s390/bpf: reduce maximum program size to 64 KB
[linux/fpc-iii.git] / net / bluetooth / smp.c
blob50976a6481f3cd21e33e5ee75d74dacc06470584
1 /*
2 BlueZ - Bluetooth protocol stack for Linux
3 Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
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;
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.
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.
23 #include <linux/debugfs.h>
24 #include <linux/scatterlist.h>
25 #include <crypto/b128ops.h>
26 #include <crypto/hash.h>
27 #include <crypto/skcipher.h>
29 #include <net/bluetooth/bluetooth.h>
30 #include <net/bluetooth/hci_core.h>
31 #include <net/bluetooth/l2cap.h>
32 #include <net/bluetooth/mgmt.h>
34 #include "ecc.h"
35 #include "smp.h"
37 #define SMP_DEV(hdev) \
38 ((struct smp_dev *)((struct l2cap_chan *)((hdev)->smp_data))->data)
40 /* Low-level debug macros to be used for stuff that we don't want
41 * accidentially in dmesg, i.e. the values of the various crypto keys
42 * and the inputs & outputs of crypto functions.
44 #ifdef DEBUG
45 #define SMP_DBG(fmt, ...) printk(KERN_DEBUG "%s: " fmt, __func__, \
46 ##__VA_ARGS__)
47 #else
48 #define SMP_DBG(fmt, ...) no_printk(KERN_DEBUG "%s: " fmt, __func__, \
49 ##__VA_ARGS__)
50 #endif
52 #define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd)
54 /* Keys which are not distributed with Secure Connections */
55 #define SMP_SC_NO_DIST (SMP_DIST_ENC_KEY | SMP_DIST_LINK_KEY);
57 #define SMP_TIMEOUT msecs_to_jiffies(30000)
59 #define AUTH_REQ_MASK(dev) (hci_dev_test_flag(dev, HCI_SC_ENABLED) ? \
60 0x1f : 0x07)
61 #define KEY_DIST_MASK 0x07
63 /* Maximum message length that can be passed to aes_cmac */
64 #define CMAC_MSG_MAX 80
66 enum {
67 SMP_FLAG_TK_VALID,
68 SMP_FLAG_CFM_PENDING,
69 SMP_FLAG_MITM_AUTH,
70 SMP_FLAG_COMPLETE,
71 SMP_FLAG_INITIATOR,
72 SMP_FLAG_SC,
73 SMP_FLAG_REMOTE_PK,
74 SMP_FLAG_DEBUG_KEY,
75 SMP_FLAG_WAIT_USER,
76 SMP_FLAG_DHKEY_PENDING,
77 SMP_FLAG_REMOTE_OOB,
78 SMP_FLAG_LOCAL_OOB,
81 struct smp_dev {
82 /* Secure Connections OOB data */
83 u8 local_pk[64];
84 u8 local_sk[32];
85 u8 local_rand[16];
86 bool debug_key;
88 u8 min_key_size;
89 u8 max_key_size;
91 struct crypto_skcipher *tfm_aes;
92 struct crypto_shash *tfm_cmac;
95 struct smp_chan {
96 struct l2cap_conn *conn;
97 struct delayed_work security_timer;
98 unsigned long allow_cmd; /* Bitmask of allowed commands */
100 u8 preq[7]; /* SMP Pairing Request */
101 u8 prsp[7]; /* SMP Pairing Response */
102 u8 prnd[16]; /* SMP Pairing Random (local) */
103 u8 rrnd[16]; /* SMP Pairing Random (remote) */
104 u8 pcnf[16]; /* SMP Pairing Confirm */
105 u8 tk[16]; /* SMP Temporary Key */
106 u8 rr[16]; /* Remote OOB ra/rb value */
107 u8 lr[16]; /* Local OOB ra/rb value */
108 u8 enc_key_size;
109 u8 remote_key_dist;
110 bdaddr_t id_addr;
111 u8 id_addr_type;
112 u8 irk[16];
113 struct smp_csrk *csrk;
114 struct smp_csrk *slave_csrk;
115 struct smp_ltk *ltk;
116 struct smp_ltk *slave_ltk;
117 struct smp_irk *remote_irk;
118 u8 *link_key;
119 unsigned long flags;
120 u8 method;
121 u8 passkey_round;
123 /* Secure Connections variables */
124 u8 local_pk[64];
125 u8 local_sk[32];
126 u8 remote_pk[64];
127 u8 dhkey[32];
128 u8 mackey[16];
130 struct crypto_skcipher *tfm_aes;
131 struct crypto_shash *tfm_cmac;
134 /* These debug key values are defined in the SMP section of the core
135 * specification. debug_pk is the public debug key and debug_sk the
136 * private debug key.
138 static const u8 debug_pk[64] = {
139 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
140 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
141 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
142 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20,
144 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74,
145 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76,
146 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63,
147 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc,
150 static const u8 debug_sk[32] = {
151 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58,
152 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a,
153 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74,
154 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f,
157 static inline void swap_buf(const u8 *src, u8 *dst, size_t len)
159 size_t i;
161 for (i = 0; i < len; i++)
162 dst[len - 1 - i] = src[i];
165 /* The following functions map to the LE SC SMP crypto functions
166 * AES-CMAC, f4, f5, f6, g2 and h6.
169 static int aes_cmac(struct crypto_shash *tfm, const u8 k[16], const u8 *m,
170 size_t len, u8 mac[16])
172 uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX];
173 SHASH_DESC_ON_STACK(desc, tfm);
174 int err;
176 if (len > CMAC_MSG_MAX)
177 return -EFBIG;
179 if (!tfm) {
180 BT_ERR("tfm %p", tfm);
181 return -EINVAL;
184 desc->tfm = tfm;
185 desc->flags = 0;
187 /* Swap key and message from LSB to MSB */
188 swap_buf(k, tmp, 16);
189 swap_buf(m, msg_msb, len);
191 SMP_DBG("msg (len %zu) %*phN", len, (int) len, m);
192 SMP_DBG("key %16phN", k);
194 err = crypto_shash_setkey(tfm, tmp, 16);
195 if (err) {
196 BT_ERR("cipher setkey failed: %d", err);
197 return err;
200 err = crypto_shash_digest(desc, msg_msb, len, mac_msb);
201 shash_desc_zero(desc);
202 if (err) {
203 BT_ERR("Hash computation error %d", err);
204 return err;
207 swap_buf(mac_msb, mac, 16);
209 SMP_DBG("mac %16phN", mac);
211 return 0;
214 static int smp_f4(struct crypto_shash *tfm_cmac, const u8 u[32],
215 const u8 v[32], const u8 x[16], u8 z, u8 res[16])
217 u8 m[65];
218 int err;
220 SMP_DBG("u %32phN", u);
221 SMP_DBG("v %32phN", v);
222 SMP_DBG("x %16phN z %02x", x, z);
224 m[0] = z;
225 memcpy(m + 1, v, 32);
226 memcpy(m + 33, u, 32);
228 err = aes_cmac(tfm_cmac, x, m, sizeof(m), res);
229 if (err)
230 return err;
232 SMP_DBG("res %16phN", res);
234 return err;
237 static int smp_f5(struct crypto_shash *tfm_cmac, const u8 w[32],
238 const u8 n1[16], const u8 n2[16], const u8 a1[7],
239 const u8 a2[7], u8 mackey[16], u8 ltk[16])
241 /* The btle, salt and length "magic" values are as defined in
242 * the SMP section of the Bluetooth core specification. In ASCII
243 * the btle value ends up being 'btle'. The salt is just a
244 * random number whereas length is the value 256 in little
245 * endian format.
247 const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 };
248 const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60,
249 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c };
250 const u8 length[2] = { 0x00, 0x01 };
251 u8 m[53], t[16];
252 int err;
254 SMP_DBG("w %32phN", w);
255 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
256 SMP_DBG("a1 %7phN a2 %7phN", a1, a2);
258 err = aes_cmac(tfm_cmac, salt, w, 32, t);
259 if (err)
260 return err;
262 SMP_DBG("t %16phN", t);
264 memcpy(m, length, 2);
265 memcpy(m + 2, a2, 7);
266 memcpy(m + 9, a1, 7);
267 memcpy(m + 16, n2, 16);
268 memcpy(m + 32, n1, 16);
269 memcpy(m + 48, btle, 4);
271 m[52] = 0; /* Counter */
273 err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey);
274 if (err)
275 return err;
277 SMP_DBG("mackey %16phN", mackey);
279 m[52] = 1; /* Counter */
281 err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk);
282 if (err)
283 return err;
285 SMP_DBG("ltk %16phN", ltk);
287 return 0;
290 static int smp_f6(struct crypto_shash *tfm_cmac, const u8 w[16],
291 const u8 n1[16], const u8 n2[16], const u8 r[16],
292 const u8 io_cap[3], const u8 a1[7], const u8 a2[7],
293 u8 res[16])
295 u8 m[65];
296 int err;
298 SMP_DBG("w %16phN", w);
299 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
300 SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2);
302 memcpy(m, a2, 7);
303 memcpy(m + 7, a1, 7);
304 memcpy(m + 14, io_cap, 3);
305 memcpy(m + 17, r, 16);
306 memcpy(m + 33, n2, 16);
307 memcpy(m + 49, n1, 16);
309 err = aes_cmac(tfm_cmac, w, m, sizeof(m), res);
310 if (err)
311 return err;
313 SMP_DBG("res %16phN", res);
315 return err;
318 static int smp_g2(struct crypto_shash *tfm_cmac, const u8 u[32], const u8 v[32],
319 const u8 x[16], const u8 y[16], u32 *val)
321 u8 m[80], tmp[16];
322 int err;
324 SMP_DBG("u %32phN", u);
325 SMP_DBG("v %32phN", v);
326 SMP_DBG("x %16phN y %16phN", x, y);
328 memcpy(m, y, 16);
329 memcpy(m + 16, v, 32);
330 memcpy(m + 48, u, 32);
332 err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp);
333 if (err)
334 return err;
336 *val = get_unaligned_le32(tmp);
337 *val %= 1000000;
339 SMP_DBG("val %06u", *val);
341 return 0;
344 static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16],
345 const u8 key_id[4], u8 res[16])
347 int err;
349 SMP_DBG("w %16phN key_id %4phN", w, key_id);
351 err = aes_cmac(tfm_cmac, w, key_id, 4, res);
352 if (err)
353 return err;
355 SMP_DBG("res %16phN", res);
357 return err;
360 /* The following functions map to the legacy SMP crypto functions e, c1,
361 * s1 and ah.
364 static int smp_e(struct crypto_skcipher *tfm, const u8 *k, u8 *r)
366 SKCIPHER_REQUEST_ON_STACK(req, tfm);
367 struct scatterlist sg;
368 uint8_t tmp[16], data[16];
369 int err;
371 SMP_DBG("k %16phN r %16phN", k, r);
373 if (!tfm) {
374 BT_ERR("tfm %p", tfm);
375 return -EINVAL;
378 /* The most significant octet of key corresponds to k[0] */
379 swap_buf(k, tmp, 16);
381 err = crypto_skcipher_setkey(tfm, tmp, 16);
382 if (err) {
383 BT_ERR("cipher setkey failed: %d", err);
384 return err;
387 /* Most significant octet of plaintextData corresponds to data[0] */
388 swap_buf(r, data, 16);
390 sg_init_one(&sg, data, 16);
392 skcipher_request_set_tfm(req, tfm);
393 skcipher_request_set_callback(req, 0, NULL, NULL);
394 skcipher_request_set_crypt(req, &sg, &sg, 16, NULL);
396 err = crypto_skcipher_encrypt(req);
397 skcipher_request_zero(req);
398 if (err)
399 BT_ERR("Encrypt data error %d", err);
401 /* Most significant octet of encryptedData corresponds to data[0] */
402 swap_buf(data, r, 16);
404 SMP_DBG("r %16phN", r);
406 return err;
409 static int smp_c1(struct crypto_skcipher *tfm_aes, const u8 k[16],
410 const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat,
411 const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16])
413 u8 p1[16], p2[16];
414 int err;
416 SMP_DBG("k %16phN r %16phN", k, r);
417 SMP_DBG("iat %u ia %6phN rat %u ra %6phN", _iat, ia, _rat, ra);
418 SMP_DBG("preq %7phN pres %7phN", preq, pres);
420 memset(p1, 0, 16);
422 /* p1 = pres || preq || _rat || _iat */
423 p1[0] = _iat;
424 p1[1] = _rat;
425 memcpy(p1 + 2, preq, 7);
426 memcpy(p1 + 9, pres, 7);
428 SMP_DBG("p1 %16phN", p1);
430 /* res = r XOR p1 */
431 u128_xor((u128 *) res, (u128 *) r, (u128 *) p1);
433 /* res = e(k, res) */
434 err = smp_e(tfm_aes, k, res);
435 if (err) {
436 BT_ERR("Encrypt data error");
437 return err;
440 /* p2 = padding || ia || ra */
441 memcpy(p2, ra, 6);
442 memcpy(p2 + 6, ia, 6);
443 memset(p2 + 12, 0, 4);
445 SMP_DBG("p2 %16phN", p2);
447 /* res = res XOR p2 */
448 u128_xor((u128 *) res, (u128 *) res, (u128 *) p2);
450 /* res = e(k, res) */
451 err = smp_e(tfm_aes, k, res);
452 if (err)
453 BT_ERR("Encrypt data error");
455 return err;
458 static int smp_s1(struct crypto_skcipher *tfm_aes, const u8 k[16],
459 const u8 r1[16], const u8 r2[16], u8 _r[16])
461 int err;
463 /* Just least significant octets from r1 and r2 are considered */
464 memcpy(_r, r2, 8);
465 memcpy(_r + 8, r1, 8);
467 err = smp_e(tfm_aes, k, _r);
468 if (err)
469 BT_ERR("Encrypt data error");
471 return err;
474 static int smp_ah(struct crypto_skcipher *tfm, const u8 irk[16],
475 const u8 r[3], u8 res[3])
477 u8 _res[16];
478 int err;
480 /* r' = padding || r */
481 memcpy(_res, r, 3);
482 memset(_res + 3, 0, 13);
484 err = smp_e(tfm, irk, _res);
485 if (err) {
486 BT_ERR("Encrypt error");
487 return err;
490 /* The output of the random address function ah is:
491 * ah(k, r) = e(k, r') mod 2^24
492 * The output of the security function e is then truncated to 24 bits
493 * by taking the least significant 24 bits of the output of e as the
494 * result of ah.
