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cc2520: fix zero perm_extended_addr address
[deliverable/linux.git] / net / bluetooth / smp.c
CommitLineData
eb492e01
AB		 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
8c520a59
GP		 23#include <linux/crypto.h>
24#include <linux/scatterlist.h>
25#include <crypto/b128ops.h>
26
eb492e01
AB		 27#include <net/bluetooth/bluetooth.h>
28#include <net/bluetooth/hci_core.h>
29#include <net/bluetooth/l2cap.h>
2b64d153 30#include <net/bluetooth/mgmt.h>
ac4b7236 31
3b19146d 32#include "ecc.h"
ac4b7236 33#include "smp.h"
d22ef0bc 34
c7a3d57d
JH		 35/* Low-level debug macros to be used for stuff that we don't want
36 * accidentially in dmesg, i.e. the values of the various crypto keys
37 * and the inputs & outputs of crypto functions.
38 */
39#ifdef DEBUG
40#define SMP_DBG(fmt, ...) printk(KERN_DEBUG "%s: " fmt, __func__, \
41 ##__VA_ARGS__)
42#else
43#define SMP_DBG(fmt, ...) no_printk(KERN_DEBUG "%s: " fmt, __func__, \
44 ##__VA_ARGS__)
45#endif
46
b28b4943 47#define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd)
b28b4943 48
3b19146d
JH		 49/* Keys which are not distributed with Secure Connections */
50#define SMP_SC_NO_DIST (SMP_DIST_ENC_KEY | SMP_DIST_LINK_KEY);
51
17b02e62 52#define SMP_TIMEOUT msecs_to_jiffies(30000)
5d3de7df 53
0edb14de
JH		 54#define AUTH_REQ_MASK(dev) (test_bit(HCI_SC_ENABLED, &(dev)->dev_flags) ? \
55 0x1f : 0x07)
56#define KEY_DIST_MASK 0x07
065a13e2 57
cbbbe3e2
JH		 58/* Maximum message length that can be passed to aes_cmac */
59#define CMAC_MSG_MAX 80
60
533e35d4
JH		 61enum {
62 SMP_FLAG_TK_VALID,
63 SMP_FLAG_CFM_PENDING,
64 SMP_FLAG_MITM_AUTH,
65 SMP_FLAG_COMPLETE,
66 SMP_FLAG_INITIATOR,
65668776 67 SMP_FLAG_SC,
d8f8edbe 68 SMP_FLAG_REMOTE_PK,
aeb7d461 69 SMP_FLAG_DEBUG_KEY,
38606f14 70 SMP_FLAG_WAIT_USER,
d3e54a87 71 SMP_FLAG_DHKEY_PENDING,
02b05bd8 72 SMP_FLAG_OOB,
533e35d4 73};
4bc58f51
JH		 74
75struct smp_chan {
b68fda68
JH		 76 struct l2cap_conn *conn;
77 struct delayed_work security_timer;
b28b4943 78 unsigned long allow_cmd; /* Bitmask of allowed commands */
b68fda68 79
4bc58f51
JH		 80 u8 preq[7]; /* SMP Pairing Request */
81 u8 prsp[7]; /* SMP Pairing Response */
82 u8 prnd[16]; /* SMP Pairing Random (local) */
83 u8 rrnd[16]; /* SMP Pairing Random (remote) */
84 u8 pcnf[16]; /* SMP Pairing Confirm */
85 u8 tk[16]; /* SMP Temporary Key */
a29b0733 86 u8 rr[16];
4bc58f51
JH		 87 u8 enc_key_size;
88 u8 remote_key_dist;
89 bdaddr_t id_addr;
90 u8 id_addr_type;
91 u8 irk[16];
92 struct smp_csrk *csrk;
93 struct smp_csrk *slave_csrk;
94 struct smp_ltk *ltk;
95 struct smp_ltk *slave_ltk;
96 struct smp_irk *remote_irk;
6a77083a 97 u8 *link_key;
4a74d658 98 unsigned long flags;
783e0574 99 u8 method;
38606f14 100 u8 passkey_round;
6a7bd103 101
3b19146d
JH		 102 /* Secure Connections variables */
103 u8 local_pk[64];
104 u8 local_sk[32];
d8f8edbe
JH		 105 u8 remote_pk[64];
106 u8 dhkey[32];
760b018b 107 u8 mackey[16];
3b19146d 108
6a7bd103 109 struct crypto_blkcipher *tfm_aes;
407cecf6 110 struct crypto_hash *tfm_cmac;
4bc58f51
JH		 111};
112
aeb7d461
JH		 113/* These debug key values are defined in the SMP section of the core
114 * specification. debug_pk is the public debug key and debug_sk the
115 * private debug key.
116 */
117static const u8 debug_pk[64] = {
118 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
119 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
120 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
121 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20,
122
123 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74,
124 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76,
125 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63,
126 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc,
127};
128
129static const u8 debug_sk[32] = {
130 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58,
131 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a,
132 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74,
133 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f,
134};
135
8a2936f4 136static inline void swap_buf(const u8 *src, u8 *dst, size_t len)
d22ef0bc 137{
8a2936f4 138 size_t i;
d22ef0bc 139
8a2936f4
JH		 140 for (i = 0; i < len; i++)
141 dst[len - 1 - i] = src[i];
d22ef0bc
AB		 142}
143
06edf8de
JH		 144/* The following functions map to the LE SC SMP crypto functions
145 * AES-CMAC, f4, f5, f6, g2 and h6.
146 */
147
cbbbe3e2
JH		 148static int aes_cmac(struct crypto_hash *tfm, const u8 k[16], const u8 *m,
149 size_t len, u8 mac[16])
150{
151 uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX];
152 struct hash_desc desc;
153 struct scatterlist sg;
154 int err;
155
156 if (len > CMAC_MSG_MAX)
157 return -EFBIG;
158
159 if (!tfm) {
160 BT_ERR("tfm %p", tfm);
161 return -EINVAL;
162 }
163
164 desc.tfm = tfm;
165 desc.flags = 0;
166
167 crypto_hash_init(&desc);
168
169 /* Swap key and message from LSB to MSB */
170 swap_buf(k, tmp, 16);
171 swap_buf(m, msg_msb, len);
172
c7a3d57d
JH		 173 SMP_DBG("msg (len %zu) %*phN", len, (int) len, m);
174 SMP_DBG("key %16phN", k);
cbbbe3e2
JH		 175
176 err = crypto_hash_setkey(tfm, tmp, 16);
177 if (err) {
178 BT_ERR("cipher setkey failed: %d", err);
179 return err;
180 }
181
182 sg_init_one(&sg, msg_msb, len);
183
184 err = crypto_hash_update(&desc, &sg, len);
185 if (err) {
186 BT_ERR("Hash update error %d", err);
187 return err;
188 }
189
190 err = crypto_hash_final(&desc, mac_msb);
191 if (err) {
192 BT_ERR("Hash final error %d", err);
193 return err;
194 }
195
196 swap_buf(mac_msb, mac, 16);
197
c7a3d57d 198 SMP_DBG("mac %16phN", mac);
cbbbe3e2
JH		 199
200 return 0;
201}
202
203static int smp_f4(struct crypto_hash *tfm_cmac, const u8 u[32], const u8 v[32],
204 const u8 x[16], u8 z, u8 res[16])
205{
206 u8 m[65];
207 int err;
208
c7a3d57d
JH		 209 SMP_DBG("u %32phN", u);
210 SMP_DBG("v %32phN", v);
211 SMP_DBG("x %16phN z %02x", x, z);
cbbbe3e2
JH		 212
213 m[0] = z;
214 memcpy(m + 1, v, 32);
215 memcpy(m + 33, u, 32);
216
217 err = aes_cmac(tfm_cmac, x, m, sizeof(m), res);
218 if (err)
219 return err;
220
c7a3d57d 221 SMP_DBG("res %16phN", res);
cbbbe3e2
JH		 222
223 return err;
224}
225
760b018b
JH		 226static int smp_f5(struct crypto_hash *tfm_cmac, u8 w[32], u8 n1[16], u8 n2[16],
227 u8 a1[7], u8 a2[7], u8 mackey[16], u8 ltk[16])
228{
229 /* The btle, salt and length "magic" values are as defined in
230 * the SMP section of the Bluetooth core specification. In ASCII
231 * the btle value ends up being 'btle'. The salt is just a
232 * random number whereas length is the value 256 in little
233 * endian format.
234 */
235 const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 };
236 const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60,
237 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c };
238 const u8 length[2] = { 0x00, 0x01 };
239 u8 m[53], t[16];
240 int err;
241
c7a3d57d
JH		 242 SMP_DBG("w %32phN", w);
243 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
244 SMP_DBG("a1 %7phN a2 %7phN", a1, a2);
760b018b
JH		 245
246 err = aes_cmac(tfm_cmac, salt, w, 32, t);
247 if (err)
248 return err;
249
c7a3d57d 250 SMP_DBG("t %16phN", t);
760b018b
JH		 251
252 memcpy(m, length, 2);
253 memcpy(m + 2, a2, 7);
254 memcpy(m + 9, a1, 7);
255 memcpy(m + 16, n2, 16);
256 memcpy(m + 32, n1, 16);
257 memcpy(m + 48, btle, 4);
258
259 m[52] = 0; /* Counter */
260
261 err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey);
262 if (err)
263 return err;
264
c7a3d57d 265 SMP_DBG("mackey %16phN", mackey);
760b018b
JH		 266
267 m[52] = 1; /* Counter */
268
269 err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk);
270 if (err)
271 return err;
272
c7a3d57d 273 SMP_DBG("ltk %16phN", ltk);
760b018b
JH		 274
275 return 0;
276}
277
278static int smp_f6(struct crypto_hash *tfm_cmac, const u8 w[16],
279 const u8 n1[16], u8 n2[16], const u8 r[16],
280 const u8 io_cap[3], const u8 a1[7], const u8 a2[7],
281 u8 res[16])
282{
283 u8 m[65];
284 int err;
285
c7a3d57d
JH		 286 SMP_DBG("w %16phN", w);
287 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
288 SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2);
760b018b
JH		 289
290 memcpy(m, a2, 7);
291 memcpy(m + 7, a1, 7);
292 memcpy(m + 14, io_cap, 3);
293 memcpy(m + 17, r, 16);
294 memcpy(m + 33, n2, 16);
295 memcpy(m + 49, n1, 16);
296
297 err = aes_cmac(tfm_cmac, w, m, sizeof(m), res);
298 if (err)
299 return err;
300
301 BT_DBG("res %16phN", res);
302
303 return err;
304}
305
191dc7fe
JH		 306static int smp_g2(struct crypto_hash *tfm_cmac, const u8 u[32], const u8 v[32],
307 const u8 x[16], const u8 y[16], u32 *val)
308{
309 u8 m[80], tmp[16];
310 int err;
311
c7a3d57d
JH		 312 SMP_DBG("u %32phN", u);
313 SMP_DBG("v %32phN", v);
314 SMP_DBG("x %16phN y %16phN", x, y);
191dc7fe
JH		 315
316 memcpy(m, y, 16);
317 memcpy(m + 16, v, 32);
318 memcpy(m + 48, u, 32);
319
320 err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp);
321 if (err)
322 return err;
323
324 *val = get_unaligned_le32(tmp);
325 *val %= 1000000;
326
c7a3d57d 327 SMP_DBG("val %06u", *val);
191dc7fe
JH		 328
329 return 0;
330}
331
06edf8de
JH		 332static int smp_h6(struct crypto_hash *tfm_cmac, const u8 w[16],
333 const u8 key_id[4], u8 res[16])
334{
335 int err;
336
337 SMP_DBG("w %16phN key_id %4phN", w, key_id);
338
339 err = aes_cmac(tfm_cmac, w, key_id, 4, res);
340 if (err)
341 return err;
342
343 SMP_DBG("res %16phN", res);
344
345 return err;
346}
347
348/* The following functions map to the legacy SMP crypto functions e, c1,
349 * s1 and ah.
350 */
351
d22ef0bc
AB		 352static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r)
353{
354 struct blkcipher_desc desc;
355 struct scatterlist sg;
943a732a 356 uint8_t tmp[16], data[16];
201a5929 357 int err;
d22ef0bc 358
7f376cd6 359 if (!tfm) {
d22ef0bc
AB		 360 BT_ERR("tfm %p", tfm);
361 return -EINVAL;
362 }
363
364 desc.tfm = tfm;
365 desc.flags = 0;
366
943a732a 367 /* The most significant octet of key corresponds to k[0] */
8a2936f4 368 swap_buf(k, tmp, 16);
943a732a
JH		 369
370 err = crypto_blkcipher_setkey(tfm, tmp, 16);
d22ef0bc
AB		 371 if (err) {
372 BT_ERR("cipher setkey failed: %d", err);
373 return err;
374 }
375
943a732a 376 /* Most significant octet of plaintextData corresponds to data[0] */
8a2936f4 377 swap_buf(r, data, 16);
943a732a
JH		 378
379 sg_init_one(&sg, data, 16);
d22ef0bc 380
d22ef0bc
AB		 381 err = crypto_blkcipher_encrypt(&desc, &sg, &sg, 16);
382 if (err)
383 BT_ERR("Encrypt data error %d", err);
384
943a732a 385 /* Most significant octet of encryptedData corresponds to data[0] */
8a2936f4 386 swap_buf(data, r, 16);
943a732a 387
d22ef0bc
AB		 388 return err;
389}
390
06edf8de
JH		 391static int smp_c1(struct crypto_blkcipher *tfm_aes, const u8 k[16],
392 const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat,
393 const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16])
6a77083a 394{
06edf8de 395 u8 p1[16], p2[16];
6a77083a
JH		 396 int err;
397
06edf8de 398 memset(p1, 0, 16);
6a77083a 399
06edf8de
JH		 400 /* p1 = pres || preq || _rat || _iat */
401 p1[0] = _iat;
402 p1[1] = _rat;
403 memcpy(p1 + 2, preq, 7);
404 memcpy(p1 + 9, pres, 7);
405
406 /* p2 = padding || ia || ra */
407 memcpy(p2, ra, 6);
408 memcpy(p2 + 6, ia, 6);
409 memset(p2 + 12, 0, 4);
410
411 /* res = r XOR p1 */
412 u128_xor((u128 *) res, (u128 *) r, (u128 *) p1);
413
414 /* res = e(k, res) */
415 err = smp_e(tfm_aes, k, res);
416 if (err) {
417 BT_ERR("Encrypt data error");
6a77083a 418 return err;
06edf8de 419 }
6a77083a 420
06edf8de
JH		 421 /* res = res XOR p2 */
422 u128_xor((u128 *) res, (u128 *) res, (u128 *) p2);
423
424 /* res = e(k, res) */
425 err = smp_e(tfm_aes, k, res);
426 if (err)
427 BT_ERR("Encrypt data error");
428
429 return err;
430}
431
432static int smp_s1(struct crypto_blkcipher *tfm_aes, const u8 k[16],
433 const u8 r1[16], const u8 r2[16], u8 _r[16])
434{
435 int err;
436
437 /* Just least significant octets from r1 and r2 are considered */
438 memcpy(_r, r2, 8);
439 memcpy(_r + 8, r1, 8);
440
441 err = smp_e(tfm_aes, k, _r);
442 if (err)
443 BT_ERR("Encrypt data error");
6a77083a
JH		 444
445 return err;
446}
447
cd082797
JH		 448static int smp_ah(struct crypto_blkcipher *tfm, const u8 irk[16],
449 const u8 r[3], u8 res[3])
60478054 450{
943a732a 451 u8 _res[16];
60478054
JH		 452 int err;
453
454 /* r' = padding || r */
943a732a
JH		 455 memcpy(_res, r, 3);
456 memset(_res + 3, 0, 13);
60478054 457
943a732a 458 err = smp_e(tfm, irk, _res);
60478054
JH		 459 if (err) {
460 BT_ERR("Encrypt error");
461 return err;
462 }
463
464 /* The output of the random address function ah is:
465 * ah(h, r) = e(k, r') mod 2^24
466 * The output of the security function e is then truncated to 24 bits
467 * by taking the least significant 24 bits of the output of e as the
468 * result of ah.
