net/mlx5e: Single bfreg (UAR) for all mlx5e SQs and netdevs
[linux-2.6/btrfs-unstable.git] / net / bluetooth / smp.c
blobfae391f1871f138c802722d8d8d86d817a97947e
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 <linux/crypto.h>
26 #include <crypto/b128ops.h>
27 #include <crypto/hash.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 0x3f : 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,
79 SMP_FLAG_CT2,
82 struct smp_dev {
83 /* Secure Connections OOB data */
84 u8 local_pk[64];
85 u8 local_sk[32];
86 u8 local_rand[16];
87 bool debug_key;
89 u8 min_key_size;
90 u8 max_key_size;
92 struct crypto_cipher *tfm_aes;
93 struct crypto_shash *tfm_cmac;
96 struct smp_chan {
97 struct l2cap_conn *conn;
98 struct delayed_work security_timer;
99 unsigned long allow_cmd; /* Bitmask of allowed commands */
101 u8 preq[7]; /* SMP Pairing Request */
102 u8 prsp[7]; /* SMP Pairing Response */
103 u8 prnd[16]; /* SMP Pairing Random (local) */
104 u8 rrnd[16]; /* SMP Pairing Random (remote) */
105 u8 pcnf[16]; /* SMP Pairing Confirm */
106 u8 tk[16]; /* SMP Temporary Key */
107 u8 rr[16]; /* Remote OOB ra/rb value */
108 u8 lr[16]; /* Local OOB ra/rb value */
109 u8 enc_key_size;
110 u8 remote_key_dist;
111 bdaddr_t id_addr;
112 u8 id_addr_type;
113 u8 irk[16];
114 struct smp_csrk *csrk;
115 struct smp_csrk *slave_csrk;
116 struct smp_ltk *ltk;
117 struct smp_ltk *slave_ltk;
118 struct smp_irk *remote_irk;
119 u8 *link_key;
120 unsigned long flags;
121 u8 method;
122 u8 passkey_round;
124 /* Secure Connections variables */
125 u8 local_pk[64];
126 u8 local_sk[32];
127 u8 remote_pk[64];
128 u8 dhkey[32];
129 u8 mackey[16];
131 struct crypto_cipher *tfm_aes;
132 struct crypto_shash *tfm_cmac;
135 /* These debug key values are defined in the SMP section of the core
136 * specification. debug_pk is the public debug key and debug_sk the
137 * private debug key.
139 static const u8 debug_pk[64] = {
140 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
141 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
142 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
143 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20,
145 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74,
146 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76,
147 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63,
148 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc,
151 static const u8 debug_sk[32] = {
152 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58,
153 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a,
154 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74,
155 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f,
158 static inline void swap_buf(const u8 *src, u8 *dst, size_t len)
160 size_t i;
162 for (i = 0; i < len; i++)
163 dst[len - 1 - i] = src[i];
166 /* The following functions map to the LE SC SMP crypto functions
167 * AES-CMAC, f4, f5, f6, g2 and h6.
170 static int aes_cmac(struct crypto_shash *tfm, const u8 k[16], const u8 *m,
171 size_t len, u8 mac[16])
173 uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX];
174 SHASH_DESC_ON_STACK(desc, tfm);
175 int err;
177 if (len > CMAC_MSG_MAX)
178 return -EFBIG;
180 if (!tfm) {
181 BT_ERR("tfm %p", tfm);
182 return -EINVAL;
185 desc->tfm = tfm;
186 desc->flags = 0;
188 /* Swap key and message from LSB to MSB */
189 swap_buf(k, tmp, 16);
190 swap_buf(m, msg_msb, len);
192 SMP_DBG("msg (len %zu) %*phN", len, (int) len, m);
193 SMP_DBG("key %16phN", k);
195 err = crypto_shash_setkey(tfm, tmp, 16);
196 if (err) {
197 BT_ERR("cipher setkey failed: %d", err);
198 return err;
201 err = crypto_shash_digest(desc, msg_msb, len, mac_msb);
202 shash_desc_zero(desc);
203 if (err) {
204 BT_ERR("Hash computation error %d", err);
205 return err;
208 swap_buf(mac_msb, mac, 16);
210 SMP_DBG("mac %16phN", mac);
212 return 0;
215 static int smp_f4(struct crypto_shash *tfm_cmac, const u8 u[32],
216 const u8 v[32], const u8 x[16], u8 z, u8 res[16])
218 u8 m[65];
219 int err;
221 SMP_DBG("u %32phN", u);
222 SMP_DBG("v %32phN", v);
223 SMP_DBG("x %16phN z %02x", x, z);
225 m[0] = z;
226 memcpy(m + 1, v, 32);
227 memcpy(m + 33, u, 32);
229 err = aes_cmac(tfm_cmac, x, m, sizeof(m), res);
230 if (err)
231 return err;
233 SMP_DBG("res %16phN", res);
235 return err;
238 static int smp_f5(struct crypto_shash *tfm_cmac, const u8 w[32],
239 const u8 n1[16], const u8 n2[16], const u8 a1[7],
240 const u8 a2[7], u8 mackey[16], u8 ltk[16])
242 /* The btle, salt and length "magic" values are as defined in
243 * the SMP section of the Bluetooth core specification. In ASCII
244 * the btle value ends up being 'btle'. The salt is just a
245 * random number whereas length is the value 256 in little
246 * endian format.
248 const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 };
249 const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60,
250 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c };
251 const u8 length[2] = { 0x00, 0x01 };
252 u8 m[53], t[16];
253 int err;
255 SMP_DBG("w %32phN", w);
256 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
257 SMP_DBG("a1 %7phN a2 %7phN", a1, a2);
259 err = aes_cmac(tfm_cmac, salt, w, 32, t);
260 if (err)
261 return err;
263 SMP_DBG("t %16phN", t);
265 memcpy(m, length, 2);
266 memcpy(m + 2, a2, 7);
267 memcpy(m + 9, a1, 7);
268 memcpy(m + 16, n2, 16);
269 memcpy(m + 32, n1, 16);
270 memcpy(m + 48, btle, 4);
272 m[52] = 0; /* Counter */
274 err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey);
275 if (err)
276 return err;
278 SMP_DBG("mackey %16phN", mackey);
280 m[52] = 1; /* Counter */
282 err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk);
283 if (err)
284 return err;
286 SMP_DBG("ltk %16phN", ltk);
288 return 0;
291 static int smp_f6(struct crypto_shash *tfm_cmac, const u8 w[16],
292 const u8 n1[16], const u8 n2[16], const u8 r[16],
293 const u8 io_cap[3], const u8 a1[7], const u8 a2[7],
294 u8 res[16])
296 u8 m[65];
297 int err;
299 SMP_DBG("w %16phN", w);
300 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
301 SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2);
303 memcpy(m, a2, 7);
304 memcpy(m + 7, a1, 7);
305 memcpy(m + 14, io_cap, 3);
306 memcpy(m + 17, r, 16);
307 memcpy(m + 33, n2, 16);
308 memcpy(m + 49, n1, 16);
310 err = aes_cmac(tfm_cmac, w, m, sizeof(m), res);
311 if (err)
312 return err;
314 SMP_DBG("res %16phN", res);
316 return err;
319 static int smp_g2(struct crypto_shash *tfm_cmac, const u8 u[32], const u8 v[32],
320 const u8 x[16], const u8 y[16], u32 *val)
322 u8 m[80], tmp[16];
323 int err;
325 SMP_DBG("u %32phN", u);
326 SMP_DBG("v %32phN", v);
327 SMP_DBG("x %16phN y %16phN", x, y);
329 memcpy(m, y, 16);
330 memcpy(m + 16, v, 32);
331 memcpy(m + 48, u, 32);
333 err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp);
334 if (err)
335 return err;
337 *val = get_unaligned_le32(tmp);
338 *val %= 1000000;
340 SMP_DBG("val %06u", *val);
342 return 0;
345 static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16],
346 const u8 key_id[4], u8 res[16])
348 int err;
350 SMP_DBG("w %16phN key_id %4phN", w, key_id);
352 err = aes_cmac(tfm_cmac, w, key_id, 4, res);
353 if (err)
354 return err;
356 SMP_DBG("res %16phN", res);
358 return err;
361 static int smp_h7(struct crypto_shash *tfm_cmac, const u8 w[16],
362 const u8 salt[16], u8 res[16])
364 int err;
366 SMP_DBG("w %16phN salt %16phN", w, salt);
368 err = aes_cmac(tfm_cmac, salt, w, 16, res);
369 if (err)
370 return err;
372 SMP_DBG("res %16phN", res);
374 return err;
377 /* The following functions map to the legacy SMP crypto functions e, c1,
378 * s1 and ah.
