };
3494 	u8 res[16];
3495 	int err;
3496 
3497 	err = smp_s1(tfm_aes, k, r1, r2, res);
3498 	if (err)
3499 		return err;
3500 
3501 	if (memcmp(res, exp, 16))
3502 		return -EINVAL;
3503 
3504 	return 0;
3505 }
3506 
3507 static int __init test_f4(struct crypto_shash *tfm_cmac)
3508 {
3509 	const u8 u[32] = {
3510 			0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
3511 			0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
3512 			0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
3513 			0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 };
3514 	const u8 v[32] = {
3515 			0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b,
3516 			0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59,
3517 			0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90,
3518 			0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 };
3519 	const u8 x[16] = {
3520 			0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3521 			0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3522 	const u8 z = 0x00;
3523 	const u8 exp[16] = {
3524 			0x2d, 0x87, 0x74, 0xa9, 0xbe, 0xa1, 0xed, 0xf1,
3525 			0x1c, 0xbd, 0xa9, 0x07, 0xf1, 0x16, 0xc9, 0xf2 };
3526 	u8 res[16];
3527 	int err;
3528 
3529 	err = smp_f4(tfm_cmac, u, v, x, z, res);
3530 	if (err)
3531 		return err;
3532 
3533 	if (memcmp(res, exp, 16))
3534 		return -EINVAL;
3535 
3536 	return 0;
3537 }
3538 
3539 static int __init test_f5(struct crypto_shash *tfm_cmac)
3540 {
3541 	const u8 w[32] = {
3542 			0x98, 0xa6, 0xbf, 0x73, 0xf3, 0x34, 0x8d, 0x86,
3543 			0xf1, 0x66, 0xf8, 0xb4, 0x13, 0x6b, 0x79, 0x99,
3544 			0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3545 			0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3546 	const u8 n1[16] = {
3547 			0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3548 			0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3549 	const u8 n2[16] = {
3550 			0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3551 			0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3552 	const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 };
3553 	const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 };
3554 	const u8 exp_ltk[16] = {
3555 			0x38, 0x0a, 0x75, 0x94, 0xb5, 0x22, 0x05, 0x98,
3556 			0x23, 0xcd, 0xd7, 0x69, 0x11, 0x79, 0x86, 0x69 };
3557 	const u8 exp_mackey[16] = {
3558 			0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd,
3559 			0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 };
3560 	u8 mackey[16], ltk[16];
3561 	int err;
3562 
3563 	err = smp_f5(tfm_cmac, w, n1, n2, a1, a2, mackey, ltk);
3564 	if (err)
3565 		return err;
3566 
3567 	if (memcmp(mackey, exp_mackey, 16))
3568 		return -EINVAL;
3569 
3570 	if (memcmp(ltk, exp_ltk, 16))
3571 		return -EINVAL;
3572 
3573 	return 0;
3574 }
3575 
3576 static int __init test_f6(struct crypto_shash *tfm_cmac)
3577 {
3578 	const u8 w[16] = {
3579 			0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd,
3580 			0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 };
3581 	const u8 n1[16] = {
3582 			0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3583 			0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3584 	const u8 n2[16] = {
3585 			0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3586 			0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3587 	const u8 r[16] = {
3588 			0xc8, 0x0f, 0x2d, 0x0c, 0xd2, 0x42, 0xda, 0x08,
3589 			0x54, 0xbb, 0x53, 0xb4, 0x3b, 0x34, 0xa3, 0x12 };
3590 	const u8 io_cap[3] = { 0x02, 0x01, 0x01 };
3591 	const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 };
3592 	const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 };
3593 	const u8 exp[16] = {
3594 			0x61, 0x8f, 0x95, 0xda, 0x09, 0x0b, 0x6c, 0xd2,
3595 			0xc5, 0xe8, 0xd0, 0x9c, 0x98, 0x73, 0xc4, 0xe3 };
3596 	u8 res[16];
3597 	int err;
3598 
3599 	err = smp_f6(tfm_cmac, w, n1, n2, r, io_cap, a1, a2, res);
3600 	if (err)
3601 		return err;
3602 
3603 	if (memcmp(res, exp, 16))
3604 		return -EINVAL;
3605 
3606 	return 0;
3607 }
3608 
3609 static int __init test_g2(struct crypto_shash *tfm_cmac)
3610 {
3611 	const u8 u[32] = {
3612 			0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
3613 			0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
3614 			0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
3615 			0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 };
3616 	const u8 v[32] = {