469 */
943a732a 470 memcpy(res, _res, 3);
60478054
JH		 471
472 return 0;
473}
474
cd082797
JH		 475bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16],
476 const bdaddr_t *bdaddr)
60478054 477{
defce9e8
JH		 478 struct l2cap_chan *chan = hdev->smp_data;
479 struct crypto_blkcipher *tfm;
60478054
JH		 480 u8 hash[3];
481 int err;
482
defce9e8
JH		 483 if (!chan || !chan->data)
484 return false;
485
486 tfm = chan->data;
487
60478054
JH		 488 BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk);
489
490 err = smp_ah(tfm, irk, &bdaddr->b[3], hash);
491 if (err)
492 return false;
493
494 return !memcmp(bdaddr->b, hash, 3);
495}
496
cd082797 497int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa)
b1e2b3ae 498{
defce9e8
JH		 499 struct l2cap_chan *chan = hdev->smp_data;
500 struct crypto_blkcipher *tfm;
b1e2b3ae
JH		 501 int err;
502
defce9e8
JH		 503 if (!chan || !chan->data)
504 return -EOPNOTSUPP;
505
506 tfm = chan->data;
507
b1e2b3ae
JH		 508 get_random_bytes(&rpa->b[3], 3);
509
510 rpa->b[5] &= 0x3f; /* Clear two most significant bits */
511 rpa->b[5] |= 0x40; /* Set second most significant bit */
512
513 err = smp_ah(tfm, irk, &rpa->b[3], rpa->b);
514 if (err < 0)
515 return err;
516
517 BT_DBG("RPA %pMR", rpa);
518
519 return 0;
520}
521
5d88cc73 522static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
eb492e01 523{
5d88cc73 524 struct l2cap_chan *chan = conn->smp;
b68fda68 525 struct smp_chan *smp;
5d88cc73
JH		 526 struct kvec iv[2];
527 struct msghdr msg;
eb492e01 528
5d88cc73
JH		 529 if (!chan)
530 return;
eb492e01 531
5d88cc73 532 BT_DBG("code 0x%2.2x", code);
eb492e01 533
5d88cc73
JH		 534 iv[0].iov_base = &code;
535 iv[0].iov_len = 1;
eb492e01 536
5d88cc73
JH		 537 iv[1].iov_base = data;
538 iv[1].iov_len = len;
eb492e01 539
5d88cc73 540 memset(&msg, 0, sizeof(msg));
eb492e01 541
17836394 542 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iv, 2, 1 + len);
eb492e01 543
5d88cc73 544 l2cap_chan_send(chan, &msg, 1 + len);
e2dcd113 545
b68fda68
JH		 546 if (!chan->data)
547 return;
548
549 smp = chan->data;
550
551 cancel_delayed_work_sync(&smp->security_timer);
1b0921d6 552 schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT);
eb492e01
AB		 553}
554
d2eb9e10 555static u8 authreq_to_seclevel(u8 authreq)
2b64d153 556{
d2eb9e10
JH		 557 if (authreq & SMP_AUTH_MITM) {
558 if (authreq & SMP_AUTH_SC)
559 return BT_SECURITY_FIPS;
560 else
561 return BT_SECURITY_HIGH;
562 } else {
2b64d153 563 return BT_SECURITY_MEDIUM;
d2eb9e10 564 }
2b64d153
BG		 565}
566
567static __u8 seclevel_to_authreq(__u8 sec_level)
568{
569 switch (sec_level) {
d2eb9e10 570 case BT_SECURITY_FIPS:
2b64d153
BG		 571 case BT_SECURITY_HIGH:
572 return SMP_AUTH_MITM | SMP_AUTH_BONDING;
573 case BT_SECURITY_MEDIUM:
574 return SMP_AUTH_BONDING;
575 default:
576 return SMP_AUTH_NONE;
577 }
578}
579
b8e66eac 580static void build_pairing_cmd(struct l2cap_conn *conn,
f1560463
MH		 581 struct smp_cmd_pairing *req,
582 struct smp_cmd_pairing *rsp, __u8 authreq)
b8e66eac 583{
5d88cc73
JH		 584 struct l2cap_chan *chan = conn->smp;
585 struct smp_chan *smp = chan->data;
fd349c02
JH		 586 struct hci_conn *hcon = conn->hcon;
587 struct hci_dev *hdev = hcon->hdev;
02b05bd8 588 u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT;
54790f73 589
b6ae8457 590 if (test_bit(HCI_BONDABLE, &conn->hcon->hdev->dev_flags)) {
7ee4ea36
MH		 591 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
592 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
54790f73 593 authreq |= SMP_AUTH_BONDING;
2b64d153
BG		 594 } else {
595 authreq &= ~SMP_AUTH_BONDING;
54790f73
VCG		 596 }
597
fd349c02
JH		 598 if (test_bit(HCI_RPA_RESOLVING, &hdev->dev_flags))
599 remote_dist |= SMP_DIST_ID_KEY;
600
863efaf2
JH		 601 if (test_bit(HCI_PRIVACY, &hdev->dev_flags))
602 local_dist |= SMP_DIST_ID_KEY;
603
02b05bd8
JH		 604 if (test_bit(HCI_SC_ENABLED, &hdev->dev_flags) &&
605 (authreq & SMP_AUTH_SC)) {
606 struct oob_data *oob_data;
607 u8 bdaddr_type;
608
609 if (test_bit(HCI_SSP_ENABLED, &hdev->dev_flags)) {
df8e1a4c
JH		 610 local_dist |= SMP_DIST_LINK_KEY;
611 remote_dist |= SMP_DIST_LINK_KEY;
612 }
02b05bd8
JH		 613
614 if (hcon->dst_type == ADDR_LE_DEV_PUBLIC)
615 bdaddr_type = BDADDR_LE_PUBLIC;
616 else
617 bdaddr_type = BDADDR_LE_RANDOM;
618
619 oob_data = hci_find_remote_oob_data(hdev, &hcon->dst,
620 bdaddr_type);
621 if (oob_data) {
622 set_bit(SMP_FLAG_OOB, &smp->flags);
623 oob_flag = SMP_OOB_PRESENT;
a29b0733 624 memcpy(smp->rr, oob_data->rand256, 16);
02b05bd8
JH		 625 memcpy(smp->pcnf, oob_data->hash256, 16);
626 }
627
df8e1a4c
JH		 628 } else {
629 authreq &= ~SMP_AUTH_SC;
630 }
631
54790f73
VCG		 632 if (rsp == NULL) {
633 req->io_capability = conn->hcon->io_capability;
02b05bd8 634 req->oob_flag = oob_flag;
54790f73 635 req->max_key_size = SMP_MAX_ENC_KEY_SIZE;
fd349c02
JH		 636 req->init_key_dist = local_dist;
637 req->resp_key_dist = remote_dist;
0edb14de 638 req->auth_req = (authreq & AUTH_REQ_MASK(hdev));
fd349c02
JH		 639
640 smp->remote_key_dist = remote_dist;
54790f73
VCG		 641 return;
642 }
643
644 rsp->io_capability = conn->hcon->io_capability;
02b05bd8 645 rsp->oob_flag = oob_flag;
54790f73 646 rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
fd349c02
JH		 647 rsp->init_key_dist = req->init_key_dist & remote_dist;
648 rsp->resp_key_dist = req->resp_key_dist & local_dist;
0edb14de 649 rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev));
fd349c02
JH		 650
651 smp->remote_key_dist = rsp->init_key_dist;
b8e66eac
VCG		 652}
653
3158c50c
VCG		 654static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)
655{
5d88cc73
JH		 656 struct l2cap_chan *chan = conn->smp;
657 struct smp_chan *smp = chan->data;
1c1def09 658
3158c50c 659 if ((max_key_size > SMP_MAX_ENC_KEY_SIZE) ||
f1560463 660 (max_key_size < SMP_MIN_ENC_KEY_SIZE))
3158c50c
VCG		 661 return SMP_ENC_KEY_SIZE;
662
f7aa611a 663 smp->enc_key_size = max_key_size;
3158c50c
VCG		 664
665 return 0;
666}
667
6f48e260
JH		 668static void smp_chan_destroy(struct l2cap_conn *conn)
669{
670 struct l2cap_chan *chan = conn->smp;
671 struct smp_chan *smp = chan->data;
923e2414 672 struct hci_conn *hcon = conn->hcon;
6f48e260
JH		 673 bool complete;
674
675 BUG_ON(!smp);
676
677 cancel_delayed_work_sync(&smp->security_timer);
6f48e260 678
6f48e260 679 complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags);
923e2414 680 mgmt_smp_complete(hcon, complete);
6f48e260
JH		 681
682 kfree(smp->csrk);
683 kfree(smp->slave_csrk);
6a77083a 684 kfree(smp->link_key);
6f48e260
JH		 685
686 crypto_free_blkcipher(smp->tfm_aes);
407cecf6 687 crypto_free_hash(smp->tfm_cmac);
6f48e260 688
923e2414
JH		 689 /* Ensure that we don't leave any debug key around if debug key
690 * support hasn't been explicitly enabled.
691 */
692 if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG &&
693 !test_bit(HCI_KEEP_DEBUG_KEYS, &hcon->hdev->dev_flags)) {
694 list_del_rcu(&smp->ltk->list);
695 kfree_rcu(smp->ltk, rcu);
696 smp->ltk = NULL;
697 }
698
6f48e260
JH		 699 /* If pairing failed clean up any keys we might have */
700 if (!complete) {
701 if (smp->ltk) {
970d0f1b
JH		 702 list_del_rcu(&smp->ltk->list);
703 kfree_rcu(smp->ltk, rcu);
6f48e260
JH		 704 }
705
706 if (smp->slave_ltk) {
970d0f1b
JH		 707 list_del_rcu(&smp->slave_ltk->list);
708 kfree_rcu(smp->slave_ltk, rcu);
6f48e260
JH		 709 }
710
711 if (smp->remote_irk) {
adae20cb
JH		 712 list_del_rcu(&smp->remote_irk->list);
713 kfree_rcu(smp->remote_irk, rcu);
6f48e260
JH		 714 }
715 }
716
717 chan->data = NULL;
718 kfree(smp);
923e2414 719 hci_conn_drop(hcon);
6f48e260
JH		 720}
721
84794e11 722static void smp_failure(struct l2cap_conn *conn, u8 reason)
4f957a76 723{
bab73cb6 724 struct hci_conn *hcon = conn->hcon;
b68fda68 725 struct l2cap_chan *chan = conn->smp;
bab73cb6 726
84794e11 727 if (reason)
4f957a76 728 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
f1560463 729 &reason);
4f957a76 730
ce39fb4e 731 clear_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags);
e1e930f5 732 mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE);
f1c09c07 733
fc75cc86 734 if (chan->data)
f1c09c07 735 smp_chan_destroy(conn);
4f957a76
BG		 736}
737
2b64d153
BG		 738#define JUST_WORKS 0x00
739#define JUST_CFM 0x01
740#define REQ_PASSKEY 0x02
741#define CFM_PASSKEY 0x03
742#define REQ_OOB 0x04
5e3d3d9b 743#define DSP_PASSKEY 0x05
2b64d153
BG		 744#define OVERLAP 0xFF
745
746static const u8 gen_method[5][5] = {
747 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
748 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
749 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
750 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
751 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP },
752};
753
5e3d3d9b
JH		 754static const u8 sc_method[5][5] = {
755 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
756 { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
757 { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY },
758 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
759 { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
760};
761
581370cc
JH		 762static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io)
763{
2bcd4003
JH		 764 /* If either side has unknown io_caps, use JUST_CFM (which gets
765 * converted later to JUST_WORKS if we're initiators.