496 memcpy(res, _res, 3);
498 return 0;
501 bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16],
502 const bdaddr_t *bdaddr)
504 struct l2cap_chan *chan = hdev->smp_data;
505 struct smp_dev *smp;
506 u8 hash[3];
507 int err;
509 if (!chan || !chan->data)
510 return false;
512 smp = chan->data;
514 BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk);
516 err = smp_ah(smp->tfm_aes, irk, &bdaddr->b[3], hash);
517 if (err)
518 return false;
520 return !memcmp(bdaddr->b, hash, 3);
523 int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa)
525 struct l2cap_chan *chan = hdev->smp_data;
526 struct smp_dev *smp;
527 int err;
529 if (!chan || !chan->data)
530 return -EOPNOTSUPP;
532 smp = chan->data;
534 get_random_bytes(&rpa->b[3], 3);
536 rpa->b[5] &= 0x3f; /* Clear two most significant bits */
537 rpa->b[5] |= 0x40; /* Set second most significant bit */
539 err = smp_ah(smp->tfm_aes, irk, &rpa->b[3], rpa->b);
540 if (err < 0)
541 return err;
543 BT_DBG("RPA %pMR", rpa);
545 return 0;
548 int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16])
550 struct l2cap_chan *chan = hdev->smp_data;
551 struct smp_dev *smp;
552 int err;
554 if (!chan || !chan->data)
555 return -EOPNOTSUPP;
557 smp = chan->data;
559 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
560 BT_DBG("Using debug keys");
561 memcpy(smp->local_pk, debug_pk, 64);
562 memcpy(smp->local_sk, debug_sk, 32);
563 smp->debug_key = true;
564 } else {
565 while (true) {
566 /* Generate local key pair for Secure Connections */
567 if (!ecc_make_key(smp->local_pk, smp->local_sk))
568 return -EIO;
570 /* This is unlikely, but we need to check that
571 * we didn't accidentially generate a debug key.
573 if (memcmp(smp->local_sk, debug_sk, 32))
574 break;
576 smp->debug_key = false;
579 SMP_DBG("OOB Public Key X: %32phN", smp->local_pk);
580 SMP_DBG("OOB Public Key Y: %32phN", smp->local_pk + 32);
581 SMP_DBG("OOB Private Key: %32phN", smp->local_sk);
583 get_random_bytes(smp->local_rand, 16);
585 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->local_pk,
586 smp->local_rand, 0, hash);
587 if (err < 0)
588 return err;
590 memcpy(rand, smp->local_rand, 16);
592 return 0;
595 static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
597 struct l2cap_chan *chan = conn->smp;
598 struct smp_chan *smp;
599 struct kvec iv[2];
600 struct msghdr msg;
602 if (!chan)
603 return;
605 BT_DBG("code 0x%2.2x", code);
607 iv[0].iov_base = &code;
608 iv[0].iov_len = 1;
610 iv[1].iov_base = data;
611 iv[1].iov_len = len;
613 memset(&msg, 0, sizeof(msg));
615 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iv, 2, 1 + len);
617 l2cap_chan_send(chan, &msg, 1 + len);
619 if (!chan->data)
620 return;
622 smp = chan->data;
624 cancel_delayed_work_sync(&smp->security_timer);
625 schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT);
628 static u8 authreq_to_seclevel(u8 authreq)
630 if (authreq & SMP_AUTH_MITM) {
631 if (authreq & SMP_AUTH_SC)
632 return BT_SECURITY_FIPS;
633 else
634 return BT_SECURITY_HIGH;
635 } else {
636 return BT_SECURITY_MEDIUM;
640 static __u8 seclevel_to_authreq(__u8 sec_level)
642 switch (sec_level) {
643 case BT_SECURITY_FIPS:
644 case BT_SECURITY_HIGH:
645 return SMP_AUTH_MITM | SMP_AUTH_BONDING;
646 case BT_SECURITY_MEDIUM:
647 return SMP_AUTH_BONDING;
648 default:
649 return SMP_AUTH_NONE;
653 static void build_pairing_cmd(struct l2cap_conn *conn,
654 struct smp_cmd_pairing *req,
655 struct smp_cmd_pairing *rsp, __u8 authreq)
657 struct l2cap_chan *chan = conn->smp;
658 struct smp_chan *smp = chan->data;
659 struct hci_conn *hcon = conn->hcon;
660 struct hci_dev *hdev = hcon->hdev;
661 u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT;
663 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
664 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
665 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
666 authreq |= SMP_AUTH_BONDING;
667 } else {
668 authreq &= ~SMP_AUTH_BONDING;
671 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
672 remote_dist |= SMP_DIST_ID_KEY;
674 if (hci_dev_test_flag(hdev, HCI_PRIVACY))
675 local_dist |= SMP_DIST_ID_KEY;
677 if (hci_dev_test_flag(hdev, HCI_SC_ENABLED) &&
678 (authreq & SMP_AUTH_SC)) {
679 struct oob_data *oob_data;
680 u8 bdaddr_type;
682 if (hci_dev_test_flag(hdev, HCI_SSP_ENABLED)) {
683 local_dist |= SMP_DIST_LINK_KEY;
684 remote_dist |= SMP_DIST_LINK_KEY;
687 if (hcon->dst_type == ADDR_LE_DEV_PUBLIC)
688 bdaddr_type = BDADDR_LE_PUBLIC;
689 else
690 bdaddr_type = BDADDR_LE_RANDOM;
692 oob_data = hci_find_remote_oob_data(hdev, &hcon->dst,
693 bdaddr_type);
694 if (oob_data && oob_data->present) {
695 set_bit(SMP_FLAG_REMOTE_OOB, &smp->flags);
696 oob_flag = SMP_OOB_PRESENT;
697 memcpy(smp->rr, oob_data->rand256, 16);
698 memcpy(smp->pcnf, oob_data->hash256, 16);
699 SMP_DBG("OOB Remote Confirmation: %16phN", smp->pcnf);
700 SMP_DBG("OOB Remote Random: %16phN", smp->rr);
703 } else {
704 authreq &= ~SMP_AUTH_SC;
707 if (rsp == NULL) {
708 req->io_capability = conn->hcon->io_capability;
709 req->oob_flag = oob_flag;
710 req->max_key_size = SMP_DEV(hdev)->max_key_size;
711 req->init_key_dist = local_dist;
712 req->resp_key_dist = remote_dist;
713 req->auth_req = (authreq & AUTH_REQ_MASK(hdev));
715 smp->remote_key_dist = remote_dist;
716 return;
719 rsp->io_capability = conn->hcon->io_capability;
720 rsp->oob_flag = oob_flag;
721 rsp->max_key_size = SMP_DEV(hdev)->max_key_size;
722 rsp->init_key_dist = req->init_key_dist & remote_dist;
723 rsp->resp_key_dist = req->resp_key_dist & local_dist;
724 rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev));
726 smp->remote_key_dist = rsp->init_key_dist;
729 static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)
731 struct l2cap_chan *chan = conn->smp;
732 struct hci_dev *hdev = conn->hcon->hdev;
733 struct smp_chan *smp = chan->data;
735 if (max_key_size > SMP_DEV(hdev)->max_key_size ||
736 max_key_size < SMP_MIN_ENC_KEY_SIZE)
737 return SMP_ENC_KEY_SIZE;
739 smp->enc_key_size = max_key_size;
741 return 0;
744 static void smp_chan_destroy(struct l2cap_conn *conn)
746 struct l2cap_chan *chan = conn->smp;
747 struct smp_chan *smp = chan->data;
748 struct hci_conn *hcon = conn->hcon;
749 bool complete;
751 BUG_ON(!smp);
753 cancel_delayed_work_sync(&smp->security_timer);
755 complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags);
756 mgmt_smp_complete(hcon, complete);
758 kzfree(smp->csrk);
759 kzfree(smp->slave_csrk);
760 kzfree(smp->link_key);
762 crypto_free_skcipher(smp->tfm_aes);
763 crypto_free_shash(smp->tfm_cmac);
765 /* Ensure that we don't leave any debug key around if debug key
766 * support hasn't been explicitly enabled.
768 if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG &&
769 !hci_dev_test_flag(hcon->hdev, HCI_KEEP_DEBUG_KEYS)) {
770 list_del_rcu(&smp->ltk->list);
771 kfree_rcu(smp->ltk, rcu);
772 smp->ltk = NULL;
775 /* If pairing failed clean up any keys we might have */
776 if (!complete) {
777 if (smp->ltk) {
778 list_del_rcu(&smp->ltk->list);
779 kfree_rcu(smp->ltk, rcu);
782 if (smp->slave_ltk) {
783 list_del_rcu(&smp->slave_ltk->list);
784 kfree_rcu(smp->slave_ltk, rcu);
787 if (smp->remote_irk) {
788 list_del_rcu(&smp->remote_irk->list);
789 kfree_rcu(smp->remote_irk, rcu);
793 chan->data = NULL;
794 kzfree(smp);
795 hci_conn_drop(hcon);
798 static void smp_failure(struct l2cap_conn *conn, u8 reason)
800 struct hci_conn *hcon = conn->hcon;
801 struct l2cap_chan *chan = conn->smp;
803 if (reason)
804 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
805 &reason);
807 mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE);
809 if (chan->data)
810 smp_chan_destroy(conn);
813 #define JUST_WORKS 0x00
814 #define JUST_CFM 0x01
815 #define REQ_PASSKEY 0x02
816 #define CFM_PASSKEY 0x03
817 #define REQ_OOB 0x04
818 #define DSP_PASSKEY 0x05
819 #define OVERLAP 0xFF
821 static const u8 gen_method[5][5] = {
822 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
823 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
824 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
825 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
826 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP },
829 static const u8 sc_method[5][5] = {
830 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
831 { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
832 { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY },
833 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
834 { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
837 static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io)
839 /* If either side has unknown io_caps, use JUST_CFM (which gets
840 * converted later to JUST_WORKS if we're initiators.
842 if (local_io > SMP_IO_KEYBOARD_DISPLAY ||
843 remote_io > SMP_IO_KEYBOARD_DISPLAY)
844 return JUST_CFM;
846 if (test_bit(SMP_FLAG_SC, &smp->flags))
847 return sc_method[remote_io][local_io];
849 return gen_method[remote_io][local_io];
852 static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
853 u8 local_io, u8 remote_io)
855 struct hci_conn *hcon = conn->hcon;
856 struct l2cap_chan *chan = conn->smp;
857 struct smp_chan *smp = chan->data;
858 u32 passkey = 0;
859 int ret = 0;
861 /* Initialize key for JUST WORKS */
862 memset(smp->tk, 0, sizeof(smp->tk));
863 clear_bit(SMP_FLAG_TK_VALID, &smp->flags);
865 BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io);
867 /* If neither side wants MITM, either "just" confirm an incoming
868 * request or use just-works for outgoing ones. The JUST_CFM
869 * will be converted to JUST_WORKS if necessary later in this
870 * function. If either side has MITM look up the method from the
871 * table.
873 if (!(auth & SMP_AUTH_MITM))
874 smp->method = JUST_CFM;
875 else
876 smp->method = get_auth_method(smp, local_io, remote_io);
878 /* Don't confirm locally initiated pairing attempts */
879 if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR,
880 &smp->flags))
881 smp->method = JUST_WORKS;
883 /* Don't bother user space with no IO capabilities */
884 if (smp->method == JUST_CFM &&
885 hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
886 smp->method = JUST_WORKS;
888 /* If Just Works, Continue with Zero TK */
889 if (smp->method == JUST_WORKS) {
890 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
891 return 0;
894 /* If this function is used for SC -> legacy fallback we
895 * can only recover the just-works case.
897 if (test_bit(SMP_FLAG_SC, &smp->flags))
898 return -EINVAL;
900 /* Not Just Works/Confirm results in MITM Authentication */
901 if (smp->method != JUST_CFM) {
902 set_bit(SMP_FLAG_MITM_AUTH, &smp->flags);
903 if (hcon->pending_sec_level < BT_SECURITY_HIGH)
904 hcon->pending_sec_level = BT_SECURITY_HIGH;
907 /* If both devices have Keyoard-Display I/O, the master
908 * Confirms and the slave Enters the passkey.