381 static int smp_e(struct crypto_cipher *tfm, const u8 *k, u8 *r)
383 uint8_t tmp[16], data[16];
384 int err;
386 SMP_DBG("k %16phN r %16phN", k, r);
388 if (!tfm) {
389 BT_ERR("tfm %p", tfm);
390 return -EINVAL;
393 /* The most significant octet of key corresponds to k[0] */
394 swap_buf(k, tmp, 16);
396 err = crypto_cipher_setkey(tfm, tmp, 16);
397 if (err) {
398 BT_ERR("cipher setkey failed: %d", err);
399 return err;
402 /* Most significant octet of plaintextData corresponds to data[0] */
403 swap_buf(r, data, 16);
405 crypto_cipher_encrypt_one(tfm, data, data);
407 /* Most significant octet of encryptedData corresponds to data[0] */
408 swap_buf(data, r, 16);
410 SMP_DBG("r %16phN", r);
412 return err;
415 static int smp_c1(struct crypto_cipher *tfm_aes, const u8 k[16],
416 const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat,
417 const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16])
419 u8 p1[16], p2[16];
420 int err;
422 SMP_DBG("k %16phN r %16phN", k, r);
423 SMP_DBG("iat %u ia %6phN rat %u ra %6phN", _iat, ia, _rat, ra);
424 SMP_DBG("preq %7phN pres %7phN", preq, pres);
426 memset(p1, 0, 16);
428 /* p1 = pres || preq || _rat || _iat */
429 p1[0] = _iat;
430 p1[1] = _rat;
431 memcpy(p1 + 2, preq, 7);
432 memcpy(p1 + 9, pres, 7);
434 SMP_DBG("p1 %16phN", p1);
436 /* res = r XOR p1 */
437 u128_xor((u128 *) res, (u128 *) r, (u128 *) p1);
439 /* res = e(k, res) */
440 err = smp_e(tfm_aes, k, res);
441 if (err) {
442 BT_ERR("Encrypt data error");
443 return err;
446 /* p2 = padding || ia || ra */
447 memcpy(p2, ra, 6);
448 memcpy(p2 + 6, ia, 6);
449 memset(p2 + 12, 0, 4);
451 SMP_DBG("p2 %16phN", p2);
453 /* res = res XOR p2 */
454 u128_xor((u128 *) res, (u128 *) res, (u128 *) p2);
456 /* res = e(k, res) */
457 err = smp_e(tfm_aes, k, res);
458 if (err)
459 BT_ERR("Encrypt data error");
461 return err;
464 static int smp_s1(struct crypto_cipher *tfm_aes, const u8 k[16],
465 const u8 r1[16], const u8 r2[16], u8 _r[16])
467 int err;
469 /* Just least significant octets from r1 and r2 are considered */
470 memcpy(_r, r2, 8);
471 memcpy(_r + 8, r1, 8);
473 err = smp_e(tfm_aes, k, _r);
474 if (err)
475 BT_ERR("Encrypt data error");
477 return err;
480 static int smp_ah(struct crypto_cipher *tfm, const u8 irk[16],
481 const u8 r[3], u8 res[3])
483 u8 _res[16];
484 int err;
486 /* r' = padding || r */
487 memcpy(_res, r, 3);
488 memset(_res + 3, 0, 13);
490 err = smp_e(tfm, irk, _res);
491 if (err) {
492 BT_ERR("Encrypt error");
493 return err;
496 /* The output of the random address function ah is:
497 * ah(k, r) = e(k, r') mod 2^24
498 * The output of the security function e is then truncated to 24 bits
499 * by taking the least significant 24 bits of the output of e as the
500 * result of ah.
502 memcpy(res, _res, 3);
504 return 0;
507 bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16],
508 const bdaddr_t *bdaddr)
510 struct l2cap_chan *chan = hdev->smp_data;
511 struct smp_dev *smp;
512 u8 hash[3];
513 int err;
515 if (!chan || !chan->data)
516 return false;
518 smp = chan->data;
520 BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk);
522 err = smp_ah(smp->tfm_aes, irk, &bdaddr->b[3], hash);
523 if (err)
524 return false;
526 return !memcmp(bdaddr->b, hash, 3);
529 int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa)
531 struct l2cap_chan *chan = hdev->smp_data;
532 struct smp_dev *smp;
533 int err;
535 if (!chan || !chan->data)
536 return -EOPNOTSUPP;
538 smp = chan->data;
540 get_random_bytes(&rpa->b[3], 3);
542 rpa->b[5] &= 0x3f; /* Clear two most significant bits */
543 rpa->b[5] |= 0x40; /* Set second most significant bit */
545 err = smp_ah(smp->tfm_aes, irk, &rpa->b[3], rpa->b);
546 if (err < 0)
547 return err;
549 BT_DBG("RPA %pMR", rpa);
551 return 0;
554 int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16])
556 struct l2cap_chan *chan = hdev->smp_data;
557 struct smp_dev *smp;
558 int err;
560 if (!chan || !chan->data)
561 return -EOPNOTSUPP;
563 smp = chan->data;
565 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
566 BT_DBG("Using debug keys");
567 memcpy(smp->local_pk, debug_pk, 64);
568 memcpy(smp->local_sk, debug_sk, 32);
569 smp->debug_key = true;
570 } else {
571 while (true) {
572 /* Generate local key pair for Secure Connections */
573 if (!ecc_make_key(smp->local_pk, smp->local_sk))
574 return -EIO;
576 /* This is unlikely, but we need to check that
577 * we didn't accidentially generate a debug key.
579 if (memcmp(smp->local_sk, debug_sk, 32))
580 break;
582 smp->debug_key = false;
585 SMP_DBG("OOB Public Key X: %32phN", smp->local_pk);
586 SMP_DBG("OOB Public Key Y: %32phN", smp->local_pk + 32);
587 SMP_DBG("OOB Private Key: %32phN", smp->local_sk);
589 get_random_bytes(smp->local_rand, 16);
591 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->local_pk,
592 smp->local_rand, 0, hash);
593 if (err < 0)
594 return err;
596 memcpy(rand, smp->local_rand, 16);
598 return 0;
601 static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
603 struct l2cap_chan *chan = conn->smp;
604 struct smp_chan *smp;
605 struct kvec iv[2];
606 struct msghdr msg;
608 if (!chan)
609 return;
611 BT_DBG("code 0x%2.2x", code);
613 iv[0].iov_base = &code;
614 iv[0].iov_len = 1;
616 iv[1].iov_base = data;
617 iv[1].iov_len = len;
619 memset(&msg, 0, sizeof(msg));
621 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iv, 2, 1 + len);
623 l2cap_chan_send(chan, &msg, 1 + len);
625 if (!chan->data)
626 return;
628 smp = chan->data;
630 cancel_delayed_work_sync(&smp->security_timer);
631 schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT);
634 static u8 authreq_to_seclevel(u8 authreq)
636 if (authreq & SMP_AUTH_MITM) {
637 if (authreq & SMP_AUTH_SC)
638 return BT_SECURITY_FIPS;
639 else
640 return BT_SECURITY_HIGH;
641 } else {
642 return BT_SECURITY_MEDIUM;
646 static __u8 seclevel_to_authreq(__u8 sec_level)
648 switch (sec_level) {
649 case BT_SECURITY_FIPS:
650 case BT_SECURITY_HIGH:
651 return SMP_AUTH_MITM | SMP_AUTH_BONDING;
652 case BT_SECURITY_MEDIUM:
653 return SMP_AUTH_BONDING;
654 default:
655 return SMP_AUTH_NONE;
659 static void build_pairing_cmd(struct l2cap_conn *conn,
660 struct smp_cmd_pairing *req,
661 struct smp_cmd_pairing *rsp, __u8 authreq)
663 struct l2cap_chan *chan = conn->smp;
664 struct smp_chan *smp = chan->data;
665 struct hci_conn *hcon = conn->hcon;
666 struct hci_dev *hdev = hcon->hdev;
667 u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT;
669 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
670 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
671 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
672 authreq |= SMP_AUTH_BONDING;
673 } else {
674 authreq &= ~SMP_AUTH_BONDING;
677 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
678 remote_dist |= SMP_DIST_ID_KEY;