766 */
581370cc
JH		 767 if (local_io > SMP_IO_KEYBOARD_DISPLAY ||
768 remote_io > SMP_IO_KEYBOARD_DISPLAY)
2bcd4003 769 return JUST_CFM;
581370cc 770
5e3d3d9b
JH		 771 if (test_bit(SMP_FLAG_SC, &smp->flags))
772 return sc_method[remote_io][local_io];
773
581370cc
JH		 774 return gen_method[remote_io][local_io];
775}
776
2b64d153
BG		 777static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
778 u8 local_io, u8 remote_io)
779{
780 struct hci_conn *hcon = conn->hcon;
5d88cc73
JH		 781 struct l2cap_chan *chan = conn->smp;
782 struct smp_chan *smp = chan->data;
2b64d153
BG		 783 u32 passkey = 0;
784 int ret = 0;
785
786 /* Initialize key for JUST WORKS */
787 memset(smp->tk, 0, sizeof(smp->tk));
4a74d658 788 clear_bit(SMP_FLAG_TK_VALID, &smp->flags);
2b64d153
BG		 789
790 BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io);
791
2bcd4003
JH		 792 /* If neither side wants MITM, either "just" confirm an incoming
793 * request or use just-works for outgoing ones. The JUST_CFM
794 * will be converted to JUST_WORKS if necessary later in this
795 * function. If either side has MITM look up the method from the
796 * table.
797 */
581370cc 798 if (!(auth & SMP_AUTH_MITM))
783e0574 799 smp->method = JUST_CFM;
2b64d153 800 else
783e0574 801 smp->method = get_auth_method(smp, local_io, remote_io);
2b64d153 802
a82505c7 803 /* Don't confirm locally initiated pairing attempts */
783e0574
JH		 804 if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR,
805 &smp->flags))
806 smp->method = JUST_WORKS;
a82505c7 807
02f3e254 808 /* Don't bother user space with no IO capabilities */
783e0574
JH		 809 if (smp->method == JUST_CFM &&
810 hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
811 smp->method = JUST_WORKS;
02f3e254 812
2b64d153 813 /* If Just Works, Continue with Zero TK */
783e0574 814 if (smp->method == JUST_WORKS) {
4a74d658 815 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
2b64d153
BG		 816 return 0;
817 }
818
819 /* Not Just Works/Confirm results in MITM Authentication */
783e0574 820 if (smp->method != JUST_CFM) {
4a74d658 821 set_bit(SMP_FLAG_MITM_AUTH, &smp->flags);
5eb596f5
JH		 822 if (hcon->pending_sec_level < BT_SECURITY_HIGH)
823 hcon->pending_sec_level = BT_SECURITY_HIGH;
824 }
2b64d153
BG		 825
826 /* If both devices have Keyoard-Display I/O, the master
827 * Confirms and the slave Enters the passkey.
828 */
783e0574 829 if (smp->method == OVERLAP) {
40bef302 830 if (hcon->role == HCI_ROLE_MASTER)
783e0574 831 smp->method = CFM_PASSKEY;
2b64d153 832 else
783e0574 833 smp->method = REQ_PASSKEY;
2b64d153
BG		 834 }
835
01ad34d2 836 /* Generate random passkey. */
783e0574 837 if (smp->method == CFM_PASSKEY) {
943a732a 838 memset(smp->tk, 0, sizeof(smp->tk));
2b64d153
BG		 839 get_random_bytes(&passkey, sizeof(passkey));
840 passkey %= 1000000;
943a732a 841 put_unaligned_le32(passkey, smp->tk);
2b64d153 842 BT_DBG("PassKey: %d", passkey);
4a74d658 843 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
2b64d153
BG		 844 }
845
783e0574 846 if (smp->method == REQ_PASSKEY)
ce39fb4e 847 ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst,
272d90df 848 hcon->type, hcon->dst_type);
783e0574 849 else if (smp->method == JUST_CFM)
4eb65e66
JH		 850 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
851 hcon->type, hcon->dst_type,
852 passkey, 1);
2b64d153 853 else
01ad34d2 854 ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst,
272d90df 855 hcon->type, hcon->dst_type,
39adbffe 856 passkey, 0);
2b64d153 857
2b64d153
BG		 858 return ret;
859}
860
1cc61144 861static u8 smp_confirm(struct smp_chan *smp)
8aab4757 862{
8aab4757 863 struct l2cap_conn *conn = smp->conn;
8aab4757
VCG		 864 struct smp_cmd_pairing_confirm cp;
865 int ret;
8aab4757
VCG		 866
867 BT_DBG("conn %p", conn);
868
e491eaf3 869 ret = smp_c1(smp->tfm_aes, smp->tk, smp->prnd, smp->preq, smp->prsp,
b1cd5fd9 870 conn->hcon->init_addr_type, &conn->hcon->init_addr,
943a732a
JH		 871 conn->hcon->resp_addr_type, &conn->hcon->resp_addr,
872 cp.confirm_val);
1cc61144
JH		 873 if (ret)
874 return SMP_UNSPECIFIED;
8aab4757 875
4a74d658 876 clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
2b64d153 877
8aab4757
VCG		 878 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
879
b28b4943
JH		 880 if (conn->hcon->out)
881 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
882 else
883 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
884
1cc61144 885 return 0;
8aab4757
VCG		 886}
887
861580a9 888static u8 smp_random(struct smp_chan *smp)
8aab4757 889{
8aab4757
VCG		 890 struct l2cap_conn *conn = smp->conn;
891 struct hci_conn *hcon = conn->hcon;
861580a9 892 u8 confirm[16];
8aab4757
VCG		 893 int ret;
894
ec70f36f 895 if (IS_ERR_OR_NULL(smp->tfm_aes))
861580a9 896 return SMP_UNSPECIFIED;
8aab4757
VCG		 897
898 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
899
e491eaf3 900 ret = smp_c1(smp->tfm_aes, smp->tk, smp->rrnd, smp->preq, smp->prsp,
b1cd5fd9 901 hcon->init_addr_type, &hcon->init_addr,
943a732a 902 hcon->resp_addr_type, &hcon->resp_addr, confirm);
861580a9
JH		 903 if (ret)
904 return SMP_UNSPECIFIED;
8aab4757 905
8aab4757
VCG		 906 if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) {
907 BT_ERR("Pairing failed (confirmation values mismatch)");
861580a9 908 return SMP_CONFIRM_FAILED;
8aab4757
VCG		 909 }
910
911 if (hcon->out) {
fe39c7b2
MH		 912 u8 stk[16];
913 __le64 rand = 0;
914 __le16 ediv = 0;
8aab4757 915
e491eaf3 916 smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk);
8aab4757 917
f7aa611a 918 memset(stk + smp->enc_key_size, 0,
04124681 919 SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size);
8aab4757 920
861580a9
JH		 921 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
922 return SMP_UNSPECIFIED;
8aab4757
VCG		 923
924 hci_le_start_enc(hcon, ediv, rand, stk);
f7aa611a 925 hcon->enc_key_size = smp->enc_key_size;
fe59a05f 926 set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
8aab4757 927 } else {
fff3490f 928 u8 stk[16], auth;
fe39c7b2
MH		 929 __le64 rand = 0;
930 __le16 ediv = 0;
8aab4757 931
943a732a
JH		 932 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
933 smp->prnd);
8aab4757 934
e491eaf3 935 smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk);
8aab4757 936
f7aa611a 937 memset(stk + smp->enc_key_size, 0,
f1560463 938 SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size);
8aab4757 939
fff3490f
JH		 940 if (hcon->pending_sec_level == BT_SECURITY_HIGH)
941 auth = 1;
942 else
943 auth = 0;
944
7d5843b7
JH		 945 /* Even though there's no _SLAVE suffix this is the
946 * slave STK we're adding for later lookup (the master
947 * STK never needs to be stored).
948 */
ce39fb4e 949 hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
2ceba539 950 SMP_STK, auth, stk, smp->enc_key_size, ediv, rand);
8aab4757
VCG		 951 }
952
861580a9 953 return 0;
8aab4757
VCG		 954}
955
44f1a7ab
JH		 956static void smp_notify_keys(struct l2cap_conn *conn)
957{
958 struct l2cap_chan *chan = conn->smp;
959 struct smp_chan *smp = chan->data;
960 struct hci_conn *hcon = conn->hcon;
961 struct hci_dev *hdev = hcon->hdev;
962 struct smp_cmd_pairing *req = (void *) &smp->preq[1];
963 struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1];
964 bool persistent;
965
966 if (smp->remote_irk) {
967 mgmt_new_irk(hdev, smp->remote_irk);
968 /* Now that user space can be considered to know the
969 * identity address track the connection based on it
b5ae344d 970 * from now on (assuming this is an LE link).
44f1a7ab 971 */
b5ae344d
JH		 972 if (hcon->type == LE_LINK) {
973 bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
974 hcon->dst_type = smp->remote_irk->addr_type;
975 queue_work(hdev->workqueue, &conn->id_addr_update_work);
976 }
44f1a7ab
JH		 977
978 /* When receiving an indentity resolving key for
979 * a remote device that does not use a resolvable
980 * private address, just remove the key so that
981 * it is possible to use the controller white
982 * list for scanning.
983 *
984 * Userspace will have been told to not store
985 * this key at this point. So it is safe to
986 * just remove it.
987 */
988 if (!bacmp(&smp->remote_irk->rpa, BDADDR_ANY)) {
adae20cb
JH		 989 list_del_rcu(&smp->remote_irk->list);
990 kfree_rcu(smp->remote_irk, rcu);
44f1a7ab
JH		 991 smp->remote_irk = NULL;
992 }
993 }
994
b5ae344d
JH		 995 if (hcon->type == ACL_LINK) {
996 if (hcon->key_type == HCI_LK_DEBUG_COMBINATION)
997 persistent = false;
998 else
999 persistent = !test_bit(HCI_CONN_FLUSH_KEY,
1000 &hcon->flags);
1001 } else {
1002 /* The LTKs and CSRKs should be persistent only if both sides
1003 * had the bonding bit set in their authentication requests.
1004 */
1005 persistent = !!((req->auth_req & rsp->auth_req) &
1006 SMP_AUTH_BONDING);
1007 }
1008
44f1a7ab
JH		 1009
1010 if (smp->csrk) {
1011 smp->csrk->bdaddr_type = hcon->dst_type;
1012 bacpy(&smp->csrk->bdaddr, &hcon->dst);
1013 mgmt_new_csrk(hdev, smp->csrk, persistent);
1014 }
1015
1016 if (smp->slave_csrk) {
1017 smp->slave_csrk->bdaddr_type = hcon->dst_type;
1018 bacpy(&smp->slave_csrk->bdaddr, &hcon->dst);
1019 mgmt_new_csrk(hdev, smp->slave_csrk, persistent);
1020 }
1021
1022 if (smp->ltk) {
1023 smp->ltk->bdaddr_type = hcon->dst_type;
1024 bacpy(&smp->ltk->bdaddr, &hcon->dst);
1025 mgmt_new_ltk(hdev, smp->ltk, persistent);
1026 }
1027
1028 if (smp->slave_ltk) {
1029 smp->slave_ltk->bdaddr_type = hcon->dst_type;
1030 bacpy(&smp->slave_ltk->bdaddr, &hcon->dst);
1031 mgmt_new_ltk(hdev, smp->slave_ltk, persistent);
1032 }
6a77083a
JH		 1033
1034 if (smp->link_key) {
e3befab9
JH		 1035 struct link_key *key;
1036 u8 type;
1037
1038 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1039 type = HCI_LK_DEBUG_COMBINATION;
1040 else if (hcon->sec_level == BT_SECURITY_FIPS)
1041 type = HCI_LK_AUTH_COMBINATION_P256;
1042 else
1043 type = HCI_LK_UNAUTH_COMBINATION_P256;
1044
1045 key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst,
1046 smp->link_key, type, 0, &persistent);
1047 if (key) {
1048 mgmt_new_link_key(hdev, key, persistent);
1049
1050 /* Don't keep debug keys around if the relevant
1051 * flag is not set.
1052 */
1053 if (!test_bit(HCI_KEEP_DEBUG_KEYS, &hdev->dev_flags) &&
1054 key->type == HCI_LK_DEBUG_COMBINATION) {
1055 list_del_rcu(&key->list);
1056 kfree_rcu(key, rcu);
1057 }
1058 }
6a77083a
JH		 1059 }
1060}
1061
d3e54a87
JH		 1062static void sc_add_ltk(struct smp_chan *smp)
1063{
1064 struct hci_conn *hcon = smp->conn->hcon;
1065 u8 key_type, auth;
1066
1067 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1068 key_type = SMP_LTK_P256_DEBUG;
1069 else
1070 key_type = SMP_LTK_P256;
1071
1072 if (hcon->pending_sec_level == BT_SECURITY_FIPS)
1073 auth = 1;
1074 else
1075 auth = 0;
1076
1077 memset(smp->tk + smp->enc_key_size, 0,
1078 SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size);
1079
1080 smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1081 key_type, auth, smp->tk, smp->enc_key_size,
1082 0, 0);
1083}
1084
6a77083a
JH		 1085static void sc_generate_link_key(struct smp_chan *smp)
1086{
1087 /* These constants are as specified in the core specification.
1088 * In ASCII they spell out to 'tmp1' and 'lebr'.
1089 */
1090 const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 };
1091 const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c };
1092
1093 smp->link_key = kzalloc(16, GFP_KERNEL);
1094 if (!smp->link_key)
1095 return;
1096
1097 if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) {
1098 kfree(smp->link_key);
1099 smp->link_key = NULL;
1100 return;
1101 }
1102
1103 if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) {
1104 kfree(smp->link_key);
1105 smp->link_key = NULL;
1106 return;
1107 }
44f1a7ab
JH		 1108}
1109
b28b4943
JH		 1110static void smp_allow_key_dist(struct smp_chan *smp)
1111{
1112 /* Allow the first expected phase 3 PDU. The rest of the PDUs
1113 * will be allowed in each PDU handler to ensure we receive
1114 * them in the correct order.
1115 */
1116 if (smp->remote_key_dist & SMP_DIST_ENC_KEY)
1117 SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO);
1118 else if (smp->remote_key_dist & SMP_DIST_ID_KEY)
1119 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
1120 else if (smp->remote_key_dist & SMP_DIST_SIGN)
1121 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
1122}
1123
b5ae344d
JH		 1124static void sc_generate_ltk(struct smp_chan *smp)
1125{
1126 /* These constants are as specified in the core specification.
1127 * In ASCII they spell out to 'tmp2' and 'brle'.