910 if (smp->method == OVERLAP) {
911 if (hcon->role == HCI_ROLE_MASTER)
912 smp->method = CFM_PASSKEY;
913 else
914 smp->method = REQ_PASSKEY;
917 /* Generate random passkey. */
918 if (smp->method == CFM_PASSKEY) {
919 memset(smp->tk, 0, sizeof(smp->tk));
920 get_random_bytes(&passkey, sizeof(passkey));
921 passkey %= 1000000;
922 put_unaligned_le32(passkey, smp->tk);
923 BT_DBG("PassKey: %d", passkey);
924 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
927 if (smp->method == REQ_PASSKEY)
928 ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst,
929 hcon->type, hcon->dst_type);
930 else if (smp->method == JUST_CFM)
931 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
932 hcon->type, hcon->dst_type,
933 passkey, 1);
934 else
935 ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst,
936 hcon->type, hcon->dst_type,
937 passkey, 0);
939 return ret;
942 static u8 smp_confirm(struct smp_chan *smp)
944 struct l2cap_conn *conn = smp->conn;
945 struct smp_cmd_pairing_confirm cp;
946 int ret;
948 BT_DBG("conn %p", conn);
950 ret = smp_c1(smp->tfm_aes, smp->tk, smp->prnd, smp->preq, smp->prsp,
951 conn->hcon->init_addr_type, &conn->hcon->init_addr,
952 conn->hcon->resp_addr_type, &conn->hcon->resp_addr,
953 cp.confirm_val);
954 if (ret)
955 return SMP_UNSPECIFIED;
957 clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
959 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
961 if (conn->hcon->out)
962 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
963 else
964 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
966 return 0;
969 static u8 smp_random(struct smp_chan *smp)
971 struct l2cap_conn *conn = smp->conn;
972 struct hci_conn *hcon = conn->hcon;
973 u8 confirm[16];
974 int ret;
976 if (IS_ERR_OR_NULL(smp->tfm_aes))
977 return SMP_UNSPECIFIED;
979 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
981 ret = smp_c1(smp->tfm_aes, smp->tk, smp->rrnd, smp->preq, smp->prsp,
982 hcon->init_addr_type, &hcon->init_addr,
983 hcon->resp_addr_type, &hcon->resp_addr, confirm);
984 if (ret)
985 return SMP_UNSPECIFIED;
987 if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) {
988 BT_ERR("Pairing failed (confirmation values mismatch)");
989 return SMP_CONFIRM_FAILED;
992 if (hcon->out) {
993 u8 stk[16];
994 __le64 rand = 0;
995 __le16 ediv = 0;
997 smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk);
999 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
1000 return SMP_UNSPECIFIED;
1002 hci_le_start_enc(hcon, ediv, rand, stk, smp->enc_key_size);
1003 hcon->enc_key_size = smp->enc_key_size;
1004 set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
1005 } else {
1006 u8 stk[16], auth;
1007 __le64 rand = 0;
1008 __le16 ediv = 0;
1010 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1011 smp->prnd);
1013 smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk);
1015 if (hcon->pending_sec_level == BT_SECURITY_HIGH)
1016 auth = 1;
1017 else
1018 auth = 0;
1020 /* Even though there's no _SLAVE suffix this is the
1021 * slave STK we're adding for later lookup (the master
1022 * STK never needs to be stored).
1024 hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1025 SMP_STK, auth, stk, smp->enc_key_size, ediv, rand);
1028 return 0;
1031 static void smp_notify_keys(struct l2cap_conn *conn)
1033 struct l2cap_chan *chan = conn->smp;
1034 struct smp_chan *smp = chan->data;
1035 struct hci_conn *hcon = conn->hcon;
1036 struct hci_dev *hdev = hcon->hdev;
1037 struct smp_cmd_pairing *req = (void *) &smp->preq[1];
1038 struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1];
1039 bool persistent;
1041 if (hcon->type == ACL_LINK) {
1042 if (hcon->key_type == HCI_LK_DEBUG_COMBINATION)
1043 persistent = false;
1044 else
1045 persistent = !test_bit(HCI_CONN_FLUSH_KEY,
1046 &hcon->flags);
1047 } else {
1048 /* The LTKs, IRKs and CSRKs should be persistent only if
1049 * both sides had the bonding bit set in their
1050 * authentication requests.
1052 persistent = !!((req->auth_req & rsp->auth_req) &
1053 SMP_AUTH_BONDING);
1056 if (smp->remote_irk) {
1057 mgmt_new_irk(hdev, smp->remote_irk, persistent);
1059 /* Now that user space can be considered to know the
1060 * identity address track the connection based on it
1061 * from now on (assuming this is an LE link).
1063 if (hcon->type == LE_LINK) {
1064 bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
1065 hcon->dst_type = smp->remote_irk->addr_type;
1066 queue_work(hdev->workqueue, &conn->id_addr_update_work);
1070 if (smp->csrk) {
1071 smp->csrk->bdaddr_type = hcon->dst_type;
1072 bacpy(&smp->csrk->bdaddr, &hcon->dst);
1073 mgmt_new_csrk(hdev, smp->csrk, persistent);
1076 if (smp->slave_csrk) {
1077 smp->slave_csrk->bdaddr_type = hcon->dst_type;
1078 bacpy(&smp->slave_csrk->bdaddr, &hcon->dst);
1079 mgmt_new_csrk(hdev, smp->slave_csrk, persistent);
1082 if (smp->ltk) {
1083 smp->ltk->bdaddr_type = hcon->dst_type;
1084 bacpy(&smp->ltk->bdaddr, &hcon->dst);
1085 mgmt_new_ltk(hdev, smp->ltk, persistent);
1088 if (smp->slave_ltk) {
1089 smp->slave_ltk->bdaddr_type = hcon->dst_type;
1090 bacpy(&smp->slave_ltk->bdaddr, &hcon->dst);
1091 mgmt_new_ltk(hdev, smp->slave_ltk, persistent);
1094 if (smp->link_key) {
1095 struct link_key *key;
1096 u8 type;
1098 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1099 type = HCI_LK_DEBUG_COMBINATION;
1100 else if (hcon->sec_level == BT_SECURITY_FIPS)
1101 type = HCI_LK_AUTH_COMBINATION_P256;
1102 else
1103 type = HCI_LK_UNAUTH_COMBINATION_P256;
1105 key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst,
1106 smp->link_key, type, 0, &persistent);
1107 if (key) {
1108 mgmt_new_link_key(hdev, key, persistent);
1110 /* Don't keep debug keys around if the relevant
1111 * flag is not set.
1113 if (!hci_dev_test_flag(hdev, HCI_KEEP_DEBUG_KEYS) &&
1114 key->type == HCI_LK_DEBUG_COMBINATION) {
1115 list_del_rcu(&key->list);
1116 kfree_rcu(key, rcu);
1122 static void sc_add_ltk(struct smp_chan *smp)
1124 struct hci_conn *hcon = smp->conn->hcon;
1125 u8 key_type, auth;
1127 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1128 key_type = SMP_LTK_P256_DEBUG;
1129 else
1130 key_type = SMP_LTK_P256;
1132 if (hcon->pending_sec_level == BT_SECURITY_FIPS)
1133 auth = 1;
1134 else
1135 auth = 0;
1137 smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1138 key_type, auth, smp->tk, smp->enc_key_size,
1139 0, 0);
1142 static void sc_generate_link_key(struct smp_chan *smp)
1144 /* These constants are as specified in the core specification.
1145 * In ASCII they spell out to 'tmp1' and 'lebr'.
1147 const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 };
1148 const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c };
1150 smp->link_key = kzalloc(16, GFP_KERNEL);
1151 if (!smp->link_key)
1152 return;
1154 if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) {
1155 kzfree(smp->link_key);
1156 smp->link_key = NULL;
1157 return;
1160 if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) {
1161 kzfree(smp->link_key);
1162 smp->link_key = NULL;
1163 return;
1167 static void smp_allow_key_dist(struct smp_chan *smp)
1169 /* Allow the first expected phase 3 PDU. The rest of the PDUs
1170 * will be allowed in each PDU handler to ensure we receive
1171 * them in the correct order.
1173 if (smp->remote_key_dist & SMP_DIST_ENC_KEY)
1174 SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO);
1175 else if (smp->remote_key_dist & SMP_DIST_ID_KEY)
1176 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
1177 else if (smp->remote_key_dist & SMP_DIST_SIGN)
1178 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
1181 static void sc_generate_ltk(struct smp_chan *smp)
1183 /* These constants are as specified in the core specification.
1184 * In ASCII they spell out to 'tmp2' and 'brle'.
1186 const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 };
1187 const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 };
1188 struct hci_conn *hcon = smp->conn->hcon;
1189 struct hci_dev *hdev = hcon->hdev;
1190 struct link_key *key;
1192 key = hci_find_link_key(hdev, &hcon->dst);
1193 if (!key) {
1194 BT_ERR("%s No Link Key found to generate LTK", hdev->name);
1195 return;
1198 if (key->type == HCI_LK_DEBUG_COMBINATION)
1199 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1201 if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk))
1202 return;
1204 if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk))
1205 return;
1207 sc_add_ltk(smp);
1210 static void smp_distribute_keys(struct smp_chan *smp)
1212 struct smp_cmd_pairing *req, *rsp;
1213 struct l2cap_conn *conn = smp->conn;
1214 struct hci_conn *hcon = conn->hcon;
1215 struct hci_dev *hdev = hcon->hdev;
1216 __u8 *keydist;
1218 BT_DBG("conn %p", conn);
1220 rsp = (void *) &smp->prsp[1];
1222 /* The responder sends its keys first */
1223 if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) {
1224 smp_allow_key_dist(smp);
1225 return;
1228 req = (void *) &smp->preq[1];
1230 if (hcon->out) {
1231 keydist = &rsp->init_key_dist;
1232 *keydist &= req->init_key_dist;
1233 } else {
1234 keydist = &rsp->resp_key_dist;
1235 *keydist &= req->resp_key_dist;
1238 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1239 if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY))
1240 sc_generate_link_key(smp);
1241 if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY))
1242 sc_generate_ltk(smp);
1244 /* Clear the keys which are generated but not distributed */
1245 *keydist &= ~SMP_SC_NO_DIST;
1248 BT_DBG("keydist 0x%x", *keydist);
1250 if (*keydist & SMP_DIST_ENC_KEY) {
1251 struct smp_cmd_encrypt_info enc;
1252 struct smp_cmd_master_ident ident;
1253 struct smp_ltk *ltk;
1254 u8 authenticated;
1255 __le16 ediv;
1256 __le64 rand;
1258 /* Make sure we generate only the significant amount of
1259 * bytes based on the encryption key size, and set the rest
1260 * of the value to zeroes.
1262 get_random_bytes(enc.ltk, smp->enc_key_size);
1263 memset(enc.ltk + smp->enc_key_size, 0,
1264 sizeof(enc.ltk) - smp->enc_key_size);
1266 get_random_bytes(&ediv, sizeof(ediv));
1267 get_random_bytes(&rand, sizeof(rand));
1269 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);
1271 authenticated = hcon->sec_level == BT_SECURITY_HIGH;
1272 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type,
1273 SMP_LTK_SLAVE, authenticated, enc.ltk,
1274 smp->enc_key_size, ediv, rand);
1275 smp->slave_ltk = ltk;
1277 ident.ediv = ediv;
1278 ident.rand = rand;
1280 smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident);
1282 *keydist &= ~SMP_DIST_ENC_KEY;
1285 if (*keydist & SMP_DIST_ID_KEY) {
1286 struct smp_cmd_ident_addr_info addrinfo;
1287 struct smp_cmd_ident_info idinfo;
1289 memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk));
1291 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);
1293 /* The hci_conn contains the local identity address
1294 * after the connection has been established.
1296 * This is true even when the connection has been
1297 * established using a resolvable random address.