680 if (hci_dev_test_flag(hdev, HCI_PRIVACY))
681 local_dist |= SMP_DIST_ID_KEY;
683 if (hci_dev_test_flag(hdev, HCI_SC_ENABLED) &&
684 (authreq & SMP_AUTH_SC)) {
685 struct oob_data *oob_data;
686 u8 bdaddr_type;
688 if (hci_dev_test_flag(hdev, HCI_SSP_ENABLED)) {
689 local_dist |= SMP_DIST_LINK_KEY;
690 remote_dist |= SMP_DIST_LINK_KEY;
693 if (hcon->dst_type == ADDR_LE_DEV_PUBLIC)
694 bdaddr_type = BDADDR_LE_PUBLIC;
695 else
696 bdaddr_type = BDADDR_LE_RANDOM;
698 oob_data = hci_find_remote_oob_data(hdev, &hcon->dst,
699 bdaddr_type);
700 if (oob_data && oob_data->present) {
701 set_bit(SMP_FLAG_REMOTE_OOB, &smp->flags);
702 oob_flag = SMP_OOB_PRESENT;
703 memcpy(smp->rr, oob_data->rand256, 16);
704 memcpy(smp->pcnf, oob_data->hash256, 16);
705 SMP_DBG("OOB Remote Confirmation: %16phN", smp->pcnf);
706 SMP_DBG("OOB Remote Random: %16phN", smp->rr);
709 } else {
710 authreq &= ~SMP_AUTH_SC;
713 if (rsp == NULL) {
714 req->io_capability = conn->hcon->io_capability;
715 req->oob_flag = oob_flag;
716 req->max_key_size = SMP_DEV(hdev)->max_key_size;
717 req->init_key_dist = local_dist;
718 req->resp_key_dist = remote_dist;
719 req->auth_req = (authreq & AUTH_REQ_MASK(hdev));
721 smp->remote_key_dist = remote_dist;
722 return;
725 rsp->io_capability = conn->hcon->io_capability;
726 rsp->oob_flag = oob_flag;
727 rsp->max_key_size = SMP_DEV(hdev)->max_key_size;
728 rsp->init_key_dist = req->init_key_dist & remote_dist;
729 rsp->resp_key_dist = req->resp_key_dist & local_dist;
730 rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev));
732 smp->remote_key_dist = rsp->init_key_dist;
735 static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)
737 struct l2cap_chan *chan = conn->smp;
738 struct hci_dev *hdev = conn->hcon->hdev;
739 struct smp_chan *smp = chan->data;
741 if (max_key_size > SMP_DEV(hdev)->max_key_size ||
742 max_key_size < SMP_MIN_ENC_KEY_SIZE)
743 return SMP_ENC_KEY_SIZE;
745 smp->enc_key_size = max_key_size;
747 return 0;
750 static void smp_chan_destroy(struct l2cap_conn *conn)
752 struct l2cap_chan *chan = conn->smp;
753 struct smp_chan *smp = chan->data;
754 struct hci_conn *hcon = conn->hcon;
755 bool complete;
757 BUG_ON(!smp);
759 cancel_delayed_work_sync(&smp->security_timer);
761 complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags);
762 mgmt_smp_complete(hcon, complete);
764 kzfree(smp->csrk);
765 kzfree(smp->slave_csrk);
766 kzfree(smp->link_key);
768 crypto_free_cipher(smp->tfm_aes);
769 crypto_free_shash(smp->tfm_cmac);
771 /* Ensure that we don't leave any debug key around if debug key
772 * support hasn't been explicitly enabled.
774 if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG &&
775 !hci_dev_test_flag(hcon->hdev, HCI_KEEP_DEBUG_KEYS)) {
776 list_del_rcu(&smp->ltk->list);
777 kfree_rcu(smp->ltk, rcu);
778 smp->ltk = NULL;
781 /* If pairing failed clean up any keys we might have */
782 if (!complete) {
783 if (smp->ltk) {
784 list_del_rcu(&smp->ltk->list);
785 kfree_rcu(smp->ltk, rcu);
788 if (smp->slave_ltk) {
789 list_del_rcu(&smp->slave_ltk->list);
790 kfree_rcu(smp->slave_ltk, rcu);
793 if (smp->remote_irk) {
794 list_del_rcu(&smp->remote_irk->list);
795 kfree_rcu(smp->remote_irk, rcu);
799 chan->data = NULL;
800 kzfree(smp);
801 hci_conn_drop(hcon);
804 static void smp_failure(struct l2cap_conn *conn, u8 reason)
806 struct hci_conn *hcon = conn->hcon;
807 struct l2cap_chan *chan = conn->smp;
809 if (reason)
810 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
811 &reason);
813 mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE);
815 if (chan->data)
816 smp_chan_destroy(conn);
819 #define JUST_WORKS 0x00
820 #define JUST_CFM 0x01
821 #define REQ_PASSKEY 0x02
822 #define CFM_PASSKEY 0x03
823 #define REQ_OOB 0x04
824 #define DSP_PASSKEY 0x05
825 #define OVERLAP 0xFF
827 static const u8 gen_method[5][5] = {
828 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
829 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
830 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
831 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
832 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP },
835 static const u8 sc_method[5][5] = {
836 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
837 { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
838 { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY },
839 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
840 { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
843 static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io)
845 /* If either side has unknown io_caps, use JUST_CFM (which gets
846 * converted later to JUST_WORKS if we're initiators.
848 if (local_io > SMP_IO_KEYBOARD_DISPLAY ||
849 remote_io > SMP_IO_KEYBOARD_DISPLAY)
850 return JUST_CFM;
852 if (test_bit(SMP_FLAG_SC, &smp->flags))
853 return sc_method[remote_io][local_io];
855 return gen_method[remote_io][local_io];
858 static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
859 u8 local_io, u8 remote_io)
861 struct hci_conn *hcon = conn->hcon;
862 struct l2cap_chan *chan = conn->smp;
863 struct smp_chan *smp = chan->data;
864 u32 passkey = 0;
865 int ret = 0;
867 /* Initialize key for JUST WORKS */
868 memset(smp->tk, 0, sizeof(smp->tk));
869 clear_bit(SMP_FLAG_TK_VALID, &smp->flags);
871 BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io);
873 /* If neither side wants MITM, either "just" confirm an incoming
874 * request or use just-works for outgoing ones. The JUST_CFM
875 * will be converted to JUST_WORKS if necessary later in this
876 * function. If either side has MITM look up the method from the
877 * table.
879 if (!(auth & SMP_AUTH_MITM))
880 smp->method = JUST_CFM;
881 else
882 smp->method = get_auth_method(smp, local_io, remote_io);
884 /* Don't confirm locally initiated pairing attempts */
885 if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR,
886 &smp->flags))
887 smp->method = JUST_WORKS;
889 /* Don't bother user space with no IO capabilities */
890 if (smp->method == JUST_CFM &&
891 hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
892 smp->method = JUST_WORKS;
894 /* If Just Works, Continue with Zero TK */
895 if (smp->method == JUST_WORKS) {
896 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
897 return 0;
900 /* If this function is used for SC -> legacy fallback we
901 * can only recover the just-works case.
903 if (test_bit(SMP_FLAG_SC, &smp->flags))
904 return -EINVAL;
906 /* Not Just Works/Confirm results in MITM Authentication */
907 if (smp->method != JUST_CFM) {
908 set_bit(SMP_FLAG_MITM_AUTH, &smp->flags);
909 if (hcon->pending_sec_level < BT_SECURITY_HIGH)
910 hcon->pending_sec_level = BT_SECURITY_HIGH;
913 /* If both devices have Keyoard-Display I/O, the master
914 * Confirms and the slave Enters the passkey.