1128 */
1129 const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 };
1130 const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 };
1131 struct hci_conn *hcon = smp->conn->hcon;
1132 struct hci_dev *hdev = hcon->hdev;
1133 struct link_key *key;
1134
1135 key = hci_find_link_key(hdev, &hcon->dst);
1136 if (!key) {
1137 BT_ERR("%s No Link Key found to generate LTK", hdev->name);
1138 return;
1139 }
1140
1141 if (key->type == HCI_LK_DEBUG_COMBINATION)
1142 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1143
1144 if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk))
1145 return;
1146
1147 if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk))
1148 return;
1149
1150 sc_add_ltk(smp);
1151}
1152
d6268e86 1153static void smp_distribute_keys(struct smp_chan *smp)
44f1a7ab
JH		 1154{
1155 struct smp_cmd_pairing *req, *rsp;
86d1407c 1156 struct l2cap_conn *conn = smp->conn;
44f1a7ab
JH		 1157 struct hci_conn *hcon = conn->hcon;
1158 struct hci_dev *hdev = hcon->hdev;
1159 __u8 *keydist;
1160
1161 BT_DBG("conn %p", conn);
1162
44f1a7ab
JH		 1163 rsp = (void *) &smp->prsp[1];
1164
1165 /* The responder sends its keys first */
b28b4943
JH		 1166 if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) {
1167 smp_allow_key_dist(smp);
86d1407c 1168 return;
b28b4943 1169 }
44f1a7ab
JH		 1170
1171 req = (void *) &smp->preq[1];
1172
1173 if (hcon->out) {
1174 keydist = &rsp->init_key_dist;
1175 *keydist &= req->init_key_dist;
1176 } else {
1177 keydist = &rsp->resp_key_dist;
1178 *keydist &= req->resp_key_dist;
1179 }
1180
6a77083a 1181 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
b5ae344d 1182 if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY))
6a77083a 1183 sc_generate_link_key(smp);
b5ae344d
JH		 1184 if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY))
1185 sc_generate_ltk(smp);
6a77083a
JH		 1186
1187 /* Clear the keys which are generated but not distributed */
1188 *keydist &= ~SMP_SC_NO_DIST;
1189 }
1190
44f1a7ab
JH		 1191 BT_DBG("keydist 0x%x", *keydist);
1192
1193 if (*keydist & SMP_DIST_ENC_KEY) {
1194 struct smp_cmd_encrypt_info enc;
1195 struct smp_cmd_master_ident ident;
1196 struct smp_ltk *ltk;
1197 u8 authenticated;
1198 __le16 ediv;
1199 __le64 rand;
1200
1201 get_random_bytes(enc.ltk, sizeof(enc.ltk));
1202 get_random_bytes(&ediv, sizeof(ediv));
1203 get_random_bytes(&rand, sizeof(rand));
1204
1205 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);
1206
1207 authenticated = hcon->sec_level == BT_SECURITY_HIGH;
1208 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type,
1209 SMP_LTK_SLAVE, authenticated, enc.ltk,
1210 smp->enc_key_size, ediv, rand);
1211 smp->slave_ltk = ltk;
1212
1213 ident.ediv = ediv;
1214 ident.rand = rand;
1215
1216 smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident);
1217
1218 *keydist &= ~SMP_DIST_ENC_KEY;
1219 }
1220
1221 if (*keydist & SMP_DIST_ID_KEY) {
1222 struct smp_cmd_ident_addr_info addrinfo;
1223 struct smp_cmd_ident_info idinfo;
1224
1225 memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk));
1226
1227 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);
1228
1229 /* The hci_conn contains the local identity address
1230 * after the connection has been established.
1231 *
1232 * This is true even when the connection has been
1233 * established using a resolvable random address.
1234 */
1235 bacpy(&addrinfo.bdaddr, &hcon->src);
1236 addrinfo.addr_type = hcon->src_type;
1237
1238 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo),
1239 &addrinfo);
1240
1241 *keydist &= ~SMP_DIST_ID_KEY;
1242 }
1243
1244 if (*keydist & SMP_DIST_SIGN) {
1245 struct smp_cmd_sign_info sign;
1246 struct smp_csrk *csrk;
1247
1248 /* Generate a new random key */
1249 get_random_bytes(sign.csrk, sizeof(sign.csrk));
1250
1251 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
1252 if (csrk) {
1253 csrk->master = 0x00;
1254 memcpy(csrk->val, sign.csrk, sizeof(csrk->val));
1255 }
1256 smp->slave_csrk = csrk;
1257
1258 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);
1259
1260 *keydist &= ~SMP_DIST_SIGN;
1261 }
1262
1263 /* If there are still keys to be received wait for them */
b28b4943
JH		 1264 if (smp->remote_key_dist & KEY_DIST_MASK) {
1265 smp_allow_key_dist(smp);
86d1407c 1266 return;
b28b4943 1267 }
44f1a7ab 1268
44f1a7ab
JH		 1269 set_bit(SMP_FLAG_COMPLETE, &smp->flags);
1270 smp_notify_keys(conn);
1271
1272 smp_chan_destroy(conn);
44f1a7ab
JH		 1273}
1274
b68fda68
JH		 1275static void smp_timeout(struct work_struct *work)
1276{
1277 struct smp_chan *smp = container_of(work, struct smp_chan,
1278 security_timer.work);
1279 struct l2cap_conn *conn = smp->conn;
1280
1281 BT_DBG("conn %p", conn);
1282
1e91c29e 1283 hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM);
b68fda68
JH		 1284}
1285
8aab4757
VCG		 1286static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
1287{
5d88cc73 1288 struct l2cap_chan *chan = conn->smp;
8aab4757
VCG		 1289 struct smp_chan *smp;
1290
f1560463 1291 smp = kzalloc(sizeof(*smp), GFP_ATOMIC);
fc75cc86 1292 if (!smp)
8aab4757
VCG		 1293 return NULL;
1294
6a7bd103
JH		 1295 smp->tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
1296 if (IS_ERR(smp->tfm_aes)) {
1297 BT_ERR("Unable to create ECB crypto context");
1298 kfree(smp);
1299 return NULL;
1300 }
1301
407cecf6
JH		 1302 smp->tfm_cmac = crypto_alloc_hash("cmac(aes)", 0, CRYPTO_ALG_ASYNC);
1303 if (IS_ERR(smp->tfm_cmac)) {
1304 BT_ERR("Unable to create CMAC crypto context");
1305 crypto_free_blkcipher(smp->tfm_aes);
1306 kfree(smp);
1307 return NULL;
1308 }
1309
8aab4757 1310 smp->conn = conn;
5d88cc73 1311 chan->data = smp;
8aab4757 1312
b28b4943
JH		 1313 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL);
1314
b68fda68
JH		 1315 INIT_DELAYED_WORK(&smp->security_timer, smp_timeout);
1316
8aab4757
VCG		 1317 hci_conn_hold(conn->hcon);
1318
1319 return smp;
1320}
1321
760b018b
JH		 1322static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16])
1323{
1324 struct hci_conn *hcon = smp->conn->hcon;
1325 u8 *na, *nb, a[7], b[7];
1326
1327 if (hcon->out) {
1328 na = smp->prnd;
1329 nb = smp->rrnd;
1330 } else {
1331 na = smp->rrnd;
1332 nb = smp->prnd;
1333 }
1334
1335 memcpy(a, &hcon->init_addr, 6);
1336 memcpy(b, &hcon->resp_addr, 6);
1337 a[6] = hcon->init_addr_type;
1338 b[6] = hcon->resp_addr_type;
1339
1340 return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk);
1341}
1342
38606f14 1343static void sc_dhkey_check(struct smp_chan *smp)
760b018b
JH		 1344{
1345 struct hci_conn *hcon = smp->conn->hcon;
1346 struct smp_cmd_dhkey_check check;
1347 u8 a[7], b[7], *local_addr, *remote_addr;
1348 u8 io_cap[3], r[16];
1349
760b018b
JH		 1350 memcpy(a, &hcon->init_addr, 6);
1351 memcpy(b, &hcon->resp_addr, 6);
1352 a[6] = hcon->init_addr_type;
1353 b[6] = hcon->resp_addr_type;
1354
1355 if (hcon->out) {
1356 local_addr = a;
1357 remote_addr = b;
1358 memcpy(io_cap, &smp->preq[1], 3);
1359 } else {
1360 local_addr = b;
1361 remote_addr = a;
1362 memcpy(io_cap, &smp->prsp[1], 3);
1363 }
1364
dddd3059
JH		 1365 memset(r, 0, sizeof(r));
1366
1367 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
38606f14 1368 put_unaligned_le32(hcon->passkey_notify, r);
760b018b 1369
a29b0733
JH		 1370 if (smp->method == REQ_OOB)
1371 memcpy(r, smp->rr, 16);
1372
760b018b
JH		 1373 smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap,
1374 local_addr, remote_addr, check.e);
1375
1376 smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check);
dddd3059
JH		 1377}
1378
38606f14
JH		 1379static u8 sc_passkey_send_confirm(struct smp_chan *smp)
1380{
1381 struct l2cap_conn *conn = smp->conn;
1382 struct hci_conn *hcon = conn->hcon;
1383 struct smp_cmd_pairing_confirm cfm;
1384 u8 r;
1385
1386 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1387 r |= 0x80;
1388
1389 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1390
1391 if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r,
1392 cfm.confirm_val))
1393 return SMP_UNSPECIFIED;
1394
1395 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
1396
1397 return 0;
1398}
1399
1400static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op)
1401{
1402 struct l2cap_conn *conn = smp->conn;
1403 struct hci_conn *hcon = conn->hcon;
1404 struct hci_dev *hdev = hcon->hdev;
1405 u8 cfm[16], r;
1406
1407 /* Ignore the PDU if we've already done 20 rounds (0 - 19) */
1408 if (smp->passkey_round >= 20)
1409 return 0;
1410
1411 switch (smp_op) {
1412 case SMP_CMD_PAIRING_RANDOM:
1413 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1414 r |= 0x80;
1415
1416 if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
1417 smp->rrnd, r, cfm))
1418 return SMP_UNSPECIFIED;
1419
1420 if (memcmp(smp->pcnf, cfm, 16))
1421 return SMP_CONFIRM_FAILED;
1422
1423 smp->passkey_round++;
1424
1425 if (smp->passkey_round == 20) {
1426 /* Generate MacKey and LTK */
1427 if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk))
1428 return SMP_UNSPECIFIED;
1429 }
1430
1431 /* The round is only complete when the initiator
1432 * receives pairing random.