1299 bacpy(&addrinfo.bdaddr, &hcon->src);
1300 addrinfo.addr_type = hcon->src_type;
1302 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo),
1303 &addrinfo);
1305 *keydist &= ~SMP_DIST_ID_KEY;
1308 if (*keydist & SMP_DIST_SIGN) {
1309 struct smp_cmd_sign_info sign;
1310 struct smp_csrk *csrk;
1312 /* Generate a new random key */
1313 get_random_bytes(sign.csrk, sizeof(sign.csrk));
1315 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
1316 if (csrk) {
1317 if (hcon->sec_level > BT_SECURITY_MEDIUM)
1318 csrk->type = MGMT_CSRK_LOCAL_AUTHENTICATED;
1319 else
1320 csrk->type = MGMT_CSRK_LOCAL_UNAUTHENTICATED;
1321 memcpy(csrk->val, sign.csrk, sizeof(csrk->val));
1323 smp->slave_csrk = csrk;
1325 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);
1327 *keydist &= ~SMP_DIST_SIGN;
1330 /* If there are still keys to be received wait for them */
1331 if (smp->remote_key_dist & KEY_DIST_MASK) {
1332 smp_allow_key_dist(smp);
1333 return;
1336 set_bit(SMP_FLAG_COMPLETE, &smp->flags);
1337 smp_notify_keys(conn);
1339 smp_chan_destroy(conn);
1342 static void smp_timeout(struct work_struct *work)
1344 struct smp_chan *smp = container_of(work, struct smp_chan,
1345 security_timer.work);
1346 struct l2cap_conn *conn = smp->conn;
1348 BT_DBG("conn %p", conn);
1350 hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM);
1353 static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
1355 struct l2cap_chan *chan = conn->smp;
1356 struct smp_chan *smp;
1358 smp = kzalloc(sizeof(*smp), GFP_ATOMIC);
1359 if (!smp)
1360 return NULL;
1362 smp->tfm_aes = crypto_alloc_skcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
1363 if (IS_ERR(smp->tfm_aes)) {
1364 BT_ERR("Unable to create ECB crypto context");
1365 kzfree(smp);
1366 return NULL;
1369 smp->tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
1370 if (IS_ERR(smp->tfm_cmac)) {
1371 BT_ERR("Unable to create CMAC crypto context");
1372 crypto_free_skcipher(smp->tfm_aes);
1373 kzfree(smp);
1374 return NULL;
1377 smp->conn = conn;
1378 chan->data = smp;
1380 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL);
1382 INIT_DELAYED_WORK(&smp->security_timer, smp_timeout);
1384 hci_conn_hold(conn->hcon);
1386 return smp;
1389 static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16])
1391 struct hci_conn *hcon = smp->conn->hcon;
1392 u8 *na, *nb, a[7], b[7];
1394 if (hcon->out) {
1395 na = smp->prnd;
1396 nb = smp->rrnd;
1397 } else {
1398 na = smp->rrnd;
1399 nb = smp->prnd;
1402 memcpy(a, &hcon->init_addr, 6);
1403 memcpy(b, &hcon->resp_addr, 6);
1404 a[6] = hcon->init_addr_type;
1405 b[6] = hcon->resp_addr_type;
1407 return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk);
1410 static void sc_dhkey_check(struct smp_chan *smp)
1412 struct hci_conn *hcon = smp->conn->hcon;
1413 struct smp_cmd_dhkey_check check;
1414 u8 a[7], b[7], *local_addr, *remote_addr;
1415 u8 io_cap[3], r[16];
1417 memcpy(a, &hcon->init_addr, 6);
1418 memcpy(b, &hcon->resp_addr, 6);
1419 a[6] = hcon->init_addr_type;
1420 b[6] = hcon->resp_addr_type;
1422 if (hcon->out) {
1423 local_addr = a;
1424 remote_addr = b;
1425 memcpy(io_cap, &smp->preq[1], 3);
1426 } else {
1427 local_addr = b;
1428 remote_addr = a;
1429 memcpy(io_cap, &smp->prsp[1], 3);
1432 memset(r, 0, sizeof(r));
1434 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
1435 put_unaligned_le32(hcon->passkey_notify, r);
1437 if (smp->method == REQ_OOB)
1438 memcpy(r, smp->rr, 16);
1440 smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap,
1441 local_addr, remote_addr, check.e);
1443 smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check);
1446 static u8 sc_passkey_send_confirm(struct smp_chan *smp)
1448 struct l2cap_conn *conn = smp->conn;
1449 struct hci_conn *hcon = conn->hcon;
1450 struct smp_cmd_pairing_confirm cfm;
1451 u8 r;
1453 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1454 r |= 0x80;
1456 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1458 if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r,
1459 cfm.confirm_val))
1460 return SMP_UNSPECIFIED;
1462 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
1464 return 0;
1467 static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op)
1469 struct l2cap_conn *conn = smp->conn;
1470 struct hci_conn *hcon = conn->hcon;
1471 struct hci_dev *hdev = hcon->hdev;
1472 u8 cfm[16], r;
1474 /* Ignore the PDU if we've already done 20 rounds (0 - 19) */
1475 if (smp->passkey_round >= 20)
1476 return 0;
1478 switch (smp_op) {
1479 case SMP_CMD_PAIRING_RANDOM:
1480 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1481 r |= 0x80;
1483 if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
1484 smp->rrnd, r, cfm))
1485 return SMP_UNSPECIFIED;
1487 if (memcmp(smp->pcnf, cfm, 16))
1488 return SMP_CONFIRM_FAILED;
1490 smp->passkey_round++;
1492 if (smp->passkey_round == 20) {
1493 /* Generate MacKey and LTK */
1494 if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk))
1495 return SMP_UNSPECIFIED;
1498 /* The round is only complete when the initiator
1499 * receives pairing random.
1501 if (!hcon->out) {
1502 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1503 sizeof(smp->prnd), smp->prnd);
1504 if (smp->passkey_round == 20)
1505 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1506 else
1507 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1508 return 0;
1511 /* Start the next round */
1512 if (smp->passkey_round != 20)
1513 return sc_passkey_round(smp, 0);
1515 /* Passkey rounds are complete - start DHKey Check */
1516 sc_dhkey_check(smp);
1517 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1519 break;
1521 case SMP_CMD_PAIRING_CONFIRM:
1522 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
1523 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
1524 return 0;
1527 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1529 if (hcon->out) {
1530 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1531 sizeof(smp->prnd), smp->prnd);
1532 return 0;
1535 return sc_passkey_send_confirm(smp);
1537 case SMP_CMD_PUBLIC_KEY:
1538 default:
1539 /* Initiating device starts the round */
1540 if (!hcon->out)
1541 return 0;
1543 BT_DBG("%s Starting passkey round %u", hdev->name,
1544 smp->passkey_round + 1);
1546 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1548 return sc_passkey_send_confirm(smp);
1551 return 0;
1554 static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey)
1556 struct l2cap_conn *conn = smp->conn;
1557 struct hci_conn *hcon = conn->hcon;
1558 u8 smp_op;
1560 clear_bit(SMP_FLAG_WAIT_USER, &smp->flags);
1562 switch (mgmt_op) {
1563 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1564 smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED);
1565 return 0;
1566 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1567 smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED);
1568 return 0;
1569 case MGMT_OP_USER_PASSKEY_REPLY:
1570 hcon->passkey_notify = le32_to_cpu(passkey);
1571 smp->passkey_round = 0;
1573 if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags))
1574 smp_op = SMP_CMD_PAIRING_CONFIRM;
1575 else
1576 smp_op = 0;
1578 if (sc_passkey_round(smp, smp_op))
1579 return -EIO;
1581 return 0;
1584 /* Initiator sends DHKey check first */
1585 if (hcon->out) {
1586 sc_dhkey_check(smp);
1587 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1588 } else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) {
1589 sc_dhkey_check(smp);
1590 sc_add_ltk(smp);
1593 return 0;
1596 int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
1598 struct l2cap_conn *conn = hcon->l2cap_data;
1599 struct l2cap_chan *chan;
1600 struct smp_chan *smp;
1601 u32 value;
1602 int err;
1604 BT_DBG("");
1606 if (!conn)
1607 return -ENOTCONN;
1609 chan = conn->smp;
1610 if (!chan)
1611 return -ENOTCONN;
1613 l2cap_chan_lock(chan);
1614 if (!chan->data) {
1615 err = -ENOTCONN;
1616 goto unlock;
1619 smp = chan->data;
1621 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1622 err = sc_user_reply(smp, mgmt_op, passkey);
1623 goto unlock;
1626 switch (mgmt_op) {
1627 case MGMT_OP_USER_PASSKEY_REPLY:
1628 value = le32_to_cpu(passkey);
1629 memset(smp->tk, 0, sizeof(smp->tk));
1630 BT_DBG("PassKey: %d", value);
1631 put_unaligned_le32(value, smp->tk);
1632 /* Fall Through */
1633 case MGMT_OP_USER_CONFIRM_REPLY:
1634 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
1635 break;
1636 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1637 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1638 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1639 err = 0;
1640 goto unlock;
1641 default:
1642 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1643 err = -EOPNOTSUPP;
1644 goto unlock;
1647 err = 0;
1649 /* If it is our turn to send Pairing Confirm, do so now */
1650 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) {
1651 u8 rsp = smp_confirm(smp);
1652 if (rsp)
1653 smp_failure(conn, rsp);
1656 unlock:
1657 l2cap_chan_unlock(chan);
1658 return err;
1661 static void build_bredr_pairing_cmd(struct smp_chan *smp,
1662 struct smp_cmd_pairing *req,
1663 struct smp_cmd_pairing *rsp)
1665 struct l2cap_conn *conn = smp->conn;
1666 struct hci_dev *hdev = conn->hcon->hdev;
1667 u8 local_dist = 0, remote_dist = 0;
1669 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
1670 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1671 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1674 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
1675 remote_dist |= SMP_DIST_ID_KEY;
1677 if (hci_dev_test_flag(hdev, HCI_PRIVACY))
1678 local_dist |= SMP_DIST_ID_KEY;
1680 if (!rsp) {
1681 memset(req, 0, sizeof(*req));
1683 req->init_key_dist = local_dist;
1684 req->resp_key_dist = remote_dist;
1685 req->max_key_size = conn->hcon->enc_key_size;
1687 smp->remote_key_dist = remote_dist;
1689 return;
1692 memset(rsp, 0, sizeof(*rsp));
1694 rsp->max_key_size = conn->hcon->enc_key_size;
1695 rsp->init_key_dist = req->init_key_dist & remote_dist;
1696 rsp->resp_key_dist = req->resp_key_dist & local_dist;
1698 smp->remote_key_dist = rsp->init_key_dist;
1701 static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
1703 struct smp_cmd_pairing rsp, *req = (void *) skb->data;
1704 struct l2cap_chan *chan = conn->smp;
1705 struct hci_dev *hdev = conn->hcon->hdev;
1706 struct smp_chan *smp;
1707 u8 key_size, auth, sec_level;
1708 int ret;
1710 BT_DBG("conn %p", conn);
1712 if (skb->len < sizeof(*req))
1713 return SMP_INVALID_PARAMS;
1715 if (conn->hcon->role != HCI_ROLE_SLAVE)
1716 return SMP_CMD_NOTSUPP;
1718 if (!chan->data)
1719 smp = smp_chan_create(conn);
1720 else
1721 smp = chan->data;
1723 if (!smp)
1724 return SMP_UNSPECIFIED;
1726 /* We didn't start the pairing, so match remote */
1727 auth = req->auth_req & AUTH_REQ_MASK(hdev);
1729 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
1730 (auth & SMP_AUTH_BONDING))
1731 return SMP_PAIRING_NOTSUPP;
1733 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1734 return SMP_AUTH_REQUIREMENTS;
1736 smp->preq[0] = SMP_CMD_PAIRING_REQ;
1737 memcpy(&smp->preq[1], req, sizeof(*req));
1738 skb_pull(skb, sizeof(*req));
1740 /* If the remote side's OOB flag is set it means it has
1741 * successfully received our local OOB data - therefore set the
1742 * flag to indicate that local OOB is in use.
1744 if (req->oob_flag == SMP_OOB_PRESENT)
1745 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1747 /* SMP over BR/EDR requires special treatment */
1748 if (conn->hcon->type == ACL_LINK) {
1749 /* We must have a BR/EDR SC link */
1750 if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) &&
1751 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
1752 return SMP_CROSS_TRANSP_NOT_ALLOWED;
1754 set_bit(SMP_FLAG_SC, &smp->flags);
1756 build_bredr_pairing_cmd(smp, req, &rsp);
1758 key_size = min(req->max_key_size, rsp.max_key_size);
1759 if (check_enc_key_size(conn, key_size))
1760 return SMP_ENC_KEY_SIZE;
1762 /* Clear bits which are generated but not distributed */
1763 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1765 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1766 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1767 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1769 smp_distribute_keys(smp);
1770 return 0;
1773 build_pairing_cmd(conn, req, &rsp, auth);
1775 if (rsp.auth_req & SMP_AUTH_SC)
1776 set_bit(SMP_FLAG_SC, &smp->flags);
1778 if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
1779 sec_level = BT_SECURITY_MEDIUM;
1780 else
1781 sec_level = authreq_to_seclevel(auth);
1783 if (sec_level > conn->hcon->pending_sec_level)
1784 conn->hcon->pending_sec_level = sec_level;
1786 /* If we need MITM check that it can be achieved */
1787 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1788 u8 method;
1790 method = get_auth_method(smp, conn->hcon->io_capability,
1791 req->io_capability);
1792 if (method == JUST_WORKS || method == JUST_CFM)
1793 return SMP_AUTH_REQUIREMENTS;
1796 key_size = min(req->max_key_size, rsp.max_key_size);
1797 if (check_enc_key_size(conn, key_size))
1798 return SMP_ENC_KEY_SIZE;
1800 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1802 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1803 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1805 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1807 clear_bit(SMP_FLAG_INITIATOR, &smp->flags);
1809 /* Strictly speaking we shouldn't allow Pairing Confirm for the
1810 * SC case, however some implementations incorrectly copy RFU auth
1811 * req bits from our security request, which may create a false
1812 * positive SC enablement.
1814 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1816 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1817 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
1818 /* Clear bits which are generated but not distributed */
1819 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1820 /* Wait for Public Key from Initiating Device */
1821 return 0;
1824 /* Request setup of TK */
1825 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability);
1826 if (ret)
1827 return SMP_UNSPECIFIED;
1829 return 0;
1832 static u8 sc_send_public_key(struct smp_chan *smp)
1834 struct hci_dev *hdev = smp->conn->hcon->hdev;
1836 BT_DBG("");
1838 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) {
1839 struct l2cap_chan *chan = hdev->smp_data;
1840 struct smp_dev *smp_dev;
1842 if (!chan || !chan->data)
1843 return SMP_UNSPECIFIED;
1845 smp_dev = chan->data;
1847 memcpy(smp->local_pk, smp_dev->local_pk, 64);
1848 memcpy(smp->local_sk, smp_dev->local_sk, 32);
1849 memcpy(smp->lr, smp_dev->local_rand, 16);
1851 if (smp_dev->debug_key)
1852 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1854 goto done;
1857 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
1858 BT_DBG("Using debug keys");
1859 memcpy(smp->local_pk, debug_pk, 64);
1860 memcpy(smp->local_sk, debug_sk, 32);
1861 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1862 } else {
1863 while (true) {
1864 /* Generate local key pair for Secure Connections */
1865 if (!ecc_make_key(smp->local_pk, smp->local_sk))
1866 return SMP_UNSPECIFIED;
1868 /* This is unlikely, but we need to check that
1869 * we didn't accidentially generate a debug key.