916 if (smp->method == OVERLAP) {
917 if (hcon->role == HCI_ROLE_MASTER)
918 smp->method = CFM_PASSKEY;
919 else
920 smp->method = REQ_PASSKEY;
923 /* Generate random passkey. */
924 if (smp->method == CFM_PASSKEY) {
925 memset(smp->tk, 0, sizeof(smp->tk));
926 get_random_bytes(&passkey, sizeof(passkey));
927 passkey %= 1000000;
928 put_unaligned_le32(passkey, smp->tk);
929 BT_DBG("PassKey: %d", passkey);
930 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
933 if (smp->method == REQ_PASSKEY)
934 ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst,
935 hcon->type, hcon->dst_type);
936 else if (smp->method == JUST_CFM)
937 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
938 hcon->type, hcon->dst_type,
939 passkey, 1);
940 else
941 ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst,
942 hcon->type, hcon->dst_type,
943 passkey, 0);
945 return ret;
948 static u8 smp_confirm(struct smp_chan *smp)
950 struct l2cap_conn *conn = smp->conn;
951 struct smp_cmd_pairing_confirm cp;
952 int ret;
954 BT_DBG("conn %p", conn);
956 ret = smp_c1(smp->tfm_aes, smp->tk, smp->prnd, smp->preq, smp->prsp,
957 conn->hcon->init_addr_type, &conn->hcon->init_addr,
958 conn->hcon->resp_addr_type, &conn->hcon->resp_addr,
959 cp.confirm_val);
960 if (ret)
961 return SMP_UNSPECIFIED;
963 clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
965 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
967 if (conn->hcon->out)
968 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
969 else
970 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
972 return 0;
975 static u8 smp_random(struct smp_chan *smp)
977 struct l2cap_conn *conn = smp->conn;
978 struct hci_conn *hcon = conn->hcon;
979 u8 confirm[16];
980 int ret;
982 if (IS_ERR_OR_NULL(smp->tfm_aes))
983 return SMP_UNSPECIFIED;
985 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
987 ret = smp_c1(smp->tfm_aes, smp->tk, smp->rrnd, smp->preq, smp->prsp,
988 hcon->init_addr_type, &hcon->init_addr,
989 hcon->resp_addr_type, &hcon->resp_addr, confirm);
990 if (ret)
991 return SMP_UNSPECIFIED;
993 if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) {
994 BT_ERR("Pairing failed (confirmation values mismatch)");
995 return SMP_CONFIRM_FAILED;
998 if (hcon->out) {
999 u8 stk[16];
1000 __le64 rand = 0;
1001 __le16 ediv = 0;
1003 smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk);
1005 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
1006 return SMP_UNSPECIFIED;
1008 hci_le_start_enc(hcon, ediv, rand, stk, smp->enc_key_size);
1009 hcon->enc_key_size = smp->enc_key_size;
1010 set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
1011 } else {
1012 u8 stk[16], auth;
1013 __le64 rand = 0;
1014 __le16 ediv = 0;
1016 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1017 smp->prnd);
1019 smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk);
1021 if (hcon->pending_sec_level == BT_SECURITY_HIGH)
1022 auth = 1;
1023 else
1024 auth = 0;
1026 /* Even though there's no _SLAVE suffix this is the
1027 * slave STK we're adding for later lookup (the master
1028 * STK never needs to be stored).
1030 hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1031 SMP_STK, auth, stk, smp->enc_key_size, ediv, rand);
1034 return 0;
1037 static void smp_notify_keys(struct l2cap_conn *conn)
1039 struct l2cap_chan *chan = conn->smp;
1040 struct smp_chan *smp = chan->data;
1041 struct hci_conn *hcon = conn->hcon;
1042 struct hci_dev *hdev = hcon->hdev;
1043 struct smp_cmd_pairing *req = (void *) &smp->preq[1];
1044 struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1];
1045 bool persistent;
1047 if (hcon->type == ACL_LINK) {
1048 if (hcon->key_type == HCI_LK_DEBUG_COMBINATION)
1049 persistent = false;
1050 else
1051 persistent = !test_bit(HCI_CONN_FLUSH_KEY,
1052 &hcon->flags);
1053 } else {
1054 /* The LTKs, IRKs and CSRKs should be persistent only if
1055 * both sides had the bonding bit set in their
1056 * authentication requests.
1058 persistent = !!((req->auth_req & rsp->auth_req) &
1059 SMP_AUTH_BONDING);
1062 if (smp->remote_irk) {
1063 mgmt_new_irk(hdev, smp->remote_irk, persistent);
1065 /* Now that user space can be considered to know the
1066 * identity address track the connection based on it
1067 * from now on (assuming this is an LE link).
1069 if (hcon->type == LE_LINK) {
1070 bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
1071 hcon->dst_type = smp->remote_irk->addr_type;
1072 queue_work(hdev->workqueue, &conn->id_addr_update_work);
1076 if (smp->csrk) {
1077 smp->csrk->bdaddr_type = hcon->dst_type;
1078 bacpy(&smp->csrk->bdaddr, &hcon->dst);
1079 mgmt_new_csrk(hdev, smp->csrk, persistent);
1082 if (smp->slave_csrk) {
1083 smp->slave_csrk->bdaddr_type = hcon->dst_type;
1084 bacpy(&smp->slave_csrk->bdaddr, &hcon->dst);
1085 mgmt_new_csrk(hdev, smp->slave_csrk, persistent);
1088 if (smp->ltk) {
1089 smp->ltk->bdaddr_type = hcon->dst_type;
1090 bacpy(&smp->ltk->bdaddr, &hcon->dst);
1091 mgmt_new_ltk(hdev, smp->ltk, persistent);
1094 if (smp->slave_ltk) {
1095 smp->slave_ltk->bdaddr_type = hcon->dst_type;
1096 bacpy(&smp->slave_ltk->bdaddr, &hcon->dst);
1097 mgmt_new_ltk(hdev, smp->slave_ltk, persistent);
1100 if (smp->link_key) {
1101 struct link_key *key;
1102 u8 type;
1104 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1105 type = HCI_LK_DEBUG_COMBINATION;
1106 else if (hcon->sec_level == BT_SECURITY_FIPS)
1107 type = HCI_LK_AUTH_COMBINATION_P256;
1108 else
1109 type = HCI_LK_UNAUTH_COMBINATION_P256;
1111 key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst,
1112 smp->link_key, type, 0, &persistent);
1113 if (key) {
1114 mgmt_new_link_key(hdev, key, persistent);
1116 /* Don't keep debug keys around if the relevant
1117 * flag is not set.
1119 if (!hci_dev_test_flag(hdev, HCI_KEEP_DEBUG_KEYS) &&
1120 key->type == HCI_LK_DEBUG_COMBINATION) {
1121 list_del_rcu(&key->list);
1122 kfree_rcu(key, rcu);
1128 static void sc_add_ltk(struct smp_chan *smp)
1130 struct hci_conn *hcon = smp->conn->hcon;
1131 u8 key_type, auth;
1133 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1134 key_type = SMP_LTK_P256_DEBUG;
1135 else
1136 key_type = SMP_LTK_P256;
1138 if (hcon->pending_sec_level == BT_SECURITY_FIPS)
1139 auth = 1;
1140 else
1141 auth = 0;
1143 smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1144 key_type, auth, smp->tk, smp->enc_key_size,
1145 0, 0);
1148 static void sc_generate_link_key(struct smp_chan *smp)
1150 /* From core spec. Spells out in ASCII as 'lebr'. */
1151 const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c };
1153 smp->link_key = kzalloc(16, GFP_KERNEL);
1154 if (!smp->link_key)
1155 return;
1157 if (test_bit(SMP_FLAG_CT2, &smp->flags)) {
1158 /* SALT = 0x00000000000000000000000000000000746D7031 */
1159 const u8 salt[16] = { 0x31, 0x70, 0x6d, 0x74 };
1161 if (smp_h7(smp->tfm_cmac, smp->tk, salt, smp->link_key)) {
1162 kzfree(smp->link_key);
1163 smp->link_key = NULL;
1164 return;
1166 } else {
1167 /* From core spec. Spells out in ASCII as 'tmp1'. */
1168 const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 };
1170 if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) {
1171 kzfree(smp->link_key);
1172 smp->link_key = NULL;
1173 return;
1177 if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) {
1178 kzfree(smp->link_key);
1179 smp->link_key = NULL;
1180 return;
1184 static void smp_allow_key_dist(struct smp_chan *smp)
1186 /* Allow the first expected phase 3 PDU. The rest of the PDUs
1187 * will be allowed in each PDU handler to ensure we receive
1188 * them in the correct order.