1433 */
1434 if (!hcon->out) {
1435 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1436 sizeof(smp->prnd), smp->prnd);
d3e54a87 1437 if (smp->passkey_round == 20)
38606f14 1438 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
d3e54a87 1439 else
38606f14 1440 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
38606f14
JH		 1441 return 0;
1442 }
1443
1444 /* Start the next round */
1445 if (smp->passkey_round != 20)
1446 return sc_passkey_round(smp, 0);
1447
1448 /* Passkey rounds are complete - start DHKey Check */
1449 sc_dhkey_check(smp);
1450 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1451
1452 break;
1453
1454 case SMP_CMD_PAIRING_CONFIRM:
1455 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
1456 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
1457 return 0;
1458 }
1459
1460 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1461
1462 if (hcon->out) {
1463 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1464 sizeof(smp->prnd), smp->prnd);
1465 return 0;
1466 }
1467
1468 return sc_passkey_send_confirm(smp);
1469
1470 case SMP_CMD_PUBLIC_KEY:
1471 default:
1472 /* Initiating device starts the round */
1473 if (!hcon->out)
1474 return 0;
1475
1476 BT_DBG("%s Starting passkey round %u", hdev->name,
1477 smp->passkey_round + 1);
1478
1479 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1480
1481 return sc_passkey_send_confirm(smp);
1482 }
1483
1484 return 0;
1485}
1486
dddd3059
JH		 1487static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey)
1488{
38606f14
JH		 1489 struct l2cap_conn *conn = smp->conn;
1490 struct hci_conn *hcon = conn->hcon;
1491 u8 smp_op;
1492
1493 clear_bit(SMP_FLAG_WAIT_USER, &smp->flags);
1494
dddd3059
JH		 1495 switch (mgmt_op) {
1496 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1497 smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED);
1498 return 0;
1499 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1500 smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED);
1501 return 0;
38606f14
JH		 1502 case MGMT_OP_USER_PASSKEY_REPLY:
1503 hcon->passkey_notify = le32_to_cpu(passkey);
1504 smp->passkey_round = 0;
1505
1506 if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags))
1507 smp_op = SMP_CMD_PAIRING_CONFIRM;
1508 else
1509 smp_op = 0;
1510
1511 if (sc_passkey_round(smp, smp_op))
1512 return -EIO;
1513
1514 return 0;
dddd3059
JH		 1515 }
1516
d3e54a87
JH		 1517 /* Initiator sends DHKey check first */
1518 if (hcon->out) {
1519 sc_dhkey_check(smp);
1520 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1521 } else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) {
1522 sc_dhkey_check(smp);
1523 sc_add_ltk(smp);
1524 }
760b018b
JH		 1525
1526 return 0;
1527}
1528
2b64d153
BG		 1529int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
1530{
b10e8017 1531 struct l2cap_conn *conn = hcon->l2cap_data;
5d88cc73 1532 struct l2cap_chan *chan;
2b64d153
BG		 1533 struct smp_chan *smp;
1534 u32 value;
fc75cc86 1535 int err;
2b64d153
BG		 1536
1537 BT_DBG("");
1538
fc75cc86 1539 if (!conn)
2b64d153
BG		 1540 return -ENOTCONN;
1541
5d88cc73
JH		 1542 chan = conn->smp;
1543 if (!chan)
1544 return -ENOTCONN;
1545
fc75cc86
JH		 1546 l2cap_chan_lock(chan);
1547 if (!chan->data) {
1548 err = -ENOTCONN;
1549 goto unlock;
1550 }
1551
5d88cc73 1552 smp = chan->data;
2b64d153 1553
760b018b
JH		 1554 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1555 err = sc_user_reply(smp, mgmt_op, passkey);
1556 goto unlock;
1557 }
1558
2b64d153
BG		 1559 switch (mgmt_op) {
1560 case MGMT_OP_USER_PASSKEY_REPLY:
1561 value = le32_to_cpu(passkey);
943a732a 1562 memset(smp->tk, 0, sizeof(smp->tk));
2b64d153 1563 BT_DBG("PassKey: %d", value);
943a732a 1564 put_unaligned_le32(value, smp->tk);
2b64d153
BG		 1565 /* Fall Through */
1566 case MGMT_OP_USER_CONFIRM_REPLY:
4a74d658 1567 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
2b64d153
BG		 1568 break;
1569 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1570 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
84794e11 1571 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
fc75cc86
JH		 1572 err = 0;
1573 goto unlock;
2b64d153 1574 default:
84794e11 1575 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
fc75cc86
JH		 1576 err = -EOPNOTSUPP;
1577 goto unlock;
2b64d153
BG		 1578 }
1579
fc75cc86
JH		 1580 err = 0;
1581
2b64d153 1582 /* If it is our turn to send Pairing Confirm, do so now */
1cc61144
JH		 1583 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) {
1584 u8 rsp = smp_confirm(smp);
1585 if (rsp)
1586 smp_failure(conn, rsp);
1587 }
2b64d153 1588
fc75cc86
JH		 1589unlock:
1590 l2cap_chan_unlock(chan);
1591 return err;
2b64d153
BG		 1592}
1593
b5ae344d
JH		 1594static void build_bredr_pairing_cmd(struct smp_chan *smp,
1595 struct smp_cmd_pairing *req,
1596 struct smp_cmd_pairing *rsp)
1597{
1598 struct l2cap_conn *conn = smp->conn;
1599 struct hci_dev *hdev = conn->hcon->hdev;
1600 u8 local_dist = 0, remote_dist = 0;
1601
1602 if (test_bit(HCI_BONDABLE, &hdev->dev_flags)) {
1603 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1604 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1605 }
1606
1607 if (test_bit(HCI_RPA_RESOLVING, &hdev->dev_flags))
1608 remote_dist |= SMP_DIST_ID_KEY;
1609
1610 if (test_bit(HCI_PRIVACY, &hdev->dev_flags))
1611 local_dist |= SMP_DIST_ID_KEY;
1612
1613 if (!rsp) {
1614 memset(req, 0, sizeof(*req));
1615
1616 req->init_key_dist = local_dist;
1617 req->resp_key_dist = remote_dist;
1618 req->max_key_size = SMP_MAX_ENC_KEY_SIZE;
1619
1620 smp->remote_key_dist = remote_dist;
1621
1622 return;
1623 }
1624
1625 memset(rsp, 0, sizeof(*rsp));
1626
1627 rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
1628 rsp->init_key_dist = req->init_key_dist & remote_dist;
1629 rsp->resp_key_dist = req->resp_key_dist & local_dist;
1630
1631 smp->remote_key_dist = rsp->init_key_dist;
1632}
1633
da85e5e5 1634static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
88ba43b6 1635{
3158c50c 1636 struct smp_cmd_pairing rsp, *req = (void *) skb->data;
fc75cc86 1637 struct l2cap_chan *chan = conn->smp;
b3c6410b 1638 struct hci_dev *hdev = conn->hcon->hdev;
8aab4757 1639 struct smp_chan *smp;
c7262e71 1640 u8 key_size, auth, sec_level;
8aab4757 1641 int ret;
88ba43b6
AB		 1642
1643 BT_DBG("conn %p", conn);
1644
c46b98be 1645 if (skb->len < sizeof(*req))
38e4a915 1646 return SMP_INVALID_PARAMS;
c46b98be 1647
40bef302 1648 if (conn->hcon->role != HCI_ROLE_SLAVE)
2b64d153
BG		 1649 return SMP_CMD_NOTSUPP;
1650
fc75cc86 1651 if (!chan->data)
8aab4757 1652 smp = smp_chan_create(conn);
fc75cc86 1653 else
5d88cc73 1654 smp = chan->data;
8aab4757 1655
d08fd0e7
AE		 1656 if (!smp)
1657 return SMP_UNSPECIFIED;
d26a2345 1658
c05b9339 1659 /* We didn't start the pairing, so match remote */
0edb14de 1660 auth = req->auth_req & AUTH_REQ_MASK(hdev);
c05b9339 1661
b6ae8457 1662 if (!test_bit(HCI_BONDABLE, &hdev->dev_flags) &&
c05b9339 1663 (auth & SMP_AUTH_BONDING))
b3c6410b
JH		 1664 return SMP_PAIRING_NOTSUPP;
1665
903b71c7
JH		 1666 if (test_bit(HCI_SC_ONLY, &hdev->dev_flags) && !(auth & SMP_AUTH_SC))
1667 return SMP_AUTH_REQUIREMENTS;
1668
1c1def09
VCG		 1669 smp->preq[0] = SMP_CMD_PAIRING_REQ;
1670 memcpy(&smp->preq[1], req, sizeof(*req));
3158c50c 1671 skb_pull(skb, sizeof(*req));
88ba43b6 1672
b5ae344d
JH		 1673 /* SMP over BR/EDR requires special treatment */
1674 if (conn->hcon->type == ACL_LINK) {
1675 /* We must have a BR/EDR SC link */
08f63cc5
MH		 1676 if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) &&
1677 !test_bit(HCI_FORCE_LESC, &hdev->dbg_flags))
b5ae344d
JH		 1678 return SMP_CROSS_TRANSP_NOT_ALLOWED;
1679
1680 set_bit(SMP_FLAG_SC, &smp->flags);
1681
1682 build_bredr_pairing_cmd(smp, req, &rsp);
1683
1684 key_size = min(req->max_key_size, rsp.max_key_size);
1685 if (check_enc_key_size(conn, key_size))
1686 return SMP_ENC_KEY_SIZE;
1687
1688 /* Clear bits which are generated but not distributed */
1689 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1690
1691 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1692 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1693 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1694
1695 smp_distribute_keys(smp);
1696 return 0;
1697 }
1698
5e3d3d9b
JH		 1699 build_pairing_cmd(conn, req, &rsp, auth);
1700
1701 if (rsp.auth_req & SMP_AUTH_SC)
1702 set_bit(SMP_FLAG_SC, &smp->flags);
1703
5be5e275 1704 if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
1afc2a1a
JH		 1705 sec_level = BT_SECURITY_MEDIUM;
1706 else
1707 sec_level = authreq_to_seclevel(auth);
1708
c7262e71
JH		 1709 if (sec_level > conn->hcon->pending_sec_level)
1710 conn->hcon->pending_sec_level = sec_level;
fdde0a26 1711
49c922bb 1712 /* If we need MITM check that it can be achieved */
2ed8f65c
JH		 1713 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1714 u8 method;
1715
1716 method = get_auth_method(smp, conn->hcon->io_capability,
1717 req->io_capability);
1718 if (method == JUST_WORKS || method == JUST_CFM)
1719 return SMP_AUTH_REQUIREMENTS;
1720 }
1721
3158c50c
VCG		 1722 key_size = min(req->max_key_size, rsp.max_key_size);
1723 if (check_enc_key_size(conn, key_size))
1724 return SMP_ENC_KEY_SIZE;
88ba43b6 1725
e84a6b13 1726 get_random_bytes(smp->prnd, sizeof(smp->prnd));
8aab4757 1727
1c1def09
VCG		 1728 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1729 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
f01ead31 1730
3158c50c 1731 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
3b19146d
JH		 1732
1733 clear_bit(SMP_FLAG_INITIATOR, &smp->flags);
1734
1735 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1736 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
1737 /* Clear bits which are generated but not distributed */
1738 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1739 /* Wait for Public Key from Initiating Device */
1740 return 0;
1741 } else {
1742 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1743 }
da85e5e5 1744
2b64d153
BG		 1745 /* Request setup of TK */
1746 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability);
1747 if (ret)
1748 return SMP_UNSPECIFIED;
1749
da85e5e5 1750 return 0;
88ba43b6
AB		 1751}
1752
3b19146d
JH		 1753static u8 sc_send_public_key(struct smp_chan *smp)
1754{
70157ef5
JH		 1755 struct hci_dev *hdev = smp->conn->hcon->hdev;
1756
3b19146d
JH		 1757 BT_DBG("");
1758
70157ef5
JH		 1759 if (test_bit(HCI_USE_DEBUG_KEYS, &hdev->dev_flags)) {
1760 BT_DBG("Using debug keys");
1761 memcpy(smp->local_pk, debug_pk, 64);
1762 memcpy(smp->local_sk, debug_sk, 32);
1763 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1764 } else {
1765 while (true) {
1766 /* Generate local key pair for Secure Connections */
1767 if (!ecc_make_key(smp->local_pk, smp->local_sk))
1768 return SMP_UNSPECIFIED;
6c0dcc50 1769
70157ef5
JH		 1770 /* This is unlikely, but we need to check that
1771 * we didn't accidentially generate a debug key.
1772 */
1773 if (memcmp(smp->local_sk, debug_sk, 32))
1774 break;
1775 }
6c0dcc50 1776 }
3b19146d 1777
c7a3d57d
JH		 1778 SMP_DBG("Local Public Key X: %32phN", smp->local_pk);
1779 SMP_DBG("Local Public Key Y: %32phN", &smp->local_pk[32]);
1780 SMP_DBG("Local Private Key: %32phN", smp->local_sk);
3b19146d
JH		 1781
1782 smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk);
1783
1784 return 0;
1785}
1786
da85e5e5 1787static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
88ba43b6 1788{
3158c50c 1789 struct smp_cmd_pairing *req, *rsp = (void *) skb->data;
5d88cc73
JH		 1790 struct l2cap_chan *chan = conn->smp;
1791 struct smp_chan *smp = chan->data;
0edb14de 1792 struct hci_dev *hdev = conn->hcon->hdev;
3a7dbfb8 1793 u8 key_size, auth;
7d24ddcc 1794 int ret;
88ba43b6
AB		 1795
1796 BT_DBG("conn %p", conn);
1797
c46b98be 1798 if (skb->len < sizeof(*rsp))
38e4a915 1799 return SMP_INVALID_PARAMS;
c46b98be 1800
40bef302 1801 if (conn->hcon->role != HCI_ROLE_MASTER)
2b64d153
BG		 1802 return SMP_CMD_NOTSUPP;
1803
3158c50c
VCG		 1804 skb_pull(skb, sizeof(*rsp));
1805
1c1def09 1806 req = (void *) &smp->preq[1];
da85e5e5 1807
3158c50c
VCG		 1808 key_size = min(req->max_key_size, rsp->max_key_size);
1809 if (check_enc_key_size(conn, key_size))
1810 return SMP_ENC_KEY_SIZE;
1811
0edb14de 1812 auth = rsp->auth_req & AUTH_REQ_MASK(hdev);
c05b9339 1813
903b71c7
JH		 1814 if (test_bit(HCI_SC_ONLY, &hdev->dev_flags) && !(auth & SMP_AUTH_SC))
1815 return SMP_AUTH_REQUIREMENTS;
1816
b5ae344d
JH		 1817 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1818 memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
1819
1820 /* Update remote key distribution in case the remote cleared
1821 * some bits that we had enabled in our request.
1822 */
1823 smp->remote_key_dist &= rsp->resp_key_dist;
1824
1825 /* For BR/EDR this means we're done and can start phase 3 */
1826 if (conn->hcon->type == ACL_LINK) {
1827 /* Clear bits which are generated but not distributed */
1828 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1829 smp_distribute_keys(smp);
1830 return 0;
1831 }
1832
65668776
JH		 1833 if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC))
1834 set_bit(SMP_FLAG_SC, &smp->flags);
d2eb9e10
JH		 1835 else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH)
1836 conn->hcon->pending_sec_level = BT_SECURITY_HIGH;
65668776 1837
49c922bb 1838 /* If we need MITM check that it can be achieved */
2ed8f65c
JH		 1839 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1840 u8 method;
1841
1842 method = get_auth_method(smp, req->io_capability,
1843 rsp->io_capability);
1844 if (method == JUST_WORKS || method == JUST_CFM)
1845 return SMP_AUTH_REQUIREMENTS;
1846 }
1847
e84a6b13 1848 get_random_bytes(smp->prnd, sizeof(smp->prnd));
7d24ddcc 1849
fdcc4bec
JH		 1850 /* Update remote key distribution in case the remote cleared
1851 * some bits that we had enabled in our request.