1871 if (memcmp(smp->local_sk, debug_sk, 32))
1872 break;
1876 done:
1877 SMP_DBG("Local Public Key X: %32phN", smp->local_pk);
1878 SMP_DBG("Local Public Key Y: %32phN", smp->local_pk + 32);
1879 SMP_DBG("Local Private Key: %32phN", smp->local_sk);
1881 smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk);
1883 return 0;
1886 static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
1888 struct smp_cmd_pairing *req, *rsp = (void *) skb->data;
1889 struct l2cap_chan *chan = conn->smp;
1890 struct smp_chan *smp = chan->data;
1891 struct hci_dev *hdev = conn->hcon->hdev;
1892 u8 key_size, auth;
1893 int ret;
1895 BT_DBG("conn %p", conn);
1897 if (skb->len < sizeof(*rsp))
1898 return SMP_INVALID_PARAMS;
1900 if (conn->hcon->role != HCI_ROLE_MASTER)
1901 return SMP_CMD_NOTSUPP;
1903 skb_pull(skb, sizeof(*rsp));
1905 req = (void *) &smp->preq[1];
1907 key_size = min(req->max_key_size, rsp->max_key_size);
1908 if (check_enc_key_size(conn, key_size))
1909 return SMP_ENC_KEY_SIZE;
1911 auth = rsp->auth_req & AUTH_REQ_MASK(hdev);
1913 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1914 return SMP_AUTH_REQUIREMENTS;
1916 /* If the remote side's OOB flag is set it means it has
1917 * successfully received our local OOB data - therefore set the
1918 * flag to indicate that local OOB is in use.
1920 if (rsp->oob_flag == SMP_OOB_PRESENT)
1921 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1923 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1924 memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
1926 /* Update remote key distribution in case the remote cleared
1927 * some bits that we had enabled in our request.
1929 smp->remote_key_dist &= rsp->resp_key_dist;
1931 /* For BR/EDR this means we're done and can start phase 3 */
1932 if (conn->hcon->type == ACL_LINK) {
1933 /* Clear bits which are generated but not distributed */
1934 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1935 smp_distribute_keys(smp);
1936 return 0;
1939 if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC))
1940 set_bit(SMP_FLAG_SC, &smp->flags);
1941 else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH)
1942 conn->hcon->pending_sec_level = BT_SECURITY_HIGH;
1944 /* If we need MITM check that it can be achieved */
1945 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1946 u8 method;
1948 method = get_auth_method(smp, req->io_capability,
1949 rsp->io_capability);
1950 if (method == JUST_WORKS || method == JUST_CFM)
1951 return SMP_AUTH_REQUIREMENTS;
1954 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1956 /* Update remote key distribution in case the remote cleared
1957 * some bits that we had enabled in our request.
1959 smp->remote_key_dist &= rsp->resp_key_dist;
1961 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1962 /* Clear bits which are generated but not distributed */
1963 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1964 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
1965 return sc_send_public_key(smp);
1968 auth |= req->auth_req;
1970 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability);
1971 if (ret)
1972 return SMP_UNSPECIFIED;
1974 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
1976 /* Can't compose response until we have been confirmed */
1977 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
1978 return smp_confirm(smp);
1980 return 0;
1983 static u8 sc_check_confirm(struct smp_chan *smp)
1985 struct l2cap_conn *conn = smp->conn;
1987 BT_DBG("");
1989 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
1990 return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM);
1992 if (conn->hcon->out) {
1993 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1994 smp->prnd);
1995 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1998 return 0;
2001 /* Work-around for some implementations that incorrectly copy RFU bits
2002 * from our security request and thereby create the impression that
2003 * we're doing SC when in fact the remote doesn't support it.
2005 static int fixup_sc_false_positive(struct smp_chan *smp)
2007 struct l2cap_conn *conn = smp->conn;
2008 struct hci_conn *hcon = conn->hcon;
2009 struct hci_dev *hdev = hcon->hdev;
2010 struct smp_cmd_pairing *req, *rsp;
2011 u8 auth;
2013 /* The issue is only observed when we're in slave role */
2014 if (hcon->out)
2015 return SMP_UNSPECIFIED;
2017 if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) {
2018 BT_ERR("Refusing SMP SC -> legacy fallback in SC-only mode");
2019 return SMP_UNSPECIFIED;
2022 BT_ERR("Trying to fall back to legacy SMP");
2024 req = (void *) &smp->preq[1];
2025 rsp = (void *) &smp->prsp[1];
2027 /* Rebuild key dist flags which may have been cleared for SC */
2028 smp->remote_key_dist = (req->init_key_dist & rsp->resp_key_dist);
2030 auth = req->auth_req & AUTH_REQ_MASK(hdev);
2032 if (tk_request(conn, 0, auth, rsp->io_capability, req->io_capability)) {
2033 BT_ERR("Failed to fall back to legacy SMP");
2034 return SMP_UNSPECIFIED;
2037 clear_bit(SMP_FLAG_SC, &smp->flags);
2039 return 0;
2042 static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
2044 struct l2cap_chan *chan = conn->smp;
2045 struct smp_chan *smp = chan->data;
2047 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
2049 if (skb->len < sizeof(smp->pcnf))
2050 return SMP_INVALID_PARAMS;
2052 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
2053 skb_pull(skb, sizeof(smp->pcnf));
2055 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
2056 int ret;
2058 /* Public Key exchange must happen before any other steps */
2059 if (test_bit(SMP_FLAG_REMOTE_PK, &smp->flags))
2060 return sc_check_confirm(smp);
2062 BT_ERR("Unexpected SMP Pairing Confirm");
2064 ret = fixup_sc_false_positive(smp);
2065 if (ret)
2066 return ret;
2069 if (conn->hcon->out) {
2070 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2071 smp->prnd);
2072 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2073 return 0;
2076 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
2077 return smp_confirm(smp);
2079 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
2081 return 0;
2084 static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
2086 struct l2cap_chan *chan = conn->smp;
2087 struct smp_chan *smp = chan->data;
2088 struct hci_conn *hcon = conn->hcon;
2089 u8 *pkax, *pkbx, *na, *nb;
2090 u32 passkey;
2091 int err;
2093 BT_DBG("conn %p", conn);
2095 if (skb->len < sizeof(smp->rrnd))
2096 return SMP_INVALID_PARAMS;
2098 memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd));
2099 skb_pull(skb, sizeof(smp->rrnd));
2101 if (!test_bit(SMP_FLAG_SC, &smp->flags))
2102 return smp_random(smp);
2104 if (hcon->out) {
2105 pkax = smp->local_pk;
2106 pkbx = smp->remote_pk;
2107 na = smp->prnd;
2108 nb = smp->rrnd;
2109 } else {
2110 pkax = smp->remote_pk;
2111 pkbx = smp->local_pk;
2112 na = smp->rrnd;
2113 nb = smp->prnd;
2116 if (smp->method == REQ_OOB) {
2117 if (!hcon->out)
2118 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2119 sizeof(smp->prnd), smp->prnd);
2120 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2121 goto mackey_and_ltk;
2124 /* Passkey entry has special treatment */
2125 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2126 return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM);
2128 if (hcon->out) {
2129 u8 cfm[16];
2131 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
2132 smp->rrnd, 0, cfm);
2133 if (err)
2134 return SMP_UNSPECIFIED;
2136 if (memcmp(smp->pcnf, cfm, 16))
2137 return SMP_CONFIRM_FAILED;
2138 } else {
2139 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2140 smp->prnd);
2141 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2144 mackey_and_ltk:
2145 /* Generate MacKey and LTK */
2146 err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk);
2147 if (err)
2148 return SMP_UNSPECIFIED;
2150 if (smp->method == JUST_WORKS || smp->method == REQ_OOB) {
2151 if (hcon->out) {
2152 sc_dhkey_check(smp);
2153 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2155 return 0;
2158 err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);
2159 if (err)
2160 return SMP_UNSPECIFIED;
2162 err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type,
2163 hcon->dst_type, passkey, 0);
2164 if (err)
2165 return SMP_UNSPECIFIED;
2167 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2169 return 0;
2172 static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
2174 struct smp_ltk *key;
2175 struct hci_conn *hcon = conn->hcon;
2177 key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role);
2178 if (!key)
2179 return false;
2181 if (smp_ltk_sec_level(key) < sec_level)
2182 return false;
2184 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
2185 return true;
2187 hci_le_start_enc(hcon, key->ediv, key->rand, key->val, key->enc_size);
2188 hcon->enc_key_size = key->enc_size;
2190 /* We never store STKs for master role, so clear this flag */
2191 clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
2193 return true;
2196 bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level,
2197 enum smp_key_pref key_pref)
2199 if (sec_level == BT_SECURITY_LOW)
2200 return true;
2202 /* If we're encrypted with an STK but the caller prefers using
2203 * LTK claim insufficient security. This way we allow the
2204 * connection to be re-encrypted with an LTK, even if the LTK
2205 * provides the same level of security. Only exception is if we
2206 * don't have an LTK (e.g. because of key distribution bits).
2208 if (key_pref == SMP_USE_LTK &&
2209 test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) &&
2210 hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role))
2211 return false;
2213 if (hcon->sec_level >= sec_level)
2214 return true;
2216 return false;
2219 static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
2221 struct smp_cmd_security_req *rp = (void *) skb->data;
2222 struct smp_cmd_pairing cp;
2223 struct hci_conn *hcon = conn->hcon;
2224 struct hci_dev *hdev = hcon->hdev;
2225 struct smp_chan *smp;
2226 u8 sec_level, auth;
2228 BT_DBG("conn %p", conn);
2230 if (skb->len < sizeof(*rp))
2231 return SMP_INVALID_PARAMS;
2233 if (hcon->role != HCI_ROLE_MASTER)
2234 return SMP_CMD_NOTSUPP;
2236 auth = rp->auth_req & AUTH_REQ_MASK(hdev);
2238 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
2239 return SMP_AUTH_REQUIREMENTS;
2241 if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
2242 sec_level = BT_SECURITY_MEDIUM;
2243 else
2244 sec_level = authreq_to_seclevel(auth);
2246 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
2247 return 0;
2249 if (sec_level > hcon->pending_sec_level)
2250 hcon->pending_sec_level = sec_level;
2252 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2253 return 0;
2255 smp = smp_chan_create(conn);
2256 if (!smp)
2257 return SMP_UNSPECIFIED;
2259 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
2260 (auth & SMP_AUTH_BONDING))
2261 return SMP_PAIRING_NOTSUPP;
2263 skb_pull(skb, sizeof(*rp));
2265 memset(&cp, 0, sizeof(cp));
2266 build_pairing_cmd(conn, &cp, NULL, auth);
2268 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2269 memcpy(&smp->preq[1], &cp, sizeof(cp));
2271 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2272 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2274 return 0;
2277 int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
2279 struct l2cap_conn *conn = hcon->l2cap_data;
2280 struct l2cap_chan *chan;
2281 struct smp_chan *smp;
2282 __u8 authreq;
2283 int ret;
2285 BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);
2287 /* This may be NULL if there's an unexpected disconnection */
2288 if (!conn)
2289 return 1;
2291 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED))
2292 return 1;
2294 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
2295 return 1;
2297 if (sec_level > hcon->pending_sec_level)
2298 hcon->pending_sec_level = sec_level;
2300 if (hcon->role == HCI_ROLE_MASTER)
2301 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2302 return 0;
2304 chan = conn->smp;
2305 if (!chan) {
2306 BT_ERR("SMP security requested but not available");
2307 return 1;
2310 l2cap_chan_lock(chan);
2312 /* If SMP is already in progress ignore this request */
2313 if (chan->data) {
2314 ret = 0;
2315 goto unlock;
2318 smp = smp_chan_create(conn);
2319 if (!smp) {
2320 ret = 1;
2321 goto unlock;
2324 authreq = seclevel_to_authreq(sec_level);
2326 if (hci_dev_test_flag(hcon->hdev, HCI_SC_ENABLED))
2327 authreq |= SMP_AUTH_SC;
2329 /* Require MITM if IO Capability allows or the security level
2330 * requires it.
2332 if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT ||
2333 hcon->pending_sec_level > BT_SECURITY_MEDIUM)
2334 authreq |= SMP_AUTH_MITM;
2336 if (hcon->role == HCI_ROLE_MASTER) {
2337 struct smp_cmd_pairing cp;
2339 build_pairing_cmd(conn, &cp, NULL, authreq);
2340 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2341 memcpy(&smp->preq[1], &cp, sizeof(cp));
2343 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2344 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2345 } else {
2346 struct smp_cmd_security_req cp;
2347 cp.auth_req = authreq;
2348 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
2349 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ);
2352 set_bit(SMP_FLAG_INITIATOR, &smp->flags);
2353 ret = 0;
2355 unlock:
2356 l2cap_chan_unlock(chan);
2357 return ret;
2360 void smp_cancel_pairing(struct hci_conn *hcon)
2362 struct l2cap_conn *conn = hcon->l2cap_data;
2363 struct l2cap_chan *chan;
2364 struct smp_chan *smp;
2366 if (!conn)
2367 return;
2369 chan = conn->smp;
2370 if (!chan)
2371 return;
2373 l2cap_chan_lock(chan);
2375 smp = chan->data;
2376 if (smp) {
2377 if (test_bit(SMP_FLAG_COMPLETE, &smp->flags))
2378 smp_failure(conn, 0);
2379 else
2380 smp_failure(conn, SMP_UNSPECIFIED);
2383 l2cap_chan_unlock(chan);
2386 static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb)
2388 struct smp_cmd_encrypt_info *rp = (void *) skb->data;
2389 struct l2cap_chan *chan = conn->smp;
2390 struct smp_chan *smp = chan->data;
2392 BT_DBG("conn %p", conn);
2394 if (skb->len < sizeof(*rp))
2395 return SMP_INVALID_PARAMS;
2397 SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT);
2399 skb_pull(skb, sizeof(*rp));
2401 memcpy(smp->tk, rp->ltk, sizeof(smp->tk));
2403 return 0;
2406 static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
2408 struct smp_cmd_master_ident *rp = (void *) skb->data;
2409 struct l2cap_chan *chan = conn->smp;
2410 struct smp_chan *smp = chan->data;
2411 struct hci_dev *hdev = conn->hcon->hdev;
2412 struct hci_conn *hcon = conn->hcon;
2413 struct smp_ltk *ltk;
2414 u8 authenticated;
2416 BT_DBG("conn %p", conn);
2418 if (skb->len < sizeof(*rp))
2419 return SMP_INVALID_PARAMS;
2421 /* Mark the information as received */
2422 smp->remote_key_dist &= ~SMP_DIST_ENC_KEY;
2424 if (smp->remote_key_dist & SMP_DIST_ID_KEY)
2425 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
2426 else if (smp->remote_key_dist & SMP_DIST_SIGN)
2427 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2429 skb_pull(skb, sizeof(*rp));
2431 authenticated = (hcon->sec_level == BT_SECURITY_HIGH);
2432 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK,
2433 authenticated, smp->tk, smp->enc_key_size,
2434 rp->ediv, rp->rand);
2435 smp->ltk = ltk;
2436 if (!(smp->remote_key_dist & KEY_DIST_MASK))
2437 smp_distribute_keys(smp);
2439 return 0;
2442 static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb)
2444 struct smp_cmd_ident_info *info = (void *) skb->data;
2445 struct l2cap_chan *chan = conn->smp;
2446 struct smp_chan *smp = chan->data;
2448 BT_DBG("");
2450 if (skb->len < sizeof(*info))
2451 return SMP_INVALID_PARAMS;
2453 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO);
2455 skb_pull(skb, sizeof(*info));
2457 memcpy(smp->irk, info->irk, 16);
2459 return 0;
2462 static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,
2463 struct sk_buff *skb)
2465 struct smp_cmd_ident_addr_info *info = (void *) skb->data;
2466 struct l2cap_chan *chan = conn->smp;
2467 struct smp_chan *smp = chan->data;
2468 struct hci_conn *hcon = conn->hcon;
2469 bdaddr_t rpa;
2471 BT_DBG("");
2473 if (skb->len < sizeof(*info))
2474 return SMP_INVALID_PARAMS;
2476 /* Mark the information as received */
2477 smp->remote_key_dist &= ~SMP_DIST_ID_KEY;
2479 if (smp->remote_key_dist & SMP_DIST_SIGN)
2480 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2482 skb_pull(skb, sizeof(*info));
2484 /* Strictly speaking the Core Specification (4.1) allows sending
2485 * an empty address which would force us to rely on just the IRK
2486 * as "identity information". However, since such
2487 * implementations are not known of and in order to not over
2488 * complicate our implementation, simply pretend that we never
2489 * received an IRK for such a device.