1190 if (smp->remote_key_dist & SMP_DIST_ENC_KEY)
1191 SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO);
1192 else if (smp->remote_key_dist & SMP_DIST_ID_KEY)
1193 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
1194 else if (smp->remote_key_dist & SMP_DIST_SIGN)
1195 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
1198 static void sc_generate_ltk(struct smp_chan *smp)
1200 /* From core spec. Spells out in ASCII as 'brle'. */
1201 const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 };
1202 struct hci_conn *hcon = smp->conn->hcon;
1203 struct hci_dev *hdev = hcon->hdev;
1204 struct link_key *key;
1206 key = hci_find_link_key(hdev, &hcon->dst);
1207 if (!key) {
1208 BT_ERR("%s No Link Key found to generate LTK", hdev->name);
1209 return;
1212 if (key->type == HCI_LK_DEBUG_COMBINATION)
1213 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1215 if (test_bit(SMP_FLAG_CT2, &smp->flags)) {
1216 /* SALT = 0x00000000000000000000000000000000746D7032 */
1217 const u8 salt[16] = { 0x32, 0x70, 0x6d, 0x74 };
1219 if (smp_h7(smp->tfm_cmac, key->val, salt, smp->tk))
1220 return;
1221 } else {
1222 /* From core spec. Spells out in ASCII as 'tmp2'. */
1223 const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 };
1225 if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk))
1226 return;
1229 if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk))
1230 return;
1232 sc_add_ltk(smp);
1235 static void smp_distribute_keys(struct smp_chan *smp)
1237 struct smp_cmd_pairing *req, *rsp;
1238 struct l2cap_conn *conn = smp->conn;
1239 struct hci_conn *hcon = conn->hcon;
1240 struct hci_dev *hdev = hcon->hdev;
1241 __u8 *keydist;
1243 BT_DBG("conn %p", conn);
1245 rsp = (void *) &smp->prsp[1];
1247 /* The responder sends its keys first */
1248 if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) {
1249 smp_allow_key_dist(smp);
1250 return;
1253 req = (void *) &smp->preq[1];
1255 if (hcon->out) {
1256 keydist = &rsp->init_key_dist;
1257 *keydist &= req->init_key_dist;
1258 } else {
1259 keydist = &rsp->resp_key_dist;
1260 *keydist &= req->resp_key_dist;
1263 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1264 if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY))
1265 sc_generate_link_key(smp);
1266 if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY))
1267 sc_generate_ltk(smp);
1269 /* Clear the keys which are generated but not distributed */
1270 *keydist &= ~SMP_SC_NO_DIST;
1273 BT_DBG("keydist 0x%x", *keydist);
1275 if (*keydist & SMP_DIST_ENC_KEY) {
1276 struct smp_cmd_encrypt_info enc;
1277 struct smp_cmd_master_ident ident;
1278 struct smp_ltk *ltk;
1279 u8 authenticated;
1280 __le16 ediv;
1281 __le64 rand;
1283 /* Make sure we generate only the significant amount of
1284 * bytes based on the encryption key size, and set the rest
1285 * of the value to zeroes.
1287 get_random_bytes(enc.ltk, smp->enc_key_size);
1288 memset(enc.ltk + smp->enc_key_size, 0,
1289 sizeof(enc.ltk) - smp->enc_key_size);
1291 get_random_bytes(&ediv, sizeof(ediv));
1292 get_random_bytes(&rand, sizeof(rand));
1294 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);
1296 authenticated = hcon->sec_level == BT_SECURITY_HIGH;
1297 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type,
1298 SMP_LTK_SLAVE, authenticated, enc.ltk,
1299 smp->enc_key_size, ediv, rand);
1300 smp->slave_ltk = ltk;
1302 ident.ediv = ediv;
1303 ident.rand = rand;
1305 smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident);
1307 *keydist &= ~SMP_DIST_ENC_KEY;
1310 if (*keydist & SMP_DIST_ID_KEY) {
1311 struct smp_cmd_ident_addr_info addrinfo;
1312 struct smp_cmd_ident_info idinfo;
1314 memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk));
1316 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);
1318 /* The hci_conn contains the local identity address
1319 * after the connection has been established.
1321 * This is true even when the connection has been
1322 * established using a resolvable random address.
1324 bacpy(&addrinfo.bdaddr, &hcon->src);
1325 addrinfo.addr_type = hcon->src_type;
1327 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo),
1328 &addrinfo);
1330 *keydist &= ~SMP_DIST_ID_KEY;
1333 if (*keydist & SMP_DIST_SIGN) {
1334 struct smp_cmd_sign_info sign;
1335 struct smp_csrk *csrk;
1337 /* Generate a new random key */
1338 get_random_bytes(sign.csrk, sizeof(sign.csrk));
1340 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
1341 if (csrk) {
1342 if (hcon->sec_level > BT_SECURITY_MEDIUM)
1343 csrk->type = MGMT_CSRK_LOCAL_AUTHENTICATED;
1344 else
1345 csrk->type = MGMT_CSRK_LOCAL_UNAUTHENTICATED;
1346 memcpy(csrk->val, sign.csrk, sizeof(csrk->val));
1348 smp->slave_csrk = csrk;
1350 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);
1352 *keydist &= ~SMP_DIST_SIGN;
1355 /* If there are still keys to be received wait for them */
1356 if (smp->remote_key_dist & KEY_DIST_MASK) {
1357 smp_allow_key_dist(smp);
1358 return;
1361 set_bit(SMP_FLAG_COMPLETE, &smp->flags);
1362 smp_notify_keys(conn);
1364 smp_chan_destroy(conn);
1367 static void smp_timeout(struct work_struct *work)
1369 struct smp_chan *smp = container_of(work, struct smp_chan,
1370 security_timer.work);
1371 struct l2cap_conn *conn = smp->conn;
1373 BT_DBG("conn %p", conn);
1375 hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM);
1378 static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
1380 struct l2cap_chan *chan = conn->smp;
1381 struct smp_chan *smp;
1383 smp = kzalloc(sizeof(*smp), GFP_ATOMIC);
1384 if (!smp)
1385 return NULL;
1387 smp->tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
1388 if (IS_ERR(smp->tfm_aes)) {
1389 BT_ERR("Unable to create AES crypto context");
1390 kzfree(smp);
1391 return NULL;
1394 smp->tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
1395 if (IS_ERR(smp->tfm_cmac)) {
1396 BT_ERR("Unable to create CMAC crypto context");
1397 crypto_free_cipher(smp->tfm_aes);
1398 kzfree(smp);
1399 return NULL;
1402 smp->conn = conn;
1403 chan->data = smp;
1405 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL);
1407 INIT_DELAYED_WORK(&smp->security_timer, smp_timeout);
1409 hci_conn_hold(conn->hcon);
1411 return smp;
1414 static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16])
1416 struct hci_conn *hcon = smp->conn->hcon;
1417 u8 *na, *nb, a[7], b[7];
1419 if (hcon->out) {
1420 na = smp->prnd;
1421 nb = smp->rrnd;
1422 } else {
1423 na = smp->rrnd;
1424 nb = smp->prnd;
1427 memcpy(a, &hcon->init_addr, 6);
1428 memcpy(b, &hcon->resp_addr, 6);
1429 a[6] = hcon->init_addr_type;
1430 b[6] = hcon->resp_addr_type;
1432 return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk);
1435 static void sc_dhkey_check(struct smp_chan *smp)
1437 struct hci_conn *hcon = smp->conn->hcon;
1438 struct smp_cmd_dhkey_check check;
1439 u8 a[7], b[7], *local_addr, *remote_addr;
1440 u8 io_cap[3], r[16];
1442 memcpy(a, &hcon->init_addr, 6);
1443 memcpy(b, &hcon->resp_addr, 6);
1444 a[6] = hcon->init_addr_type;
1445 b[6] = hcon->resp_addr_type;
1447 if (hcon->out) {
1448 local_addr = a;
1449 remote_addr = b;
1450 memcpy(io_cap, &smp->preq[1], 3);
1451 } else {
1452 local_addr = b;
1453 remote_addr = a;
1454 memcpy(io_cap, &smp->prsp[1], 3);
1457 memset(r, 0, sizeof(r));
1459 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
1460 put_unaligned_le32(hcon->passkey_notify, r);
1462 if (smp->method == REQ_OOB)
1463 memcpy(r, smp->rr, 16);
1465 smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap,
1466 local_addr, remote_addr, check.e);
1468 smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check);
1471 static u8 sc_passkey_send_confirm(struct smp_chan *smp)
1473 struct l2cap_conn *conn = smp->conn;
1474 struct hci_conn *hcon = conn->hcon;
1475 struct smp_cmd_pairing_confirm cfm;
1476 u8 r;
1478 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1479 r |= 0x80;
1481 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1483 if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r,
1484 cfm.confirm_val))
1485 return SMP_UNSPECIFIED;
1487 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
1489 return 0;
1492 static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op)
1494 struct l2cap_conn *conn = smp->conn;
1495 struct hci_conn *hcon = conn->hcon;
1496 struct hci_dev *hdev = hcon->hdev;
1497 u8 cfm[16], r;
1499 /* Ignore the PDU if we've already done 20 rounds (0 - 19) */
1500 if (smp->passkey_round >= 20)
1501 return 0;
1503 switch (smp_op) {
1504 case SMP_CMD_PAIRING_RANDOM:
1505 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1506 r |= 0x80;
1508 if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
1509 smp->rrnd, r, cfm))
1510 return SMP_UNSPECIFIED;
1512 if (memcmp(smp->pcnf, cfm, 16))
1513 return SMP_CONFIRM_FAILED;
1515 smp->passkey_round++;
1517 if (smp->passkey_round == 20) {
1518 /* Generate MacKey and LTK */
1519 if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk))
1520 return SMP_UNSPECIFIED;
1523 /* The round is only complete when the initiator
1524 * receives pairing random.