1852 */
1853 smp->remote_key_dist &= rsp->resp_key_dist;
1854
3b19146d
JH		 1855 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1856 /* Clear bits which are generated but not distributed */
1857 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1858 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
1859 return sc_send_public_key(smp);
1860 }
1861
c05b9339 1862 auth |= req->auth_req;
2b64d153 1863
476585ec 1864 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability);
2b64d153
BG		 1865 if (ret)
1866 return SMP_UNSPECIFIED;
1867
4a74d658 1868 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
2b64d153
BG		 1869
1870 /* Can't compose response until we have been confirmed */
4a74d658 1871 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
1cc61144 1872 return smp_confirm(smp);
da85e5e5
VCG		 1873
1874 return 0;
88ba43b6
AB		 1875}
1876
dcee2b32
JH		 1877static u8 sc_check_confirm(struct smp_chan *smp)
1878{
1879 struct l2cap_conn *conn = smp->conn;
1880
1881 BT_DBG("");
1882
1883 /* Public Key exchange must happen before any other steps */
1884 if (!test_bit(SMP_FLAG_REMOTE_PK, &smp->flags))
1885 return SMP_UNSPECIFIED;
1886
38606f14
JH		 1887 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
1888 return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM);
1889
dcee2b32
JH		 1890 if (conn->hcon->out) {
1891 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1892 smp->prnd);
1893 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1894 }
1895
1896 return 0;
1897}
1898
da85e5e5 1899static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
88ba43b6 1900{
5d88cc73
JH		 1901 struct l2cap_chan *chan = conn->smp;
1902 struct smp_chan *smp = chan->data;
7d24ddcc 1903
88ba43b6
AB		 1904 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
1905
c46b98be 1906 if (skb->len < sizeof(smp->pcnf))
38e4a915 1907 return SMP_INVALID_PARAMS;
c46b98be 1908
1c1def09
VCG		 1909 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
1910 skb_pull(skb, sizeof(smp->pcnf));
88ba43b6 1911
dcee2b32
JH		 1912 if (test_bit(SMP_FLAG_SC, &smp->flags))
1913 return sc_check_confirm(smp);
1914
b28b4943 1915 if (conn->hcon->out) {
943a732a
JH		 1916 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1917 smp->prnd);
b28b4943
JH		 1918 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1919 return 0;
1920 }
1921
1922 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
1cc61144 1923 return smp_confirm(smp);
943a732a 1924 else
4a74d658 1925 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
da85e5e5
VCG		 1926
1927 return 0;
88ba43b6
AB		 1928}
1929
da85e5e5 1930static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
88ba43b6 1931{
5d88cc73
JH		 1932 struct l2cap_chan *chan = conn->smp;
1933 struct smp_chan *smp = chan->data;
191dc7fe
JH		 1934 struct hci_conn *hcon = conn->hcon;
1935 u8 *pkax, *pkbx, *na, *nb;
1936 u32 passkey;
1937 int err;
7d24ddcc 1938
8aab4757 1939 BT_DBG("conn %p", conn);
3158c50c 1940
c46b98be 1941 if (skb->len < sizeof(smp->rrnd))
38e4a915 1942 return SMP_INVALID_PARAMS;
c46b98be 1943
943a732a 1944 memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd));
8aab4757 1945 skb_pull(skb, sizeof(smp->rrnd));
e7e62c85 1946
191dc7fe
JH		 1947 if (!test_bit(SMP_FLAG_SC, &smp->flags))
1948 return smp_random(smp);
1949
580039e8
JH		 1950 if (hcon->out) {
1951 pkax = smp->local_pk;
1952 pkbx = smp->remote_pk;
1953 na = smp->prnd;
1954 nb = smp->rrnd;
1955 } else {
1956 pkax = smp->remote_pk;
1957 pkbx = smp->local_pk;
1958 na = smp->rrnd;
1959 nb = smp->prnd;
1960 }
1961
a29b0733
JH		 1962 if (smp->method == REQ_OOB) {
1963 if (!hcon->out)
1964 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1965 sizeof(smp->prnd), smp->prnd);
1966 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1967 goto mackey_and_ltk;
1968 }
1969
38606f14
JH		 1970 /* Passkey entry has special treatment */
1971 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
1972 return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM);
1973
191dc7fe
JH		 1974 if (hcon->out) {
1975 u8 cfm[16];
1976
1977 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
1978 smp->rrnd, 0, cfm);
1979 if (err)
1980 return SMP_UNSPECIFIED;
1981
1982 if (memcmp(smp->pcnf, cfm, 16))
1983 return SMP_CONFIRM_FAILED;
191dc7fe
JH		 1984 } else {
1985 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1986 smp->prnd);
1987 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
191dc7fe
JH		 1988 }
1989
a29b0733 1990mackey_and_ltk:
760b018b
JH		 1991 /* Generate MacKey and LTK */
1992 err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk);
1993 if (err)
1994 return SMP_UNSPECIFIED;
1995
a29b0733 1996 if (smp->method == JUST_WORKS || smp->method == REQ_OOB) {
dddd3059 1997 if (hcon->out) {
38606f14 1998 sc_dhkey_check(smp);
dddd3059
JH		 1999 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2000 }
2001 return 0;
2002 }
2003
38606f14
JH		 2004 err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);
2005 if (err)
2006 return SMP_UNSPECIFIED;
2007
2008 err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type,
2009 hcon->dst_type, passkey, 0);
191dc7fe
JH		 2010 if (err)
2011 return SMP_UNSPECIFIED;
2012
38606f14
JH		 2013 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2014
191dc7fe 2015 return 0;
88ba43b6
AB		 2016}
2017
f81cd823 2018static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
988c5997 2019{
c9839a11 2020 struct smp_ltk *key;
988c5997
VCG		 2021 struct hci_conn *hcon = conn->hcon;
2022
f3a73d97 2023 key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role);
988c5997 2024 if (!key)
f81cd823 2025 return false;
988c5997 2026
a6f7833c 2027 if (smp_ltk_sec_level(key) < sec_level)
f81cd823 2028 return false;
4dab7864 2029
51a8efd7 2030 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
f81cd823 2031 return true;
988c5997 2032
c9839a11
VCG		 2033 hci_le_start_enc(hcon, key->ediv, key->rand, key->val);
2034 hcon->enc_key_size = key->enc_size;
988c5997 2035
fe59a05f
JH		 2036 /* We never store STKs for master role, so clear this flag */
2037 clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
2038
f81cd823 2039 return true;
988c5997 2040}
f1560463 2041
35dc6f83
JH		 2042bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level,
2043 enum smp_key_pref key_pref)
854f4727
JH		 2044{
2045 if (sec_level == BT_SECURITY_LOW)
2046 return true;
2047
35dc6f83
JH		 2048 /* If we're encrypted with an STK but the caller prefers using
2049 * LTK claim insufficient security. This way we allow the
2050 * connection to be re-encrypted with an LTK, even if the LTK
2051 * provides the same level of security. Only exception is if we
2052 * don't have an LTK (e.g. because of key distribution bits).
9ab65d60 2053 */
35dc6f83
JH		 2054 if (key_pref == SMP_USE_LTK &&
2055 test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) &&
f3a73d97 2056 hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role))
9ab65d60
JH		 2057 return false;
2058
854f4727
JH		 2059 if (hcon->sec_level >= sec_level)
2060 return true;
2061
2062 return false;
2063}
2064
da85e5e5 2065static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
88ba43b6
AB		 2066{
2067 struct smp_cmd_security_req *rp = (void *) skb->data;
2068 struct smp_cmd_pairing cp;
f1cb9af5 2069 struct hci_conn *hcon = conn->hcon;
0edb14de 2070 struct hci_dev *hdev = hcon->hdev;
8aab4757 2071 struct smp_chan *smp;
c05b9339 2072 u8 sec_level, auth;
88ba43b6
AB		 2073
2074 BT_DBG("conn %p", conn);
2075
c46b98be 2076 if (skb->len < sizeof(*rp))
38e4a915 2077 return SMP_INVALID_PARAMS;
c46b98be 2078
40bef302 2079 if (hcon->role != HCI_ROLE_MASTER)
86ca9eac
JH		 2080 return SMP_CMD_NOTSUPP;
2081
0edb14de 2082 auth = rp->auth_req & AUTH_REQ_MASK(hdev);
c05b9339 2083
903b71c7
JH		 2084 if (test_bit(HCI_SC_ONLY, &hdev->dev_flags) && !(auth & SMP_AUTH_SC))
2085 return SMP_AUTH_REQUIREMENTS;
2086
5be5e275 2087 if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
1afc2a1a
JH		 2088 sec_level = BT_SECURITY_MEDIUM;
2089 else
2090 sec_level = authreq_to_seclevel(auth);
2091
35dc6f83 2092 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
854f4727
JH		 2093 return 0;
2094
c7262e71
JH		 2095 if (sec_level > hcon->pending_sec_level)
2096 hcon->pending_sec_level = sec_level;
feb45eb5 2097
4dab7864 2098 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
988c5997
VCG		 2099 return 0;
2100
8aab4757 2101 smp = smp_chan_create(conn);
c29d2444
JH		 2102 if (!smp)
2103 return SMP_UNSPECIFIED;
d26a2345 2104
b6ae8457 2105 if (!test_bit(HCI_BONDABLE, &hcon->hdev->dev_flags) &&
c05b9339 2106 (auth & SMP_AUTH_BONDING))
616d55be
JH		 2107 return SMP_PAIRING_NOTSUPP;
2108
88ba43b6 2109 skb_pull(skb, sizeof(*rp));
88ba43b6 2110
da85e5e5 2111 memset(&cp, 0, sizeof(cp));
c05b9339 2112 build_pairing_cmd(conn, &cp, NULL, auth);
88ba43b6 2113
1c1def09
VCG		 2114 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2115 memcpy(&smp->preq[1], &cp, sizeof(cp));
f01ead31 2116
88ba43b6 2117 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
b28b4943 2118 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
f1cb9af5 2119
da85e5e5 2120 return 0;
88ba43b6
AB		 2121}
2122
cc110922 2123int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
eb492e01 2124{
cc110922 2125 struct l2cap_conn *conn = hcon->l2cap_data;
c68b7f12 2126 struct l2cap_chan *chan;
0a66cf20 2127 struct smp_chan *smp;
2b64d153 2128 __u8 authreq;
fc75cc86 2129 int ret;
eb492e01 2130
3a0259bb
VCG		 2131 BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);
2132
0a66cf20
JH		 2133 /* This may be NULL if there's an unexpected disconnection */
2134 if (!conn)
2135 return 1;
2136
c68b7f12
JH		 2137 chan = conn->smp;
2138
757aee0f 2139 if (!test_bit(HCI_LE_ENABLED, &hcon->hdev->dev_flags))
2e65c9d2
AG		 2140 return 1;
2141
35dc6f83 2142 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
eb492e01 2143 return 1;
f1cb9af5 2144
c7262e71
JH		 2145 if (sec_level > hcon->pending_sec_level)
2146 hcon->pending_sec_level = sec_level;
2147
40bef302 2148 if (hcon->role == HCI_ROLE_MASTER)
c7262e71
JH		 2149 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2150 return 0;
d26a2345 2151
fc75cc86
JH		 2152 l2cap_chan_lock(chan);
2153
2154 /* If SMP is already in progress ignore this request */
2155 if (chan->data) {
2156 ret = 0;
2157 goto unlock;
2158 }
d26a2345 2159
8aab4757 2160 smp = smp_chan_create(conn);
fc75cc86
JH		 2161 if (!smp) {
2162 ret = 1;
2163 goto unlock;
2164 }
2b64d153
BG		 2165
2166 authreq = seclevel_to_authreq(sec_level);
d26a2345 2167
d2eb9e10
JH		 2168 if (test_bit(HCI_SC_ENABLED, &hcon->hdev->dev_flags))
2169 authreq |= SMP_AUTH_SC;
2170
79897d20
JH		 2171 /* Require MITM if IO Capability allows or the security level
2172 * requires it.
2e233644 2173 */
79897d20 2174 if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT ||
c7262e71 2175 hcon->pending_sec_level > BT_SECURITY_MEDIUM)
2e233644
JH		 2176 authreq |= SMP_AUTH_MITM;
2177
40bef302 2178 if (hcon->role == HCI_ROLE_MASTER) {
d26a2345 2179 struct smp_cmd_pairing cp;
f01ead31 2180
2b64d153 2181 build_pairing_cmd(conn, &cp, NULL, authreq);
1c1def09
VCG		 2182 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2183 memcpy(&smp->preq[1], &cp, sizeof(cp));
f01ead31 2184
eb492e01 2185 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
b28b4943 2186 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
eb492e01
AB		 2187 } else {
2188 struct smp_cmd_security_req cp;
2b64d153 2189 cp.auth_req = authreq;
eb492e01 2190 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
b28b4943 2191 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ);
eb492e01
AB		 2192 }
2193
4a74d658 2194 set_bit(SMP_FLAG_INITIATOR, &smp->flags);
fc75cc86 2195 ret = 0;
edca792c 2196
fc75cc86
JH		 2197unlock:
2198 l2cap_chan_unlock(chan);
2199 return ret;
eb492e01
AB		 2200}
2201
7034b911
VCG		 2202static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb)
2203{
16b90839 2204 struct smp_cmd_encrypt_info *rp = (void *) skb->data;
5d88cc73
JH		 2205 struct l2cap_chan *chan = conn->smp;
2206 struct smp_chan *smp = chan->data;
16b90839 2207
c46b98be
JH		 2208 BT_DBG("conn %p", conn);
2209
2210 if (skb->len < sizeof(*rp))
38e4a915 2211 return SMP_INVALID_PARAMS;
c46b98be 2212
b28b4943 2213 SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT);
6131ddc8 2214
16b90839
VCG		 2215 skb_pull(skb, sizeof(*rp));
2216
1c1def09 2217 memcpy(smp->tk, rp->ltk, sizeof(smp->tk));
16b90839 2218
7034b911
VCG		 2219 return 0;
2220}
2221
2222static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
2223{
16b90839 2224 struct smp_cmd_master_ident *rp = (void *) skb->data;
5d88cc73
JH		 2225 struct l2cap_chan *chan = conn->smp;
2226 struct smp_chan *smp = chan->data;
c9839a11
VCG		 2227 struct hci_dev *hdev = conn->hcon->hdev;
2228 struct hci_conn *hcon = conn->hcon;
23d0e128 2229 struct smp_ltk *ltk;
c9839a11 2230 u8 authenticated;
16b90839 2231
c46b98be
JH		 2232 BT_DBG("conn %p", conn);
2233
2234 if (skb->len < sizeof(*rp))
38e4a915 2235 return SMP_INVALID_PARAMS;
c46b98be 2236
9747a9f3
JH		 2237 /* Mark the information as received */
2238 smp->remote_key_dist &= ~SMP_DIST_ENC_KEY;
2239
b28b4943
JH		 2240 if (smp->remote_key_dist & SMP_DIST_ID_KEY)
2241 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
196332f5
JH		 2242 else if (smp->remote_key_dist & SMP_DIST_SIGN)
2243 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
b28b4943 2244
16b90839 2245 skb_pull(skb, sizeof(*rp));
7034b911 2246
ce39fb4e 2247 authenticated = (hcon->sec_level == BT_SECURITY_HIGH);
2ceba539 2248 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK,
23d0e128
JH		 2249 authenticated, smp->tk, smp->enc_key_size,
2250 rp->ediv, rp->rand);
2251 smp->ltk = ltk;
c6e81e9a 2252 if (!(smp->remote_key_dist & KEY_DIST_MASK))
d6268e86 2253 smp_distribute_keys(smp);
7034b911
VCG		 2254
2255 return 0;
2256}
2257
fd349c02
JH		 2258static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb)
2259{
2260 struct smp_cmd_ident_info *info = (void *) skb->data;
5d88cc73
JH		 2261 struct l2cap_chan *chan = conn->smp;
2262 struct smp_chan *smp = chan->data;
fd349c02
JH		 2263
2264 BT_DBG("");
2265
2266 if (skb->len < sizeof(*info))
38e4a915 2267 return SMP_INVALID_PARAMS;
fd349c02 2268
b28b4943 2269 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO);
6131ddc8 2270
fd349c02
JH		 2271 skb_pull(skb, sizeof(*info));
2272
2273 memcpy(smp->irk, info->irk, 16);
2274
2275 return 0;
2276}
2277
2278static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,
2279 struct sk_buff *skb)
2280{
2281 struct smp_cmd_ident_addr_info *info = (void *) skb->data;
5d88cc73
JH		 2282 struct l2cap_chan *chan = conn->smp;
2283 struct smp_chan *smp = chan->data;
fd349c02
JH		 2284 struct hci_conn *hcon = conn->hcon;
2285 bdaddr_t rpa;
2286
2287 BT_DBG("");
2288
2289 if (skb->len < sizeof(*info))
38e4a915 2290 return SMP_INVALID_PARAMS;
fd349c02 2291
9747a9f3
JH		 2292 /* Mark the information as received */
2293 smp->remote_key_dist &= ~SMP_DIST_ID_KEY;
2294
b28b4943
JH		 2295 if (smp->remote_key_dist & SMP_DIST_SIGN)
2296 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2297
fd349c02
JH		 2298 skb_pull(skb, sizeof(*info));
2299
a9a58f86
JH		 2300 /* Strictly speaking the Core Specification (4.1) allows sending
2301 * an empty address which would force us to rely on just the IRK
2302 * as "identity information". However, since such
2303 * implementations are not known of and in order to not over
2304 * complicate our implementation, simply pretend that we never
2305 * received an IRK for such a device.