2491 * The Identity Address must also be a Static Random or Public
2492 * Address, which hci_is_identity_address() checks for.
2494 if (!bacmp(&info->bdaddr, BDADDR_ANY) ||
2495 !hci_is_identity_address(&info->bdaddr, info->addr_type)) {
2496 BT_ERR("Ignoring IRK with no identity address");
2497 goto distribute;
2500 bacpy(&smp->id_addr, &info->bdaddr);
2501 smp->id_addr_type = info->addr_type;
2503 if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type))
2504 bacpy(&rpa, &hcon->dst);
2505 else
2506 bacpy(&rpa, BDADDR_ANY);
2508 smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr,
2509 smp->id_addr_type, smp->irk, &rpa);
2511 distribute:
2512 if (!(smp->remote_key_dist & KEY_DIST_MASK))
2513 smp_distribute_keys(smp);
2515 return 0;
2518 static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb)
2520 struct smp_cmd_sign_info *rp = (void *) skb->data;
2521 struct l2cap_chan *chan = conn->smp;
2522 struct smp_chan *smp = chan->data;
2523 struct smp_csrk *csrk;
2525 BT_DBG("conn %p", conn);
2527 if (skb->len < sizeof(*rp))
2528 return SMP_INVALID_PARAMS;
2530 /* Mark the information as received */
2531 smp->remote_key_dist &= ~SMP_DIST_SIGN;
2533 skb_pull(skb, sizeof(*rp));
2535 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
2536 if (csrk) {
2537 if (conn->hcon->sec_level > BT_SECURITY_MEDIUM)
2538 csrk->type = MGMT_CSRK_REMOTE_AUTHENTICATED;
2539 else
2540 csrk->type = MGMT_CSRK_REMOTE_UNAUTHENTICATED;
2541 memcpy(csrk->val, rp->csrk, sizeof(csrk->val));
2543 smp->csrk = csrk;
2544 smp_distribute_keys(smp);
2546 return 0;
2549 static u8 sc_select_method(struct smp_chan *smp)
2551 struct l2cap_conn *conn = smp->conn;
2552 struct hci_conn *hcon = conn->hcon;
2553 struct smp_cmd_pairing *local, *remote;
2554 u8 local_mitm, remote_mitm, local_io, remote_io, method;
2556 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags) ||
2557 test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags))
2558 return REQ_OOB;
2560 /* The preq/prsp contain the raw Pairing Request/Response PDUs
2561 * which are needed as inputs to some crypto functions. To get
2562 * the "struct smp_cmd_pairing" from them we need to skip the
2563 * first byte which contains the opcode.
2565 if (hcon->out) {
2566 local = (void *) &smp->preq[1];
2567 remote = (void *) &smp->prsp[1];
2568 } else {
2569 local = (void *) &smp->prsp[1];
2570 remote = (void *) &smp->preq[1];
2573 local_io = local->io_capability;
2574 remote_io = remote->io_capability;
2576 local_mitm = (local->auth_req & SMP_AUTH_MITM);
2577 remote_mitm = (remote->auth_req & SMP_AUTH_MITM);
2579 /* If either side wants MITM, look up the method from the table,
2580 * otherwise use JUST WORKS.
2582 if (local_mitm || remote_mitm)
2583 method = get_auth_method(smp, local_io, remote_io);
2584 else
2585 method = JUST_WORKS;
2587 /* Don't confirm locally initiated pairing attempts */
2588 if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags))
2589 method = JUST_WORKS;
2591 return method;
2594 static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb)
2596 struct smp_cmd_public_key *key = (void *) skb->data;
2597 struct hci_conn *hcon = conn->hcon;
2598 struct l2cap_chan *chan = conn->smp;
2599 struct smp_chan *smp = chan->data;
2600 struct hci_dev *hdev = hcon->hdev;
2601 struct smp_cmd_pairing_confirm cfm;
2602 int err;
2604 BT_DBG("conn %p", conn);
2606 if (skb->len < sizeof(*key))
2607 return SMP_INVALID_PARAMS;
2609 memcpy(smp->remote_pk, key, 64);
2611 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags)) {
2612 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk,
2613 smp->rr, 0, cfm.confirm_val);
2614 if (err)
2615 return SMP_UNSPECIFIED;
2617 if (memcmp(cfm.confirm_val, smp->pcnf, 16))
2618 return SMP_CONFIRM_FAILED;
2621 /* Non-initiating device sends its public key after receiving
2622 * the key from the initiating device.
2624 if (!hcon->out) {
2625 err = sc_send_public_key(smp);
2626 if (err)
2627 return err;
2630 SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk);
2631 SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32);
2633 if (!ecdh_shared_secret(smp->remote_pk, smp->local_sk, smp->dhkey))
2634 return SMP_UNSPECIFIED;
2636 SMP_DBG("DHKey %32phN", smp->dhkey);
2638 set_bit(SMP_FLAG_REMOTE_PK, &smp->flags);
2640 smp->method = sc_select_method(smp);
2642 BT_DBG("%s selected method 0x%02x", hdev->name, smp->method);
2644 /* JUST_WORKS and JUST_CFM result in an unauthenticated key */
2645 if (smp->method == JUST_WORKS || smp->method == JUST_CFM)
2646 hcon->pending_sec_level = BT_SECURITY_MEDIUM;
2647 else
2648 hcon->pending_sec_level = BT_SECURITY_FIPS;
2650 if (!memcmp(debug_pk, smp->remote_pk, 64))
2651 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
2653 if (smp->method == DSP_PASSKEY) {
2654 get_random_bytes(&hcon->passkey_notify,
2655 sizeof(hcon->passkey_notify));
2656 hcon->passkey_notify %= 1000000;
2657 hcon->passkey_entered = 0;
2658 smp->passkey_round = 0;
2659 if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type,
2660 hcon->dst_type,
2661 hcon->passkey_notify,
2662 hcon->passkey_entered))
2663 return SMP_UNSPECIFIED;
2664 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2665 return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY);
2668 if (smp->method == REQ_OOB) {
2669 if (hcon->out)
2670 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2671 sizeof(smp->prnd), smp->prnd);
2673 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2675 return 0;
2678 if (hcon->out)
2679 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2681 if (smp->method == REQ_PASSKEY) {
2682 if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type,
2683 hcon->dst_type))
2684 return SMP_UNSPECIFIED;
2685 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2686 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2687 return 0;
2690 /* The Initiating device waits for the non-initiating device to
2691 * send the confirm value.
2693 if (conn->hcon->out)
2694 return 0;
2696 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd,
2697 0, cfm.confirm_val);
2698 if (err)
2699 return SMP_UNSPECIFIED;
2701 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
2702 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2704 return 0;
2707 static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb)
2709 struct smp_cmd_dhkey_check *check = (void *) skb->data;
2710 struct l2cap_chan *chan = conn->smp;
2711 struct hci_conn *hcon = conn->hcon;
2712 struct smp_chan *smp = chan->data;
2713 u8 a[7], b[7], *local_addr, *remote_addr;
2714 u8 io_cap[3], r[16], e[16];
2715 int err;
2717 BT_DBG("conn %p", conn);
2719 if (skb->len < sizeof(*check))
2720 return SMP_INVALID_PARAMS;
2722 memcpy(a, &hcon->init_addr, 6);
2723 memcpy(b, &hcon->resp_addr, 6);
2724 a[6] = hcon->init_addr_type;
2725 b[6] = hcon->resp_addr_type;
2727 if (hcon->out) {
2728 local_addr = a;
2729 remote_addr = b;
2730 memcpy(io_cap, &smp->prsp[1], 3);
2731 } else {
2732 local_addr = b;
2733 remote_addr = a;
2734 memcpy(io_cap, &smp->preq[1], 3);
2737 memset(r, 0, sizeof(r));
2739 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2740 put_unaligned_le32(hcon->passkey_notify, r);
2741 else if (smp->method == REQ_OOB)
2742 memcpy(r, smp->lr, 16);
2744 err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r,
2745 io_cap, remote_addr, local_addr, e);
2746 if (err)
2747 return SMP_UNSPECIFIED;
2749 if (memcmp(check->e, e, 16))
2750 return SMP_DHKEY_CHECK_FAILED;
2752 if (!hcon->out) {
2753 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
2754 set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags);
2755 return 0;
2758 /* Slave sends DHKey check as response to master */
2759 sc_dhkey_check(smp);
2762 sc_add_ltk(smp);
2764 if (hcon->out) {
2765 hci_le_start_enc(hcon, 0, 0, smp->tk, smp->enc_key_size);
2766 hcon->enc_key_size = smp->enc_key_size;
2769 return 0;
2772 static int smp_cmd_keypress_notify(struct l2cap_conn *conn,
2773 struct sk_buff *skb)
2775 struct smp_cmd_keypress_notify *kp = (void *) skb->data;
2777 BT_DBG("value 0x%02x", kp->value);
2779 return 0;
2782 static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb)
2784 struct l2cap_conn *conn = chan->conn;
2785 struct hci_conn *hcon = conn->hcon;
2786 struct smp_chan *smp;
2787 __u8 code, reason;
2788 int err = 0;
2790 if (skb->len < 1)
2791 return -EILSEQ;
2793 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) {
2794 reason = SMP_PAIRING_NOTSUPP;
2795 goto done;
2798 code = skb->data[0];
2799 skb_pull(skb, sizeof(code));
2801 smp = chan->data;
2803 if (code > SMP_CMD_MAX)
2804 goto drop;
2806 if (smp && !test_and_clear_bit(code, &smp->allow_cmd))
2807 goto drop;
2809 /* If we don't have a context the only allowed commands are
2810 * pairing request and security request.