3617 			0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b,
3618 			0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59,
3619 			0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90,
3620 			0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 };
3621 	const u8 x[16] = {
3622 			0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3623 			0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3624 	const u8 y[16] = {
3625 			0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3626 			0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3627 	const u32 exp_val = 0x2f9ed5ba % 1000000;
3628 	u32 val;
3629 	int err;
3630 
3631 	err = smp_g2(tfm_cmac, u, v, x, y, &val);
3632 	if (err)
3633 		return err;
3634 
3635 	if (val != exp_val)
3636 		return -EINVAL;
3637 
3638 	return 0;
3639 }
3640 
3641 static int __init test_h6(struct crypto_shash *tfm_cmac)
3642 {
3643 	const u8 w[16] = {
3644 			0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3645 			0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3646 	const u8 key_id[4] = { 0x72, 0x62, 0x65, 0x6c };
3647 	const u8 exp[16] = {
3648 			0x99, 0x63, 0xb1, 0x80, 0xe2, 0xa9, 0xd3, 0xe8,
3649 			0x1c, 0xc9, 0x6d, 0xe7, 0x02, 0xe1, 0x9a, 0x2d };
3650 	u8 res[16];
3651 	int err;
3652 
3653 	err = smp_h6(tfm_cmac, w, key_id, res);
3654 	if (err)
3655 		return err;
3656 
3657 	if (memcmp(res, exp, 16))
3658 		return -EINVAL;
3659 
3660 	return 0;
3661 }
3662 
3663 static char test_smp_buffer[32];
3664 
3665 static ssize_t test_smp_read(struct file *file, char __user *user_buf,
3666 			     size_t count, loff_t *ppos)
3667 {
3668 	return simple_read_from_buffer(user_buf, count, ppos, test_smp_buffer,
3669 				       strlen(test_smp_buffer));
3670 }
3671 
3672 static const struct file_operations test_smp_fops = {
3673 	.open		= simple_open,
3674 	.read		= test_smp_read,
3675 	.llseek		= default_llseek,
3676 };
3677 
3678 static int __init run_selftests(struct crypto_cipher *tfm_aes,
3679 				struct crypto_shash *tfm_cmac)
3680 {
3681 	ktime_t calltime, delta, rettime;
3682 	unsigned long long duration;
3683 	int err;
3684 
3685 	calltime = ktime_get();
3686 
3687 	err = test_ah(tfm_aes);
3688 	if (err) {
3689 		BT_ERR("smp_ah test failed");
3690 		goto done;
3691 	}
3692 
3693 	err = test_c1(tfm_aes);
3694 	if (err) {
3695 		BT_ERR("smp_c1 test failed");
3696 		goto done;
3697 	}
3698 
3699 	err = test_s1(tfm_aes);
3700 	if (err) {
3701 		BT_ERR("smp_s1 test failed");
3702 		goto done;
3703 	}
3704 
3705 	err = test_f4(tfm_cmac);
3706 	if (err) {
3707 		BT_ERR("smp_f4 test failed");
3708 		goto done;
3709 	}
3710 
3711 	err = test_f5(tfm_cmac);
3712 	if (err) {
3713 		BT_ERR("smp_f5 test failed");
3714 		goto done;
3715 	}
3716 
3717 	err = test_f6(tfm_cmac);
3718 	if (err) {
3719 		BT_ERR("smp_f6 test failed");
3720 		goto done;
3721 	}
3722 
3723 	err = test_g2(tfm_cmac);
3724 	if (err) {
3725 		BT_ERR("smp_g2 test failed");
3726 		goto done;
3727 	}
3728 
3729 	err = test_h6(tfm_cmac);
3730 	if (err) {
3731 		BT_ERR("smp_h6 test failed");
3732 		goto done;
3733 	}
3734 
3735 	rettime = ktime_get();
3736 	delta = ktime_sub(rettime, calltime);
3737 	duration = (unsigned long long) ktime_to_ns(delta) >> 10;
3738 
3739 	BT_INFO("SMP test passed in %llu usecs", duration);
3740 
3741 done:
3742 	if (!err)
3743 		snprintf(test_smp_buffer, sizeof(test_smp_buffer),
3744 			 "PASS (%llu usecs)\n", duration);
3745 	else
3746 		snprintf(test_smp_buffer, sizeof(test_smp_buffer), "FAIL\n");
3747 
3748 	debugfs_create_file("selftest_smp", 0444, bt_debugfs, NULL,
3749 			    &test_smp_fops);
3750 
3751 	return err;
3752 }
3753 
3754 int __init bt_selftest_smp(void)
3755 {
3756 	struct crypto_cipher *tfm_aes;
3757 	struct crypto_shash *tfm_cmac;
3758 	int err;
3759 
3760 	tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
3761 	if (IS_ERR(tfm_aes)) {
3762 		BT_ERR("Unable to create AES crypto context");
3763 		return PTR_ERR(tfm_aes);
3764 	}
3765 
3766 	tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, CRYPTO_ALG_ASYNC);
3767 	if (IS_ERR(tfm_cmac)) {
3768 		BT_ERR("Unable to create CMAC crypto context");
3769 		crypto_free_cipher(tfm_aes);
3770 		return PTR_ERR(tfm_cmac);
3771 	}
3772 
3773 	err = run_selftests(tfm_aes, tfm_cmac);
3774 
3775 	crypto_free_shash(tfm_cmac);
3776 	crypto_free_cipher(tfm_aes);
3777 
3778 	return err;
3779 }
3780 
3781 #endif
3782