2306 */
2307 if (!bacmp(&info->bdaddr, BDADDR_ANY)) {
2308 BT_ERR("Ignoring IRK with no identity address");
31dd624e 2309 goto distribute;
a9a58f86
JH		 2310 }
2311
fd349c02
JH		 2312 bacpy(&smp->id_addr, &info->bdaddr);
2313 smp->id_addr_type = info->addr_type;
2314
2315 if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type))
2316 bacpy(&rpa, &hcon->dst);
2317 else
2318 bacpy(&rpa, BDADDR_ANY);
2319
23d0e128
JH		 2320 smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr,
2321 smp->id_addr_type, smp->irk, &rpa);
fd349c02 2322
31dd624e 2323distribute:
c6e81e9a
JH		 2324 if (!(smp->remote_key_dist & KEY_DIST_MASK))
2325 smp_distribute_keys(smp);
fd349c02
JH		 2326
2327 return 0;
2328}
2329
7ee4ea36
MH		 2330static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb)
2331{
2332 struct smp_cmd_sign_info *rp = (void *) skb->data;
5d88cc73
JH		 2333 struct l2cap_chan *chan = conn->smp;
2334 struct smp_chan *smp = chan->data;
7ee4ea36
MH		 2335 struct smp_csrk *csrk;
2336
2337 BT_DBG("conn %p", conn);
2338
2339 if (skb->len < sizeof(*rp))
38e4a915 2340 return SMP_INVALID_PARAMS;
7ee4ea36 2341
7ee4ea36
MH		 2342 /* Mark the information as received */
2343 smp->remote_key_dist &= ~SMP_DIST_SIGN;
2344
2345 skb_pull(skb, sizeof(*rp));
2346
7ee4ea36
MH		 2347 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
2348 if (csrk) {
2349 csrk->master = 0x01;
2350 memcpy(csrk->val, rp->csrk, sizeof(csrk->val));
2351 }
2352 smp->csrk = csrk;
d6268e86 2353 smp_distribute_keys(smp);
7ee4ea36
MH		 2354
2355 return 0;
2356}
2357
5e3d3d9b
JH		 2358static u8 sc_select_method(struct smp_chan *smp)
2359{
2360 struct l2cap_conn *conn = smp->conn;
2361 struct hci_conn *hcon = conn->hcon;
2362 struct smp_cmd_pairing *local, *remote;
2363 u8 local_mitm, remote_mitm, local_io, remote_io, method;
2364
a29b0733
JH		 2365 if (test_bit(SMP_FLAG_OOB, &smp->flags))
2366 return REQ_OOB;
2367
5e3d3d9b
JH		 2368 /* The preq/prsp contain the raw Pairing Request/Response PDUs
2369 * which are needed as inputs to some crypto functions. To get
2370 * the "struct smp_cmd_pairing" from them we need to skip the
2371 * first byte which contains the opcode.
2372 */
2373 if (hcon->out) {
2374 local = (void *) &smp->preq[1];
2375 remote = (void *) &smp->prsp[1];
2376 } else {
2377 local = (void *) &smp->prsp[1];
2378 remote = (void *) &smp->preq[1];
2379 }
2380
2381 local_io = local->io_capability;
2382 remote_io = remote->io_capability;
2383
2384 local_mitm = (local->auth_req & SMP_AUTH_MITM);
2385 remote_mitm = (remote->auth_req & SMP_AUTH_MITM);
2386
2387 /* If either side wants MITM, look up the method from the table,
2388 * otherwise use JUST WORKS.
2389 */
2390 if (local_mitm || remote_mitm)
2391 method = get_auth_method(smp, local_io, remote_io);
2392 else
2393 method = JUST_WORKS;
2394
2395 /* Don't confirm locally initiated pairing attempts */
2396 if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags))
2397 method = JUST_WORKS;
2398
2399 return method;
2400}
2401
d8f8edbe
JH		 2402static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb)
2403{
2404 struct smp_cmd_public_key *key = (void *) skb->data;
2405 struct hci_conn *hcon = conn->hcon;
2406 struct l2cap_chan *chan = conn->smp;
2407 struct smp_chan *smp = chan->data;
5e3d3d9b 2408 struct hci_dev *hdev = hcon->hdev;
cbbbe3e2 2409 struct smp_cmd_pairing_confirm cfm;
d8f8edbe
JH		 2410 int err;
2411
2412 BT_DBG("conn %p", conn);
2413
2414 if (skb->len < sizeof(*key))
2415 return SMP_INVALID_PARAMS;
2416
2417 memcpy(smp->remote_pk, key, 64);
2418
2419 /* Non-initiating device sends its public key after receiving
2420 * the key from the initiating device.
2421 */
2422 if (!hcon->out) {
2423 err = sc_send_public_key(smp);
2424 if (err)
2425 return err;
2426 }
2427
c7a3d57d
JH		 2428 SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk);
2429 SMP_DBG("Remote Public Key Y: %32phN", &smp->remote_pk[32]);
d8f8edbe
JH		 2430
2431 if (!ecdh_shared_secret(smp->remote_pk, smp->local_sk, smp->dhkey))
2432 return SMP_UNSPECIFIED;
2433
c7a3d57d 2434 SMP_DBG("DHKey %32phN", smp->dhkey);
d8f8edbe
JH		 2435
2436 set_bit(SMP_FLAG_REMOTE_PK, &smp->flags);
2437
5e3d3d9b
JH		 2438 smp->method = sc_select_method(smp);
2439
2440 BT_DBG("%s selected method 0x%02x", hdev->name, smp->method);
2441
2442 /* JUST_WORKS and JUST_CFM result in an unauthenticated key */
2443 if (smp->method == JUST_WORKS || smp->method == JUST_CFM)
2444 hcon->pending_sec_level = BT_SECURITY_MEDIUM;
2445 else
2446 hcon->pending_sec_level = BT_SECURITY_FIPS;
2447
aeb7d461
JH		 2448 if (!memcmp(debug_pk, smp->remote_pk, 64))
2449 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
2450
38606f14
JH		 2451 if (smp->method == DSP_PASSKEY) {
2452 get_random_bytes(&hcon->passkey_notify,
2453 sizeof(hcon->passkey_notify));
2454 hcon->passkey_notify %= 1000000;
2455 hcon->passkey_entered = 0;
2456 smp->passkey_round = 0;
2457 if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type,
2458 hcon->dst_type,
2459 hcon->passkey_notify,
2460 hcon->passkey_entered))
2461 return SMP_UNSPECIFIED;
2462 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2463 return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY);
2464 }
2465
a29b0733
JH		 2466 if (smp->method == REQ_OOB) {
2467 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk,
2468 smp->rr, 0, cfm.confirm_val);
2469 if (err)
2470 return SMP_UNSPECIFIED;
2471
2472 if (memcmp(cfm.confirm_val, smp->pcnf, 16))
2473 return SMP_CONFIRM_FAILED;
2474
2475 if (hcon->out)
2476 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2477 sizeof(smp->prnd), smp->prnd);
2478
2479 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2480
2481 return 0;
2482 }
2483
38606f14
JH		 2484 if (hcon->out)
2485 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2486
2487 if (smp->method == REQ_PASSKEY) {
2488 if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type,
2489 hcon->dst_type))
2490 return SMP_UNSPECIFIED;
2491 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2492 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2493 return 0;
2494 }
2495
cbbbe3e2
JH		 2496 /* The Initiating device waits for the non-initiating device to
2497 * send the confirm value.
2498 */
2499 if (conn->hcon->out)
2500 return 0;
2501
2502 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd,
2503 0, cfm.confirm_val);
2504 if (err)
2505 return SMP_UNSPECIFIED;
2506
2507 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
2508 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2509
d8f8edbe
JH		 2510 return 0;
2511}
2512
6433a9a2
JH		 2513static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb)
2514{
2515 struct smp_cmd_dhkey_check *check = (void *) skb->data;
2516 struct l2cap_chan *chan = conn->smp;
2517 struct hci_conn *hcon = conn->hcon;
2518 struct smp_chan *smp = chan->data;
2519 u8 a[7], b[7], *local_addr, *remote_addr;
2520 u8 io_cap[3], r[16], e[16];
2521 int err;
2522
2523 BT_DBG("conn %p", conn);
2524
2525 if (skb->len < sizeof(*check))
2526 return SMP_INVALID_PARAMS;
2527
2528 memcpy(a, &hcon->init_addr, 6);
2529 memcpy(b, &hcon->resp_addr, 6);
2530 a[6] = hcon->init_addr_type;
2531 b[6] = hcon->resp_addr_type;
2532
2533 if (hcon->out) {
2534 local_addr = a;
2535 remote_addr = b;
2536 memcpy(io_cap, &smp->prsp[1], 3);
2537 } else {
2538 local_addr = b;
2539 remote_addr = a;
2540 memcpy(io_cap, &smp->preq[1], 3);
2541 }
2542
2543 memset(r, 0, sizeof(r));
2544
38606f14
JH		 2545 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2546 put_unaligned_le32(hcon->passkey_notify, r);
2547
6433a9a2
JH		 2548 err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r,
2549 io_cap, remote_addr, local_addr, e);
2550 if (err)
2551 return SMP_UNSPECIFIED;
2552
2553 if (memcmp(check->e, e, 16))
2554 return SMP_DHKEY_CHECK_FAILED;
2555
d3e54a87
JH		 2556 if (!hcon->out) {
2557 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
2558 set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags);
2559 return 0;
2560 }
d378a2d7 2561
d3e54a87
JH		 2562 /* Slave sends DHKey check as response to master */
2563 sc_dhkey_check(smp);
2564 }
d378a2d7 2565
d3e54a87 2566 sc_add_ltk(smp);
6433a9a2
JH		 2567
2568 if (hcon->out) {
2569 hci_le_start_enc(hcon, 0, 0, smp->tk);
2570 hcon->enc_key_size = smp->enc_key_size;
2571 }
2572
2573 return 0;
2574}
2575
1408bb6e
JH		 2576static int smp_cmd_keypress_notify(struct l2cap_conn *conn,
2577 struct sk_buff *skb)
2578{
2579 struct smp_cmd_keypress_notify *kp = (void *) skb->data;
2580
2581 BT_DBG("value 0x%02x", kp->value);
2582
2583 return 0;
2584}
2585
4befb867 2586static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb)
eb492e01 2587{
5d88cc73 2588 struct l2cap_conn *conn = chan->conn;
7b9899db 2589 struct hci_conn *hcon = conn->hcon;
b28b4943 2590 struct smp_chan *smp;
92381f5c 2591 __u8 code, reason;
eb492e01
AB		 2592 int err = 0;
2593
8ae9b984 2594 if (skb->len < 1)
92381f5c 2595 return -EILSEQ;
92381f5c 2596
06ae3314 2597 if (!test_bit(HCI_LE_ENABLED, &hcon->hdev->dev_flags)) {
2e65c9d2
AG		 2598 reason = SMP_PAIRING_NOTSUPP;
2599 goto done;
2600 }
2601
92381f5c 2602 code = skb->data[0];
eb492e01
AB		 2603 skb_pull(skb, sizeof(code));
2604
b28b4943
JH		 2605 smp = chan->data;
2606
2607 if (code > SMP_CMD_MAX)
2608 goto drop;
2609
24bd0bd9 2610 if (smp && !test_and_clear_bit(code, &smp->allow_cmd))
b28b4943
JH		 2611 goto drop;
2612
2613 /* If we don't have a context the only allowed commands are
2614 * pairing request and security request.