2812 if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ)
2813 goto drop;
2815 switch (code) {
2816 case SMP_CMD_PAIRING_REQ:
2817 reason = smp_cmd_pairing_req(conn, skb);
2818 break;
2820 case SMP_CMD_PAIRING_FAIL:
2821 smp_failure(conn, 0);
2822 err = -EPERM;
2823 break;
2825 case SMP_CMD_PAIRING_RSP:
2826 reason = smp_cmd_pairing_rsp(conn, skb);
2827 break;
2829 case SMP_CMD_SECURITY_REQ:
2830 reason = smp_cmd_security_req(conn, skb);
2831 break;
2833 case SMP_CMD_PAIRING_CONFIRM:
2834 reason = smp_cmd_pairing_confirm(conn, skb);
2835 break;
2837 case SMP_CMD_PAIRING_RANDOM:
2838 reason = smp_cmd_pairing_random(conn, skb);
2839 break;
2841 case SMP_CMD_ENCRYPT_INFO:
2842 reason = smp_cmd_encrypt_info(conn, skb);
2843 break;
2845 case SMP_CMD_MASTER_IDENT:
2846 reason = smp_cmd_master_ident(conn, skb);
2847 break;
2849 case SMP_CMD_IDENT_INFO:
2850 reason = smp_cmd_ident_info(conn, skb);
2851 break;
2853 case SMP_CMD_IDENT_ADDR_INFO:
2854 reason = smp_cmd_ident_addr_info(conn, skb);
2855 break;
2857 case SMP_CMD_SIGN_INFO:
2858 reason = smp_cmd_sign_info(conn, skb);
2859 break;
2861 case SMP_CMD_PUBLIC_KEY:
2862 reason = smp_cmd_public_key(conn, skb);
2863 break;
2865 case SMP_CMD_DHKEY_CHECK:
2866 reason = smp_cmd_dhkey_check(conn, skb);
2867 break;
2869 case SMP_CMD_KEYPRESS_NOTIFY:
2870 reason = smp_cmd_keypress_notify(conn, skb);
2871 break;
2873 default:
2874 BT_DBG("Unknown command code 0x%2.2x", code);
2875 reason = SMP_CMD_NOTSUPP;
2876 goto done;
2879 done:
2880 if (!err) {
2881 if (reason)
2882 smp_failure(conn, reason);
2883 kfree_skb(skb);
2886 return err;
2888 drop:
2889 BT_ERR("%s unexpected SMP command 0x%02x from %pMR", hcon->hdev->name,
2890 code, &hcon->dst);
2891 kfree_skb(skb);
2892 return 0;
2895 static void smp_teardown_cb(struct l2cap_chan *chan, int err)
2897 struct l2cap_conn *conn = chan->conn;
2899 BT_DBG("chan %p", chan);
2901 if (chan->data)
2902 smp_chan_destroy(conn);
2904 conn->smp = NULL;
2905 l2cap_chan_put(chan);
2908 static void bredr_pairing(struct l2cap_chan *chan)
2910 struct l2cap_conn *conn = chan->conn;
2911 struct hci_conn *hcon = conn->hcon;
2912 struct hci_dev *hdev = hcon->hdev;
2913 struct smp_cmd_pairing req;
2914 struct smp_chan *smp;
2916 BT_DBG("chan %p", chan);
2918 /* Only new pairings are interesting */
2919 if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags))
2920 return;
2922 /* Don't bother if we're not encrypted */
2923 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
2924 return;
2926 /* Only master may initiate SMP over BR/EDR */
2927 if (hcon->role != HCI_ROLE_MASTER)
2928 return;
2930 /* Secure Connections support must be enabled */
2931 if (!hci_dev_test_flag(hdev, HCI_SC_ENABLED))
2932 return;
2934 /* BR/EDR must use Secure Connections for SMP */
2935 if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) &&
2936 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
2937 return;
2939 /* If our LE support is not enabled don't do anything */
2940 if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED))
2941 return;
2943 /* Don't bother if remote LE support is not enabled */
2944 if (!lmp_host_le_capable(hcon))
2945 return;
2947 /* Remote must support SMP fixed chan for BR/EDR */
2948 if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR))
2949 return;
2951 /* Don't bother if SMP is already ongoing */
2952 if (chan->data)
2953 return;
2955 smp = smp_chan_create(conn);
2956 if (!smp) {
2957 BT_ERR("%s unable to create SMP context for BR/EDR",
2958 hdev->name);
2959 return;
2962 set_bit(SMP_FLAG_SC, &smp->flags);
2964 BT_DBG("%s starting SMP over BR/EDR", hdev->name);
2966 /* Prepare and send the BR/EDR SMP Pairing Request */
2967 build_bredr_pairing_cmd(smp, &req, NULL);
2969 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2970 memcpy(&smp->preq[1], &req, sizeof(req));
2972 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req);
2973 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2976 static void smp_resume_cb(struct l2cap_chan *chan)
2978 struct smp_chan *smp = chan->data;
2979 struct l2cap_conn *conn = chan->conn;
2980 struct hci_conn *hcon = conn->hcon;
2982 BT_DBG("chan %p", chan);
2984 if (hcon->type == ACL_LINK) {
2985 bredr_pairing(chan);
2986 return;
2989 if (!smp)
2990 return;
2992 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
2993 return;
2995 cancel_delayed_work(&smp->security_timer);
2997 smp_distribute_keys(smp);
3000 static void smp_ready_cb(struct l2cap_chan *chan)
3002 struct l2cap_conn *conn = chan->conn;
3003 struct hci_conn *hcon = conn->hcon;
3005 BT_DBG("chan %p", chan);
3007 /* No need to call l2cap_chan_hold() here since we already own
3008 * the reference taken in smp_new_conn_cb(). This is just the
3009 * first time that we tie it to a specific pointer. The code in
3010 * l2cap_core.c ensures that there's no risk this function wont
3011 * get called if smp_new_conn_cb was previously called.
3013 conn->smp = chan;
3015 if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
3016 bredr_pairing(chan);
3019 static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
3021 int err;
3023 BT_DBG("chan %p", chan);
3025 err = smp_sig_channel(chan, skb);
3026 if (err) {
3027 struct smp_chan *smp = chan->data;
3029 if (smp)
3030 cancel_delayed_work_sync(&smp->security_timer);
3032 hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE);
3035 return err;
3038 static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan,
3039 unsigned long hdr_len,
3040 unsigned long len, int nb)
3042 struct sk_buff *skb;
3044 skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL);
3045 if (!skb)
3046 return ERR_PTR(-ENOMEM);
3048 skb->priority = HCI_PRIO_MAX;
3049 bt_cb(skb)->l2cap.chan = chan;
3051 return skb;
3054 static const struct l2cap_ops smp_chan_ops = {
3055 .name = "Security Manager",
3056 .ready = smp_ready_cb,
3057 .recv = smp_recv_cb,
3058 .alloc_skb = smp_alloc_skb_cb,
3059 .teardown = smp_teardown_cb,
3060 .resume = smp_resume_cb,
3062 .new_connection = l2cap_chan_no_new_connection,
3063 .state_change = l2cap_chan_no_state_change,
3064 .close = l2cap_chan_no_close,
3065 .defer = l2cap_chan_no_defer,
3066 .suspend = l2cap_chan_no_suspend,
3067 .set_shutdown = l2cap_chan_no_set_shutdown,
3068 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
3071 static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan)
3073 struct l2cap_chan *chan;
3075 BT_DBG("pchan %p", pchan);
3077 chan = l2cap_chan_create();
3078 if (!chan)
3079 return NULL;
3081 chan->chan_type = pchan->chan_type;
3082 chan->ops = &smp_chan_ops;
3083 chan->scid = pchan->scid;
3084 chan->dcid = chan->scid;
3085 chan->imtu = pchan->imtu;
3086 chan->omtu = pchan->omtu;
3087 chan->mode = pchan->mode;
3089 /* Other L2CAP channels may request SMP routines in order to
3090 * change the security level. This means that the SMP channel
3091 * lock must be considered in its own category to avoid lockdep
3092 * warnings.
3094 atomic_set(&chan->nesting, L2CAP_NESTING_SMP);
3096 BT_DBG("created chan %p", chan);
3098 return chan;
3101 static const struct l2cap_ops smp_root_chan_ops = {
3102 .name = "Security Manager Root",
3103 .new_connection = smp_new_conn_cb,
3105 /* None of these are implemented for the root channel */
3106 .close = l2cap_chan_no_close,
3107 .alloc_skb = l2cap_chan_no_alloc_skb,
3108 .recv = l2cap_chan_no_recv,
3109 .state_change = l2cap_chan_no_state_change,
3110 .teardown = l2cap_chan_no_teardown,
3111 .ready = l2cap_chan_no_ready,
3112 .defer = l2cap_chan_no_defer,
3113 .suspend = l2cap_chan_no_suspend,
3114 .resume = l2cap_chan_no_resume,
3115 .set_shutdown = l2cap_chan_no_set_shutdown,
3116 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
3119 static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid)
3121 struct l2cap_chan *chan;
3122 struct smp_dev *smp;
3123 struct crypto_skcipher *tfm_aes;
3124 struct crypto_shash *tfm_cmac;
3126 if (cid == L2CAP_CID_SMP_BREDR) {
3127 smp = NULL;
3128 goto create_chan;
3131 smp = kzalloc(sizeof(*smp), GFP_KERNEL);
3132 if (!smp)
3133 return ERR_PTR(-ENOMEM);
3135 tfm_aes = crypto_alloc_skcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
3136 if (IS_ERR(tfm_aes)) {
3137 BT_ERR("Unable to create ECB crypto context");
3138 kzfree(smp);
3139 return ERR_CAST(tfm_aes);
3142 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
3143 if (IS_ERR(tfm_cmac)) {
3144 BT_ERR("Unable to create CMAC crypto context");
3145 crypto_free_skcipher(tfm_aes);
3146 kzfree(smp);
3147 return ERR_CAST(tfm_cmac);
3150 smp->tfm_aes = tfm_aes;
3151 smp->tfm_cmac = tfm_cmac;
3152 smp->min_key_size = SMP_MIN_ENC_KEY_SIZE;
3153 smp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
3155 create_chan:
3156 chan = l2cap_chan_create();
3157 if (!chan) {
3158 if (smp) {
3159 crypto_free_skcipher(smp->tfm_aes);
3160 crypto_free_shash(smp->tfm_cmac);
3161 kzfree(smp);
3163 return ERR_PTR(-ENOMEM);
3166 chan->data = smp;
3168 l2cap_add_scid(chan, cid);
3170 l2cap_chan_set_defaults(chan);
3172 if (cid == L2CAP_CID_SMP) {
3173 u8 bdaddr_type;
3175 hci_copy_identity_address(hdev, &chan->src, &bdaddr_type);
3177 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
3178 chan->src_type = BDADDR_LE_PUBLIC;
3179 else
3180 chan->src_type = BDADDR_LE_RANDOM;
3181 } else {
3182 bacpy(&chan->src, &hdev->bdaddr);
3183 chan->src_type = BDADDR_BREDR;
3186 chan->state = BT_LISTEN;
3187 chan->mode = L2CAP_MODE_BASIC;
3188 chan->imtu = L2CAP_DEFAULT_MTU;
3189 chan->ops = &smp_root_chan_ops;
3191 /* Set correct nesting level for a parent/listening channel */
3192 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
3194 return chan;
3197 static void smp_del_chan(struct l2cap_chan *chan)
3199 struct smp_dev *smp;
3201 BT_DBG("chan %p", chan);
3203 smp = chan->data;
3204 if (smp) {
3205 chan->data = NULL;
3206 crypto_free_skcipher(smp->tfm_aes);
3207 crypto_free_shash(smp->tfm_cmac);
3208 kzfree(smp);
3211 l2cap_chan_put(chan);
3214 static ssize_t force_bredr_smp_read(struct file *file,
3215 char __user *user_buf,
3216 size_t count, loff_t *ppos)
3218 struct hci_dev *hdev = file->private_data;
3219 char buf[3];
3221 buf[0] = hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP) ? 'Y': 'N';
3222 buf[1] = '\n';
3223 buf[2] = '\0';
3224 return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
3227 static ssize_t force_bredr_smp_write(struct file *file,
3228 const char __user *user_buf,
3229 size_t count, loff_t *ppos)
3231 struct hci_dev *hdev = file->private_data;
3232 char buf[32];
3233 size_t buf_size = min(count, (sizeof(buf)-1));
3234 bool enable;
3236 if (copy_from_user(buf, user_buf, buf_size))
3237 return -EFAULT;
3239 buf[buf_size] = '\0';
3240 if (strtobool(buf, &enable))
3241 return -EINVAL;
3243 if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3244 return -EALREADY;
3246 if (enable) {
3247 struct l2cap_chan *chan;
3249 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3250 if (IS_ERR(chan))
3251 return PTR_ERR(chan);
3253 hdev->smp_bredr_data = chan;
3254 } else {
3255 struct l2cap_chan *chan;
3257 chan = hdev->smp_bredr_data;
3258 hdev->smp_bredr_data = NULL;
3259 smp_del_chan(chan);
3262 hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP);
3264 return count;
3267 static const struct file_operations force_bredr_smp_fops = {
3268 .open = simple_open,
3269 .read = force_bredr_smp_read,
3270 .write = force_bredr_smp_write,
3271 .llseek = default_llseek,
3274 static ssize_t le_min_key_size_read(struct file *file,
3275 char __user *user_buf,
3276 size_t count, loff_t *ppos)
3278 struct hci_dev *hdev = file->private_data;
3279 char buf[4];
3281 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->min_key_size);
3283 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf));
3286 static ssize_t le_min_key_size_write(struct file *file,
3287 const char __user *user_buf,
3288 size_t count, loff_t *ppos)
3290 struct hci_dev *hdev = file->private_data;
3291 char buf[32];
3292 size_t buf_size = min(count, (sizeof(buf) - 1));
3293 u8 key_size;
3295 if (copy_from_user(buf, user_buf, buf_size))
3296 return -EFAULT;
3298 buf[buf_size] = '\0';
3300 sscanf(buf, "%hhu", &key_size);
3302 if (key_size > SMP_DEV(hdev)->max_key_size ||
3303 key_size < SMP_MIN_ENC_KEY_SIZE)
3304 return -EINVAL;
3306 SMP_DEV(hdev)->min_key_size = key_size;
3308 return count;
3311 static const struct file_operations le_min_key_size_fops = {
3312 .open = simple_open,
3313 .read = le_min_key_size_read,
3314 .write = le_min_key_size_write,
3315 .llseek = default_llseek,
3318 static ssize_t le_max_key_size_read(struct file *file,
3319 char __user *user_buf,
3320 size_t count, loff_t *ppos)
3322 struct hci_dev *hdev = file->private_data;
3323 char buf[4];
3325 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->max_key_size);
3327 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf));
3330 static ssize_t le_max_key_size_write(struct file *file,
3331 const char __user *user_buf,
3332 size_t count, loff_t *ppos)
3334 struct hci_dev *hdev = file->private_data;
3335 char buf[32];
3336 size_t buf_size = min(count, (sizeof(buf) - 1));
3337 u8 key_size;
3339 if (copy_from_user(buf, user_buf, buf_size))
3340 return -EFAULT;
3342 buf[buf_size] = '\0';
3344 sscanf(buf, "%hhu", &key_size);
3346 if (key_size > SMP_MAX_ENC_KEY_SIZE ||
3347 key_size < SMP_DEV(hdev)->min_key_size)
3348 return -EINVAL;
3350 SMP_DEV(hdev)->max_key_size = key_size;
3352 return count;
3355 static const struct file_operations le_max_key_size_fops = {
3356 .open = simple_open,
3357 .read = le_max_key_size_read,
3358 .write = le_max_key_size_write,
3359 .llseek = default_llseek,
3362 int smp_register(struct hci_dev *hdev)
3364 struct l2cap_chan *chan;
3366 BT_DBG("%s", hdev->name);
3368 /* If the controller does not support Low Energy operation, then
3369 * there is also no need to register any SMP channel.