1526 if (!hcon->out) {
1527 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1528 sizeof(smp->prnd), smp->prnd);
1529 if (smp->passkey_round == 20)
1530 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1531 else
1532 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1533 return 0;
1536 /* Start the next round */
1537 if (smp->passkey_round != 20)
1538 return sc_passkey_round(smp, 0);
1540 /* Passkey rounds are complete - start DHKey Check */
1541 sc_dhkey_check(smp);
1542 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1544 break;
1546 case SMP_CMD_PAIRING_CONFIRM:
1547 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
1548 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
1549 return 0;
1552 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1554 if (hcon->out) {
1555 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1556 sizeof(smp->prnd), smp->prnd);
1557 return 0;
1560 return sc_passkey_send_confirm(smp);
1562 case SMP_CMD_PUBLIC_KEY:
1563 default:
1564 /* Initiating device starts the round */
1565 if (!hcon->out)
1566 return 0;
1568 BT_DBG("%s Starting passkey round %u", hdev->name,
1569 smp->passkey_round + 1);
1571 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1573 return sc_passkey_send_confirm(smp);
1576 return 0;
1579 static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey)
1581 struct l2cap_conn *conn = smp->conn;
1582 struct hci_conn *hcon = conn->hcon;
1583 u8 smp_op;
1585 clear_bit(SMP_FLAG_WAIT_USER, &smp->flags);
1587 switch (mgmt_op) {
1588 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1589 smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED);
1590 return 0;
1591 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1592 smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED);
1593 return 0;
1594 case MGMT_OP_USER_PASSKEY_REPLY:
1595 hcon->passkey_notify = le32_to_cpu(passkey);
1596 smp->passkey_round = 0;
1598 if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags))
1599 smp_op = SMP_CMD_PAIRING_CONFIRM;
1600 else
1601 smp_op = 0;
1603 if (sc_passkey_round(smp, smp_op))
1604 return -EIO;
1606 return 0;
1609 /* Initiator sends DHKey check first */
1610 if (hcon->out) {
1611 sc_dhkey_check(smp);
1612 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1613 } else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) {
1614 sc_dhkey_check(smp);
1615 sc_add_ltk(smp);
1618 return 0;
1621 int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
1623 struct l2cap_conn *conn = hcon->l2cap_data;
1624 struct l2cap_chan *chan;
1625 struct smp_chan *smp;
1626 u32 value;
1627 int err;
1629 BT_DBG("");
1631 if (!conn)
1632 return -ENOTCONN;
1634 chan = conn->smp;
1635 if (!chan)
1636 return -ENOTCONN;
1638 l2cap_chan_lock(chan);
1639 if (!chan->data) {
1640 err = -ENOTCONN;
1641 goto unlock;
1644 smp = chan->data;
1646 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1647 err = sc_user_reply(smp, mgmt_op, passkey);
1648 goto unlock;
1651 switch (mgmt_op) {
1652 case MGMT_OP_USER_PASSKEY_REPLY:
1653 value = le32_to_cpu(passkey);
1654 memset(smp->tk, 0, sizeof(smp->tk));
1655 BT_DBG("PassKey: %d", value);
1656 put_unaligned_le32(value, smp->tk);
1657 /* Fall Through */
1658 case MGMT_OP_USER_CONFIRM_REPLY:
1659 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
1660 break;
1661 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1662 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1663 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1664 err = 0;
1665 goto unlock;
1666 default:
1667 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1668 err = -EOPNOTSUPP;
1669 goto unlock;
1672 err = 0;
1674 /* If it is our turn to send Pairing Confirm, do so now */
1675 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) {
1676 u8 rsp = smp_confirm(smp);
1677 if (rsp)
1678 smp_failure(conn, rsp);
1681 unlock:
1682 l2cap_chan_unlock(chan);
1683 return err;
1686 static void build_bredr_pairing_cmd(struct smp_chan *smp,
1687 struct smp_cmd_pairing *req,
1688 struct smp_cmd_pairing *rsp)
1690 struct l2cap_conn *conn = smp->conn;
1691 struct hci_dev *hdev = conn->hcon->hdev;
1692 u8 local_dist = 0, remote_dist = 0;
1694 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
1695 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1696 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1699 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
1700 remote_dist |= SMP_DIST_ID_KEY;
1702 if (hci_dev_test_flag(hdev, HCI_PRIVACY))
1703 local_dist |= SMP_DIST_ID_KEY;
1705 if (!rsp) {
1706 memset(req, 0, sizeof(*req));
1708 req->auth_req = SMP_AUTH_CT2;
1709 req->init_key_dist = local_dist;
1710 req->resp_key_dist = remote_dist;
1711 req->max_key_size = conn->hcon->enc_key_size;
1713 smp->remote_key_dist = remote_dist;
1715 return;
1718 memset(rsp, 0, sizeof(*rsp));
1720 rsp->auth_req = SMP_AUTH_CT2;
1721 rsp->max_key_size = conn->hcon->enc_key_size;
1722 rsp->init_key_dist = req->init_key_dist & remote_dist;
1723 rsp->resp_key_dist = req->resp_key_dist & local_dist;
1725 smp->remote_key_dist = rsp->init_key_dist;
1728 static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
1730 struct smp_cmd_pairing rsp, *req = (void *) skb->data;
1731 struct l2cap_chan *chan = conn->smp;
1732 struct hci_dev *hdev = conn->hcon->hdev;
1733 struct smp_chan *smp;
1734 u8 key_size, auth, sec_level;
1735 int ret;
1737 BT_DBG("conn %p", conn);
1739 if (skb->len < sizeof(*req))
1740 return SMP_INVALID_PARAMS;
1742 if (conn->hcon->role != HCI_ROLE_SLAVE)
1743 return SMP_CMD_NOTSUPP;
1745 if (!chan->data)
1746 smp = smp_chan_create(conn);
1747 else
1748 smp = chan->data;
1750 if (!smp)
1751 return SMP_UNSPECIFIED;
1753 /* We didn't start the pairing, so match remote */
1754 auth = req->auth_req & AUTH_REQ_MASK(hdev);
1756 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
1757 (auth & SMP_AUTH_BONDING))
1758 return SMP_PAIRING_NOTSUPP;
1760 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1761 return SMP_AUTH_REQUIREMENTS;
1763 smp->preq[0] = SMP_CMD_PAIRING_REQ;
1764 memcpy(&smp->preq[1], req, sizeof(*req));
1765 skb_pull(skb, sizeof(*req));
1767 /* If the remote side's OOB flag is set it means it has
1768 * successfully received our local OOB data - therefore set the
1769 * flag to indicate that local OOB is in use.