8cf9fa12 2615 */
b28b4943
JH		 2616 if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ)
2617 goto drop;
8cf9fa12 2618
eb492e01
AB		 2619 switch (code) {
2620 case SMP_CMD_PAIRING_REQ:
da85e5e5 2621 reason = smp_cmd_pairing_req(conn, skb);
eb492e01
AB		 2622 break;
2623
2624 case SMP_CMD_PAIRING_FAIL:
84794e11 2625 smp_failure(conn, 0);
da85e5e5 2626 err = -EPERM;
eb492e01
AB		 2627 break;
2628
2629 case SMP_CMD_PAIRING_RSP:
da85e5e5 2630 reason = smp_cmd_pairing_rsp(conn, skb);
88ba43b6
AB		 2631 break;
2632
2633 case SMP_CMD_SECURITY_REQ:
da85e5e5 2634 reason = smp_cmd_security_req(conn, skb);
88ba43b6
AB		 2635 break;
2636
eb492e01 2637 case SMP_CMD_PAIRING_CONFIRM:
da85e5e5 2638 reason = smp_cmd_pairing_confirm(conn, skb);
88ba43b6
AB		 2639 break;
2640
eb492e01 2641 case SMP_CMD_PAIRING_RANDOM:
da85e5e5 2642 reason = smp_cmd_pairing_random(conn, skb);
88ba43b6
AB		 2643 break;
2644
eb492e01 2645 case SMP_CMD_ENCRYPT_INFO:
7034b911
VCG		 2646 reason = smp_cmd_encrypt_info(conn, skb);
2647 break;
2648
eb492e01 2649 case SMP_CMD_MASTER_IDENT:
7034b911
VCG		 2650 reason = smp_cmd_master_ident(conn, skb);
2651 break;
2652
eb492e01 2653 case SMP_CMD_IDENT_INFO:
fd349c02
JH		 2654 reason = smp_cmd_ident_info(conn, skb);
2655 break;
2656
eb492e01 2657 case SMP_CMD_IDENT_ADDR_INFO:
fd349c02
JH		 2658 reason = smp_cmd_ident_addr_info(conn, skb);
2659 break;
2660
eb492e01 2661 case SMP_CMD_SIGN_INFO:
7ee4ea36 2662 reason = smp_cmd_sign_info(conn, skb);
7034b911
VCG		 2663 break;
2664
d8f8edbe
JH		 2665 case SMP_CMD_PUBLIC_KEY:
2666 reason = smp_cmd_public_key(conn, skb);
2667 break;
2668
6433a9a2
JH		 2669 case SMP_CMD_DHKEY_CHECK:
2670 reason = smp_cmd_dhkey_check(conn, skb);
2671 break;
2672
1408bb6e
JH		 2673 case SMP_CMD_KEYPRESS_NOTIFY:
2674 reason = smp_cmd_keypress_notify(conn, skb);
2675 break;
2676
eb492e01
AB		 2677 default:
2678 BT_DBG("Unknown command code 0x%2.2x", code);
eb492e01 2679 reason = SMP_CMD_NOTSUPP;
3a0259bb 2680 goto done;
eb492e01
AB		 2681 }
2682
3a0259bb 2683done:
9b7b18ef
JH		 2684 if (!err) {
2685 if (reason)
2686 smp_failure(conn, reason);
8ae9b984 2687 kfree_skb(skb);
9b7b18ef
JH		 2688 }
2689
eb492e01 2690 return err;
b28b4943
JH		 2691
2692drop:
2693 BT_ERR("%s unexpected SMP command 0x%02x from %pMR", hcon->hdev->name,
2694 code, &hcon->dst);
2695 kfree_skb(skb);
2696 return 0;
eb492e01 2697}
7034b911 2698
70db83c4
JH		 2699static void smp_teardown_cb(struct l2cap_chan *chan, int err)
2700{
2701 struct l2cap_conn *conn = chan->conn;
2702
2703 BT_DBG("chan %p", chan);
2704
fc75cc86 2705 if (chan->data)
5d88cc73 2706 smp_chan_destroy(conn);
5d88cc73 2707
70db83c4
JH		 2708 conn->smp = NULL;
2709 l2cap_chan_put(chan);
2710}
2711
b5ae344d
JH		 2712static void bredr_pairing(struct l2cap_chan *chan)
2713{
2714 struct l2cap_conn *conn = chan->conn;
2715 struct hci_conn *hcon = conn->hcon;
2716 struct hci_dev *hdev = hcon->hdev;
2717 struct smp_cmd_pairing req;
2718 struct smp_chan *smp;
2719
2720 BT_DBG("chan %p", chan);
2721
2722 /* Only new pairings are interesting */
2723 if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags))
2724 return;
2725
2726 /* Don't bother if we're not encrypted */
2727 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
2728 return;
2729
2730 /* Only master may initiate SMP over BR/EDR */
2731 if (hcon->role != HCI_ROLE_MASTER)
2732 return;
2733
2734 /* Secure Connections support must be enabled */
2735 if (!test_bit(HCI_SC_ENABLED, &hdev->dev_flags))
2736 return;
2737
2738 /* BR/EDR must use Secure Connections for SMP */
2739 if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) &&
2740 !test_bit(HCI_FORCE_LESC, &hdev->dbg_flags))
2741 return;
2742
2743 /* If our LE support is not enabled don't do anything */
2744 if (!test_bit(HCI_LE_ENABLED, &hdev->dev_flags))
2745 return;
2746
2747 /* Don't bother if remote LE support is not enabled */
2748 if (!lmp_host_le_capable(hcon))
2749 return;
2750
2751 /* Remote must support SMP fixed chan for BR/EDR */
2752 if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR))
2753 return;
2754
2755 /* Don't bother if SMP is already ongoing */
2756 if (chan->data)
2757 return;
2758
2759 smp = smp_chan_create(conn);
2760 if (!smp) {
2761 BT_ERR("%s unable to create SMP context for BR/EDR",
2762 hdev->name);
2763 return;
2764 }
2765
2766 set_bit(SMP_FLAG_SC, &smp->flags);
2767
2768 BT_DBG("%s starting SMP over BR/EDR", hdev->name);
2769
2770 /* Prepare and send the BR/EDR SMP Pairing Request */
2771 build_bredr_pairing_cmd(smp, &req, NULL);
2772
2773 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2774 memcpy(&smp->preq[1], &req, sizeof(req));
2775
2776 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req);
2777 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2778}
2779
44f1a7ab
JH		 2780static void smp_resume_cb(struct l2cap_chan *chan)
2781{
b68fda68 2782 struct smp_chan *smp = chan->data;
44f1a7ab
JH		 2783 struct l2cap_conn *conn = chan->conn;
2784 struct hci_conn *hcon = conn->hcon;
2785
2786 BT_DBG("chan %p", chan);
2787
b5ae344d
JH		 2788 if (hcon->type == ACL_LINK) {
2789 bredr_pairing(chan);
ef8efe4b 2790 return;
b5ae344d 2791 }
ef8efe4b 2792
86d1407c
JH		 2793 if (!smp)
2794 return;
b68fda68 2795
84bc0db5
JH		 2796 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
2797 return;
2798
86d1407c
JH		 2799 cancel_delayed_work(&smp->security_timer);
2800
d6268e86 2801 smp_distribute_keys(smp);
44f1a7ab
JH		 2802}
2803
70db83c4
JH		 2804static void smp_ready_cb(struct l2cap_chan *chan)
2805{
2806 struct l2cap_conn *conn = chan->conn;
b5ae344d 2807 struct hci_conn *hcon = conn->hcon;
70db83c4
JH		 2808
2809 BT_DBG("chan %p", chan);
2810
2811 conn->smp = chan;
2812 l2cap_chan_hold(chan);
b5ae344d
JH		 2813
2814 if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
2815 bredr_pairing(chan);
70db83c4
JH		 2816}
2817
4befb867
JH		 2818static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
2819{
2820 int err;
2821
2822 BT_DBG("chan %p", chan);
2823
2824 err = smp_sig_channel(chan, skb);
2825 if (err) {
b68fda68 2826 struct smp_chan *smp = chan->data;
4befb867 2827
b68fda68
JH		 2828 if (smp)
2829 cancel_delayed_work_sync(&smp->security_timer);
4befb867 2830
1e91c29e 2831 hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE);
4befb867
JH		 2832 }
2833
2834 return err;
2835}
2836
70db83c4
JH		 2837static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan,
2838 unsigned long hdr_len,
2839 unsigned long len, int nb)
2840{
2841 struct sk_buff *skb;
2842
2843 skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL);
2844 if (!skb)
2845 return ERR_PTR(-ENOMEM);
2846
2847 skb->priority = HCI_PRIO_MAX;
2848 bt_cb(skb)->chan = chan;
2849
2850 return skb;
2851}
2852
2853static const struct l2cap_ops smp_chan_ops = {
2854 .name = "Security Manager",
2855 .ready = smp_ready_cb,
5d88cc73 2856 .recv = smp_recv_cb,
70db83c4
JH		 2857 .alloc_skb = smp_alloc_skb_cb,
2858 .teardown = smp_teardown_cb,
44f1a7ab 2859 .resume = smp_resume_cb,
70db83c4
JH		 2860
2861 .new_connection = l2cap_chan_no_new_connection,
70db83c4
JH		 2862 .state_change = l2cap_chan_no_state_change,
2863 .close = l2cap_chan_no_close,
2864 .defer = l2cap_chan_no_defer,
2865 .suspend = l2cap_chan_no_suspend,
70db83c4
JH		 2866 .set_shutdown = l2cap_chan_no_set_shutdown,
2867 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
70db83c4
JH		 2868};
2869
2870static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan)
2871{
2872 struct l2cap_chan *chan;
2873
2874 BT_DBG("pchan %p", pchan);
2875
2876 chan = l2cap_chan_create();
2877 if (!chan)
2878 return NULL;
2879
2880 chan->chan_type = pchan->chan_type;
2881 chan->ops = &smp_chan_ops;
2882 chan->scid = pchan->scid;
2883 chan->dcid = chan->scid;
2884 chan->imtu = pchan->imtu;
2885 chan->omtu = pchan->omtu;
2886 chan->mode = pchan->mode;
2887
abe84903
JH		 2888 /* Other L2CAP channels may request SMP routines in order to
2889 * change the security level. This means that the SMP channel
2890 * lock must be considered in its own category to avoid lockdep
2891 * warnings.
2892 */
2893 atomic_set(&chan->nesting, L2CAP_NESTING_SMP);
2894
70db83c4
JH		 2895 BT_DBG("created chan %p", chan);
2896
2897 return chan;
2898}
2899
2900static const struct l2cap_ops smp_root_chan_ops = {
2901 .name = "Security Manager Root",
2902 .new_connection = smp_new_conn_cb,
2903
2904 /* None of these are implemented for the root channel */
2905 .close = l2cap_chan_no_close,
2906 .alloc_skb = l2cap_chan_no_alloc_skb,
2907 .recv = l2cap_chan_no_recv,
2908 .state_change = l2cap_chan_no_state_change,
2909 .teardown = l2cap_chan_no_teardown,
2910 .ready = l2cap_chan_no_ready,
2911 .defer = l2cap_chan_no_defer,
2912 .suspend = l2cap_chan_no_suspend,
2913 .resume = l2cap_chan_no_resume,
2914 .set_shutdown = l2cap_chan_no_set_shutdown,
2915 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
70db83c4
JH		 2916};
2917
ef8efe4b 2918static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid)
711eafe3 2919{
70db83c4 2920 struct l2cap_chan *chan;
defce9e8 2921 struct crypto_blkcipher *tfm_aes;
70db83c4 2922
ef8efe4b
JH		 2923 if (cid == L2CAP_CID_SMP_BREDR) {
2924 tfm_aes = NULL;
2925 goto create_chan;
2926 }
711eafe3 2927
adae20cb 2928 tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, 0);
defce9e8 2929 if (IS_ERR(tfm_aes)) {
711eafe3 2930 BT_ERR("Unable to create crypto context");
fe700771 2931 return ERR_CAST(tfm_aes);
711eafe3
JH		 2932 }
2933
ef8efe4b 2934create_chan:
70db83c4
JH		 2935 chan = l2cap_chan_create();
2936 if (!chan) {
defce9e8 2937 crypto_free_blkcipher(tfm_aes);
ef8efe4b 2938 return ERR_PTR(-ENOMEM);
70db83c4
JH		 2939 }
2940
defce9e8
JH		 2941 chan->data = tfm_aes;
2942
ef8efe4b 2943 l2cap_add_scid(chan, cid);
70db83c4
JH		 2944
2945 l2cap_chan_set_defaults(chan);
2946
2947 bacpy(&chan->src, &hdev->bdaddr);
ef8efe4b
JH		 2948 if (cid == L2CAP_CID_SMP)
2949 chan->src_type = BDADDR_LE_PUBLIC;
2950 else
2951 chan->src_type = BDADDR_BREDR;
70db83c4
JH		 2952 chan->state = BT_LISTEN;
2953 chan->mode = L2CAP_MODE_BASIC;
2954 chan->imtu = L2CAP_DEFAULT_MTU;
2955 chan->ops = &smp_root_chan_ops;
2956
abe84903
JH		 2957 /* Set correct nesting level for a parent/listening channel */
2958 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
2959
ef8efe4b 2960 return chan;
711eafe3
JH		 2961}
2962
ef8efe4b 2963static void smp_del_chan(struct l2cap_chan *chan)
711eafe3 2964{
ef8efe4b 2965 struct crypto_blkcipher *tfm_aes;
70db83c4 2966
ef8efe4b 2967 BT_DBG("chan %p", chan);
711eafe3 2968
defce9e8
JH		 2969 tfm_aes = chan->data;
2970 if (tfm_aes) {
2971 chan->data = NULL;
2972 crypto_free_blkcipher(tfm_aes);
711eafe3 2973 }
70db83c4 2974
70db83c4 2975 l2cap_chan_put(chan);
711eafe3 2976}
ef8efe4b
JH		 2977
2978int smp_register(struct hci_dev *hdev)
2979{
2980 struct l2cap_chan *chan;
2981
2982 BT_DBG("%s", hdev->name);
2983
2984 chan = smp_add_cid(hdev, L2CAP_CID_SMP);
2985 if (IS_ERR(chan))
2986 return PTR_ERR(chan);
2987
2988 hdev->smp_data = chan;
2989
2990 if (!lmp_sc_capable(hdev) &&
2991 !test_bit(HCI_FORCE_LESC, &hdev->dbg_flags))
2992 return 0;
2993
2994 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
2995 if (IS_ERR(chan)) {
2996 int err = PTR_ERR(chan);
2997 chan = hdev->smp_data;
2998 hdev->smp_data = NULL;
2999 smp_del_chan(chan);
3000 return err;
3001 }
3002
3003 hdev->smp_bredr_data = chan;
3004
3005 return 0;
3006}
3007
3008void smp_unregister(struct hci_dev *hdev)
3009{
3010 struct l2cap_chan *chan;
3011
3012 if (hdev->smp_bredr_data) {
3013 chan = hdev->smp_bredr_data;
3014 hdev->smp_bredr_data = NULL;
3015 smp_del_chan(chan);
3016 }
3017
3018 if (hdev->smp_data) {
3019 chan = hdev->smp_data;
3020 hdev->smp_data = NULL;
3021 smp_del_chan(chan);
3022 }
3023}
Linux kernel - Deliverables
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