3371 if (!lmp_le_capable(hdev))
3372 return 0;
3374 if (WARN_ON(hdev->smp_data)) {
3375 chan = hdev->smp_data;
3376 hdev->smp_data = NULL;
3377 smp_del_chan(chan);
3380 chan = smp_add_cid(hdev, L2CAP_CID_SMP);
3381 if (IS_ERR(chan))
3382 return PTR_ERR(chan);
3384 hdev->smp_data = chan;
3386 debugfs_create_file("le_min_key_size", 0644, hdev->debugfs, hdev,
3387 &le_min_key_size_fops);
3388 debugfs_create_file("le_max_key_size", 0644, hdev->debugfs, hdev,
3389 &le_max_key_size_fops);
3391 /* If the controller does not support BR/EDR Secure Connections
3392 * feature, then the BR/EDR SMP channel shall not be present.
3394 * To test this with Bluetooth 4.0 controllers, create a debugfs
3395 * switch that allows forcing BR/EDR SMP support and accepting
3396 * cross-transport pairing on non-AES encrypted connections.
3398 if (!lmp_sc_capable(hdev)) {
3399 debugfs_create_file("force_bredr_smp", 0644, hdev->debugfs,
3400 hdev, &force_bredr_smp_fops);
3401 return 0;
3404 if (WARN_ON(hdev->smp_bredr_data)) {
3405 chan = hdev->smp_bredr_data;
3406 hdev->smp_bredr_data = NULL;
3407 smp_del_chan(chan);
3410 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3411 if (IS_ERR(chan)) {
3412 int err = PTR_ERR(chan);
3413 chan = hdev->smp_data;
3414 hdev->smp_data = NULL;
3415 smp_del_chan(chan);
3416 return err;
3419 hdev->smp_bredr_data = chan;
3421 return 0;
3424 void smp_unregister(struct hci_dev *hdev)
3426 struct l2cap_chan *chan;
3428 if (hdev->smp_bredr_data) {
3429 chan = hdev->smp_bredr_data;
3430 hdev->smp_bredr_data = NULL;
3431 smp_del_chan(chan);
3434 if (hdev->smp_data) {
3435 chan = hdev->smp_data;
3436 hdev->smp_data = NULL;
3437 smp_del_chan(chan);
3441 #if IS_ENABLED(CONFIG_BT_SELFTEST_SMP)
3443 static int __init test_ah(struct crypto_skcipher *tfm_aes)
3445 const u8 irk[16] = {
3446 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3447 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3448 const u8 r[3] = { 0x94, 0x81, 0x70 };
3449 const u8 exp[3] = { 0xaa, 0xfb, 0x0d };
3450 u8 res[3];
3451 int err;
3453 err = smp_ah(tfm_aes, irk, r, res);
3454 if (err)
3455 return err;
3457 if (memcmp(res, exp, 3))
3458 return -EINVAL;
3460 return 0;
3463 static int __init test_c1(struct crypto_skcipher *tfm_aes)
3465 const u8 k[16] = {
3466 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
3467 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
3468 const u8 r[16] = {
3469 0xe0, 0x2e, 0x70, 0xc6, 0x4e, 0x27, 0x88, 0x63,
3470 0x0e, 0x6f, 0xad, 0x56, 0x21, 0xd5, 0x83, 0x57 };
3471 const u8 preq[7] = { 0x01, 0x01, 0x00, 0x00, 0x10, 0x07, 0x07 };
3472 const u8 pres[7] = { 0x02, 0x03, 0x00, 0x00, 0x08, 0x00, 0x05 };
3473 const u8 _iat = 0x01;
3474 const u8 _rat = 0x00;
3475 const bdaddr_t ra = { { 0xb6, 0xb5, 0xb4, 0xb3, 0xb2, 0xb1 } };
3476 const bdaddr_t ia = { { 0xa6, 0xa5, 0xa4, 0xa3, 0xa2, 0xa1 } };
3477 const u8 exp[16] = {
3478 0x86, 0x3b, 0xf1, 0xbe, 0xc5, 0x4d, 0xa7, 0xd2,
3479 0xea, 0x88, 0x89, 0x87, 0xef, 0x3f, 0x1e, 0x1e };
3480 u8 res[16];
3481 int err;
3483 err = smp_c1(tfm_aes, k, r, preq, pres, _iat, &ia, _rat, &ra, res);
3484 if (err)
3485 return err;
3487 if (memcmp(res, exp, 16))
3488 return -EINVAL;
3490 return 0;
3493 static int __init test_s1(struct crypto_skcipher *tfm_aes)
3495 const u8 k[16] = {
3496 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
3497 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
3498 const u8 r1[16] = {
3499 0x88, 0x77, 0x66, 0x55, 0x44, 0x33, 0x22, 0x11 };
3500 const u8 r2[16] = {
3501 0x00, 0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa, 0x99 };
3502 const u8 exp[16] = {
3503 0x62, 0xa0, 0x6d, 0x79, 0xae, 0x16, 0x42, 0x5b,
3504 0x9b, 0xf4, 0xb0, 0xe8, 0xf0, 0xe1, 0x1f, 0x9a };
3505 u8 res[16];
3506 int err;
3508 err = smp_s1(tfm_aes, k, r1, r2, res);
3509 if (err)
3510 return err;
3512 if (memcmp(res, exp, 16))
3513 return -EINVAL;
3515 return 0;
3518 static int __init test_f4(struct crypto_shash *tfm_cmac)
3520 const u8 u[32] = {
3521 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
3522 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
3523 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
3524 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 };
3525 const u8 v[32] = {
3526 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b,
3527 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59,
3528 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90,
3529 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 };
3530 const u8 x[16] = {
3531 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3532 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3533 const u8 z = 0x00;
3534 const u8 exp[16] = {
3535 0x2d, 0x87, 0x74, 0xa9, 0xbe, 0xa1, 0xed, 0xf1,
3536 0x1c, 0xbd, 0xa9, 0x07, 0xf1, 0x16, 0xc9, 0xf2 };
3537 u8 res[16];
3538 int err;
3540 err = smp_f4(tfm_cmac, u, v, x, z, res);
3541 if (err)
3542 return err;
3544 if (memcmp(res, exp, 16))
3545 return -EINVAL;
3547 return 0;
3550 static int __init test_f5(struct crypto_shash *tfm_cmac)
3552 const u8 w[32] = {
3553 0x98, 0xa6, 0xbf, 0x73, 0xf3, 0x34, 0x8d, 0x86,
3554 0xf1, 0x66, 0xf8, 0xb4, 0x13, 0x6b, 0x79, 0x99,
3555 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3556 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3557 const u8 n1[16] = {
3558 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3559 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3560 const u8 n2[16] = {
3561 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3562 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3563 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 };
3564 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 };
3565 const u8 exp_ltk[16] = {
3566 0x38, 0x0a, 0x75, 0x94, 0xb5, 0x22, 0x05, 0x98,
3567 0x23, 0xcd, 0xd7, 0x69, 0x11, 0x79, 0x86, 0x69 };
3568 const u8 exp_mackey[16] = {
3569 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd,
3570 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 };
3571 u8 mackey[16], ltk[16];
3572 int err;
3574 err = smp_f5(tfm_cmac, w, n1, n2, a1, a2, mackey, ltk);
3575 if (err)
3576 return err;
3578 if (memcmp(mackey, exp_mackey, 16))
3579 return -EINVAL;
3581 if (memcmp(ltk, exp_ltk, 16))
3582 return -EINVAL;
3584 return 0;
3587 static int __init test_f6(struct crypto_shash *tfm_cmac)
3589 const u8 w[16] = {
3590 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd,
3591 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 };
3592 const u8 n1[16] = {
3593 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3594 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3595 const u8 n2[16] = {
3596 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3597 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3598 const u8 r[16] = {
3599 0xc8, 0x0f, 0x2d, 0x0c, 0xd2, 0x42, 0xda, 0x08,
3600 0x54, 0xbb, 0x53, 0xb4, 0x3b, 0x34, 0xa3, 0x12 };
3601 const u8 io_cap[3] = { 0x02, 0x01, 0x01 };
3602 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 };
3603 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 };
3604 const u8 exp[16] = {
3605 0x61, 0x8f, 0x95, 0xda, 0x09, 0x0b, 0x6c, 0xd2,
3606 0xc5, 0xe8, 0xd0, 0x9c, 0x98, 0x73, 0xc4, 0xe3 };
3607 u8 res[16];
3608 int err;
3610 err = smp_f6(tfm_cmac, w, n1, n2, r, io_cap, a1, a2, res);
3611 if (err)
3612 return err;
3614 if (memcmp(res, exp, 16))
3615 return -EINVAL;
3617 return 0;
3620 static int __init test_g2(struct crypto_shash *tfm_cmac)
3622 const u8 u[32] = {
3623 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
3624 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
3625 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
3626 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 };
3627 const u8 v[32] = {
3628 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b,
3629 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59,
3630 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90,
3631 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 };
3632 const u8 x[16] = {
3633 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3634 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3635 const u8 y[16] = {
3636 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3637 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3638 const u32 exp_val = 0x2f9ed5ba % 1000000;
3639 u32 val;
3640 int err;
3642 err = smp_g2(tfm_cmac, u, v, x, y, &val);
3643 if (err)
3644 return err;
3646 if (val != exp_val)
3647 return -EINVAL;
3649 return 0;
3652 static int __init test_h6(struct crypto_shash *tfm_cmac)
3654 const u8 w[16] = {
3655 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3656 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3657 const u8 key_id[4] = { 0x72, 0x62, 0x65, 0x6c };
3658 const u8 exp[16] = {
3659 0x99, 0x63, 0xb1, 0x80, 0xe2, 0xa9, 0xd3, 0xe8,
3660 0x1c, 0xc9, 0x6d, 0xe7, 0x02, 0xe1, 0x9a, 0x2d };
3661 u8 res[16];
3662 int err;
3664 err = smp_h6(tfm_cmac, w, key_id, res);
3665 if (err)
3666 return err;
3668 if (memcmp(res, exp, 16))
3669 return -EINVAL;
3671 return 0;
3674 static char test_smp_buffer[32];
3676 static ssize_t test_smp_read(struct file *file, char __user *user_buf,
3677 size_t count, loff_t *ppos)
3679 return simple_read_from_buffer(user_buf, count, ppos, test_smp_buffer,
3680 strlen(test_smp_buffer));
3683 static const struct file_operations test_smp_fops = {
3684 .open = simple_open,
3685 .read = test_smp_read,
3686 .llseek = default_llseek,
3689 static int __init run_selftests(struct crypto_skcipher *tfm_aes,
3690 struct crypto_shash *tfm_cmac)
3692 ktime_t calltime, delta, rettime;
3693 unsigned long long duration;
3694 int err;
3696 calltime = ktime_get();
3698 err = test_ah(tfm_aes);
3699 if (err) {
3700 BT_ERR("smp_ah test failed");
3701 goto done;
3704 err = test_c1(tfm_aes);
3705 if (err) {
3706 BT_ERR("smp_c1 test failed");
3707 goto done;
3710 err = test_s1(tfm_aes);
3711 if (err) {
3712 BT_ERR("smp_s1 test failed");
3713 goto done;
3716 err = test_f4(tfm_cmac);
3717 if (err) {
3718 BT_ERR("smp_f4 test failed");
3719 goto done;
3722 err = test_f5(tfm_cmac);
3723 if (err) {
3724 BT_ERR("smp_f5 test failed");
3725 goto done;
3728 err = test_f6(tfm_cmac);
3729 if (err) {
3730 BT_ERR("smp_f6 test failed");
3731 goto done;
3734 err = test_g2(tfm_cmac);
3735 if (err) {
3736 BT_ERR("smp_g2 test failed");
3737 goto done;
3740 err = test_h6(tfm_cmac);
3741 if (err) {
3742 BT_ERR("smp_h6 test failed");
3743 goto done;
3746 rettime = ktime_get();
3747 delta = ktime_sub(rettime, calltime);
3748 duration = (unsigned long long) ktime_to_ns(delta) >> 10;
3750 BT_INFO("SMP test passed in %llu usecs", duration);
3752 done:
3753 if (!err)
3754 snprintf(test_smp_buffer, sizeof(test_smp_buffer),
3755 "PASS (%llu usecs)\n", duration);
3756 else
3757 snprintf(test_smp_buffer, sizeof(test_smp_buffer), "FAIL\n");
3759 debugfs_create_file("selftest_smp", 0444, bt_debugfs, NULL,
3760 &test_smp_fops);
3762 return err;
3765 int __init bt_selftest_smp(void)
3767 struct crypto_skcipher *tfm_aes;
3768 struct crypto_shash *tfm_cmac;
3769 int err;
3771 tfm_aes = crypto_alloc_skcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
3772 if (IS_ERR(tfm_aes)) {
3773 BT_ERR("Unable to create ECB crypto context");
3774 return PTR_ERR(tfm_aes);
3777 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, CRYPTO_ALG_ASYNC);
3778 if (IS_ERR(tfm_cmac)) {
3779 BT_ERR("Unable to create CMAC crypto context");
3780 crypto_free_skcipher(tfm_aes);
3781 return PTR_ERR(tfm_cmac);
3784 err = run_selftests(tfm_aes, tfm_cmac);
3786 crypto_free_shash(tfm_cmac);
3787 crypto_free_skcipher(tfm_aes);
3789 return err;
3792 #endif