1771 if (req->oob_flag == SMP_OOB_PRESENT)
1772 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1774 /* SMP over BR/EDR requires special treatment */
1775 if (conn->hcon->type == ACL_LINK) {
1776 /* We must have a BR/EDR SC link */
1777 if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) &&
1778 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
1779 return SMP_CROSS_TRANSP_NOT_ALLOWED;
1781 set_bit(SMP_FLAG_SC, &smp->flags);
1783 build_bredr_pairing_cmd(smp, req, &rsp);
1785 if (req->auth_req & SMP_AUTH_CT2)
1786 set_bit(SMP_FLAG_CT2, &smp->flags);
1788 key_size = min(req->max_key_size, rsp.max_key_size);
1789 if (check_enc_key_size(conn, key_size))
1790 return SMP_ENC_KEY_SIZE;
1792 /* Clear bits which are generated but not distributed */
1793 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1795 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1796 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1797 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1799 smp_distribute_keys(smp);
1800 return 0;
1803 build_pairing_cmd(conn, req, &rsp, auth);
1805 if (rsp.auth_req & SMP_AUTH_SC) {
1806 set_bit(SMP_FLAG_SC, &smp->flags);
1808 if (rsp.auth_req & SMP_AUTH_CT2)
1809 set_bit(SMP_FLAG_CT2, &smp->flags);
1812 if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
1813 sec_level = BT_SECURITY_MEDIUM;
1814 else
1815 sec_level = authreq_to_seclevel(auth);
1817 if (sec_level > conn->hcon->pending_sec_level)
1818 conn->hcon->pending_sec_level = sec_level;
1820 /* If we need MITM check that it can be achieved */
1821 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1822 u8 method;
1824 method = get_auth_method(smp, conn->hcon->io_capability,
1825 req->io_capability);
1826 if (method == JUST_WORKS || method == JUST_CFM)
1827 return SMP_AUTH_REQUIREMENTS;
1830 key_size = min(req->max_key_size, rsp.max_key_size);
1831 if (check_enc_key_size(conn, key_size))
1832 return SMP_ENC_KEY_SIZE;
1834 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1836 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1837 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1839 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1841 clear_bit(SMP_FLAG_INITIATOR, &smp->flags);
1843 /* Strictly speaking we shouldn't allow Pairing Confirm for the
1844 * SC case, however some implementations incorrectly copy RFU auth
1845 * req bits from our security request, which may create a false
1846 * positive SC enablement.
1848 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1850 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1851 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
1852 /* Clear bits which are generated but not distributed */
1853 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1854 /* Wait for Public Key from Initiating Device */
1855 return 0;
1858 /* Request setup of TK */
1859 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability);
1860 if (ret)
1861 return SMP_UNSPECIFIED;
1863 return 0;
1866 static u8 sc_send_public_key(struct smp_chan *smp)
1868 struct hci_dev *hdev = smp->conn->hcon->hdev;
1870 BT_DBG("");
1872 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) {
1873 struct l2cap_chan *chan = hdev->smp_data;
1874 struct smp_dev *smp_dev;
1876 if (!chan || !chan->data)
1877 return SMP_UNSPECIFIED;
1879 smp_dev = chan->data;
1881 memcpy(smp->local_pk, smp_dev->local_pk, 64);
1882 memcpy(smp->local_sk, smp_dev->local_sk, 32);
1883 memcpy(smp->lr, smp_dev->local_rand, 16);
1885 if (smp_dev->debug_key)
1886 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1888 goto done;
1891 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
1892 BT_DBG("Using debug keys");
1893 memcpy(smp->local_pk, debug_pk, 64);
1894 memcpy(smp->local_sk, debug_sk, 32);
1895 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1896 } else {
1897 while (true) {
1898 /* Generate local key pair for Secure Connections */
1899 if (!ecc_make_key(smp->local_pk, smp->local_sk))
1900 return SMP_UNSPECIFIED;
1902 /* This is unlikely, but we need to check that
1903 * we didn't accidentially generate a debug key.
1905 if (memcmp(smp->local_sk, debug_sk, 32))
1906 break;
1910 done:
1911 SMP_DBG("Local Public Key X: %32phN", smp->local_pk);
1912 SMP_DBG("Local Public Key Y: %32phN", smp->local_pk + 32);
1913 SMP_DBG("Local Private Key: %32phN", smp->local_sk);
1915 smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk);
1917 return 0;
1920 static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
1922 struct smp_cmd_pairing *req, *rsp = (void *) skb->data;
1923 struct l2cap_chan *chan = conn->smp;
1924 struct smp_chan *smp = chan->data;
1925 struct hci_dev *hdev = conn->hcon->hdev;
1926 u8 key_size, auth;
1927 int ret;
1929 BT_DBG("conn %p", conn);
1931 if (skb->len < sizeof(*rsp))
1932 return SMP_INVALID_PARAMS;
1934 if (conn->hcon->role != HCI_ROLE_MASTER)
1935 return SMP_CMD_NOTSUPP;
1937 skb_pull(skb, sizeof(*rsp));
1939 req = (void *) &smp->preq[1];
1941 key_size = min(req->max_key_size, rsp->max_key_size);
1942 if (check_enc_key_size(conn, key_size))
1943 return SMP_ENC_KEY_SIZE;
1945 auth = rsp->auth_req & AUTH_REQ_MASK(hdev);
1947 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1948 return SMP_AUTH_REQUIREMENTS;
1950 /* If the remote side's OOB flag is set it means it has
1951 * successfully received our local OOB data - therefore set the
1952 * flag to indicate that local OOB is in use.
1954 if (rsp->oob_flag == SMP_OOB_PRESENT)
1955 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1957 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1958 memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
1960 /* Update remote key distribution in case the remote cleared
1961 * some bits that we had enabled in our request.
1963 smp->remote_key_dist &= rsp->resp_key_dist;
1965 if ((req->auth_req & SMP_AUTH_CT2) && (auth & SMP_AUTH_CT2))
1966 set_bit(SMP_FLAG_CT2, &smp->flags);
1968 /* For BR/EDR this means we're done and can start phase 3 */
1969 if (conn->hcon->type == ACL_LINK) {
1970 /* Clear bits which are generated but not distributed */
1971 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1972 smp_distribute_keys(smp);
1973 return 0;
1976 if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC))
1977 set_bit(SMP_FLAG_SC, &smp->flags);
1978 else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH)
1979 conn->hcon->pending_sec_level = BT_SECURITY_HIGH;
1981 /* If we need MITM check that it can be achieved */
1982 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1983 u8 method;
1985 method = get_auth_method(smp, req->io_capability,
1986 rsp->io_capability);
1987 if (method == JUST_WORKS || method == JUST_CFM)
1988 return SMP_AUTH_REQUIREMENTS;
1991 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1993 /* Update remote key distribution in case the remote cleared
1994 * some bits that we had enabled in our request.
1996 smp->remote_key_dist &= rsp->resp_key_dist;
1998 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1999 /* Clear bits which are generated but not distributed */
2000 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
2001 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
2002 return sc_send_public_key(smp);
2005 auth |= req->auth_req;
2007 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability);
2008 if (ret)
2009 return SMP_UNSPECIFIED;
2011 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
2013 /* Can't compose response until we have been confirmed */
2014 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
2015 return smp_confirm(smp);
2017 return 0;
2020 static u8 sc_check_confirm(struct smp_chan *smp)
2022 struct l2cap_conn *conn = smp->conn;
2024 BT_DBG("");
2026 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2027 return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM);
2029 if (conn->hcon->out) {
2030 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2031 smp->prnd);
2032 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2035 return 0;
2038 /* Work-around for some implementations that incorrectly copy RFU bits
2039 * from our security request and thereby create the impression that
2040 * we're doing SC when in fact the remote doesn't support it.
2042 static int fixup_sc_false_positive(struct smp_chan *smp)
2044 struct l2cap_conn *conn = smp->conn;
2045 struct hci_conn *hcon = conn->hcon;
2046 struct hci_dev *hdev = hcon->hdev;
2047 struct smp_cmd_pairing *req, *rsp;
2048 u8 auth;
2050 /* The issue is only observed when we're in slave role */
2051 if (hcon->out)
2052 return SMP_UNSPECIFIED;
2054 if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) {
2055 BT_ERR("Refusing SMP SC -> legacy fallback in SC-only mode");
2056 return SMP_UNSPECIFIED;
2059 BT_ERR("Trying to fall back to legacy SMP");
2061 req = (void *) &smp->preq[1];
2062 rsp = (void *) &smp->prsp[1];
2064 /* Rebuild key dist flags which may have been cleared for SC */
2065 smp->remote_key_dist = (req->init_key_dist & rsp->resp_key_dist);
2067 auth = req->auth_req & AUTH_REQ_MASK(hdev);
2069 if (tk_request(conn, 0, auth, rsp->io_capability, req->io_capability)) {
2070 BT_ERR("Failed to fall back to legacy SMP");
2071 return SMP_UNSPECIFIED;
2074 clear_bit(SMP_FLAG_SC, &smp->flags);
2076 return 0;
2079 static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
2081 struct l2cap_chan *chan = conn->smp;
2082 struct smp_chan *smp = chan->data;
2084 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
2086 if (skb->len < sizeof(smp->pcnf))
2087 return SMP_INVALID_PARAMS;
2089 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
2090 skb_pull(skb, sizeof(smp->pcnf));
2092 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
2093 int ret;
2095 /* Public Key exchange must happen before any other steps */
2096 if (test_bit(SMP_FLAG_REMOTE_PK, &smp->flags))
2097 return sc_check_confirm(smp);
2099 BT_ERR("Unexpected SMP Pairing Confirm");
2101 ret = fixup_sc_false_positive(smp);
2102 if (ret)
2103 return ret;
2106 if (conn->hcon->out) {
2107 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2108 smp->prnd);
2109 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2110 return 0;
2113 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
2114 return smp_confirm(smp);
2116 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
2118 return 0;
2121 static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
2123 struct l2cap_chan *chan = conn->smp;
2124 struct smp_chan *smp = chan->data;
2125 struct hci_conn *hcon = conn->hcon;
2126 u8 *pkax, *pkbx, *na, *nb;
2127 u32 passkey;
2128 int err;
2130 BT_DBG("conn %p", conn);
2132 if (skb->len < sizeof(smp->rrnd))
2133 return SMP_INVALID_PARAMS;
2135 memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd));
2136 skb_pull(skb, sizeof(smp->rrnd));
2138 if (!test_bit(SMP_FLAG_SC, &smp->flags))
2139 return smp_random(smp);
2141 if (hcon->out) {
2142 pkax = smp->local_pk;
2143 pkbx = smp->remote_pk;
2144 na = smp->prnd;
2145 nb = smp->rrnd;
2146 } else {
2147 pkax = smp->remote_pk;
2148 pkbx = smp->local_pk;
2149 na = smp->rrnd;
2150 nb = smp->prnd;
2153 if (smp->method == REQ_OOB) {
2154 if (!hcon->out)
2155 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2156 sizeof(smp->prnd), smp->prnd);
2157 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2158 goto mackey_and_ltk;
2161 /* Passkey entry has special treatment */
2162 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2163 return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM);
2165 if (hcon->out) {
2166 u8 cfm[16];
2168 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
2169 smp->rrnd, 0, cfm);
2170 if (err)
2171 return SMP_UNSPECIFIED;
2173 if (memcmp(smp->pcnf, cfm, 16))
2174 return SMP_CONFIRM_FAILED;
2175 } else {
2176 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2177 smp->prnd);
2178 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2181 mackey_and_ltk:
2182 /* Generate MacKey and LTK */
2183 err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk);
2184 if (err)
2185 return SMP_UNSPECIFIED;
2187 if (smp->method == JUST_WORKS || smp->method == REQ_OOB) {
2188 if (hcon->out) {
2189 sc_dhkey_check(smp);
2190 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2192 return 0;
2195 err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);
2196 if (err)
2197 return SMP_UNSPECIFIED;
2199 err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type,
2200 hcon->dst_type, passkey, 0);
2201 if (err)
2202 return SMP_UNSPECIFIED;
2204 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2206 return 0;
2209 static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
2211 struct smp_ltk *key;
2212 struct hci_conn *hcon = conn->hcon;
2214 key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role);
2215 if (!key)
2216 return false;
2218 if (smp_ltk_sec_level(key) < sec_level)
2219 return false;
2221 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
2222 return true;
2224 hci_le_start_enc(hcon, key->ediv, key->rand, key->val, key->enc_size);
2225 hcon->enc_key_size = key->enc_size;
2227 /* We never store STKs for master role, so clear this flag */
2228 clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
2230 return true;
2233 bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level,
2234 enum smp_key_pref key_pref)
2236 if (sec_level == BT_SECURITY_LOW)
2237 return true;
2239 /* If we're encrypted with an STK but the caller prefers using
2240 * LTK claim insufficient security. This way we allow the
2241 * connection to be re-encrypted with an LTK, even if the LTK
2242 * provides the same level of security. Only exception is if we
2243 * don't have an LTK (e.g. because of key distribution bits).
2245 if (key_pref == SMP_USE_LTK &&
2246 test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) &&
2247 hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role))
2248 return false;
2250 if (hcon->sec_level >= sec_level)
2251 return true;
2253 return false;
2256 static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
2258 struct smp_cmd_security_req *rp = (void *) skb->data;
2259 struct smp_cmd_pairing cp;
2260 struct hci_conn *hcon = conn->hcon;
2261 struct hci_dev *hdev = hcon->hdev;
2262 struct smp_chan *smp;
2263 u8 sec_level, auth;
2265 BT_DBG("conn %p", conn);
2267 if (skb->len < sizeof(*rp))
2268 return SMP_INVALID_PARAMS;
2270 if (hcon->role != HCI_ROLE_MASTER)
2271 return SMP_CMD_NOTSUPP;
2273 auth = rp->auth_req & AUTH_REQ_MASK(hdev);
2275 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
2276 return SMP_AUTH_REQUIREMENTS;
2278 if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
2279 sec_level = BT_SECURITY_MEDIUM;
2280 else
2281 sec_level = authreq_to_seclevel(auth);
2283 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
2284 return 0;
2286 if (sec_level > hcon->pending_sec_level)
2287 hcon->pending_sec_level = sec_level;
2289 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2290 return 0;
2292 smp = smp_chan_create(conn);
2293 if (!smp)
2294 return SMP_UNSPECIFIED;
2296 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
2297 (auth & SMP_AUTH_BONDING))
2298 return SMP_PAIRING_NOTSUPP;
2300 skb_pull(skb, sizeof(*rp));
2302 memset(&cp, 0, sizeof(cp));
2303 build_pairing_cmd(conn, &cp, NULL, auth);
2305 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2306 memcpy(&smp->preq[1], &cp, sizeof(cp));
2308 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2309 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2311 return 0;
2314 int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
2316 struct l2cap_conn *conn = hcon->l2cap_data;
2317 struct l2cap_chan *chan;
2318 struct smp_chan *smp;
2319 __u8 authreq;
2320 int ret;
2322 BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);
2324 /* This may be NULL if there's an unexpected disconnection */
2325 if (!conn)
2326 return 1;
2328 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED))
2329 return 1;
2331 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
2332 return 1;
2334 if (sec_level > hcon->pending_sec_level)
2335 hcon->pending_sec_level = sec_level;
2337 if (hcon->role == HCI_ROLE_MASTER)
2338 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2339 return 0;
2341 chan = conn->smp;
2342 if (!chan) {
2343 BT_ERR("SMP security requested but not available");
2344 return 1;
2347 l2cap_chan_lock(chan);
2349 /* If SMP is already in progress ignore this request */
2350 if (chan->data) {
2351 ret = 0;
2352 goto unlock;
2355 smp = smp_chan_create(conn);
2356 if (!smp) {
2357 ret = 1;
2358 goto unlock;
2361 authreq = seclevel_to_authreq(sec_level);
2363 if (hci_dev_test_flag(hcon->hdev, HCI_SC_ENABLED)) {
2364 authreq |= SMP_AUTH_SC;
2365 if (hci_dev_test_flag(hcon->hdev, HCI_SSP_ENABLED))
2366 authreq |= SMP_AUTH_CT2;
2369 /* Require MITM if IO Capability allows or the security level
2370 * requires it.
2372 if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT ||
2373 hcon->pending_sec_level > BT_SECURITY_MEDIUM)
2374 authreq |= SMP_AUTH_MITM;
2376 if (hcon->role == HCI_ROLE_MASTER) {
2377 struct smp_cmd_pairing cp;
2379 build_pairing_cmd(conn, &cp, NULL, authreq);
2380 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2381 memcpy(&smp->preq[1], &cp, sizeof(cp));
2383 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2384 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2385 } else {
2386 struct smp_cmd_security_req cp;
2387 cp.auth_req = authreq;
2388 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
2389 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ);
2392 set_bit(SMP_FLAG_INITIATOR, &smp->flags);
2393 ret = 0;
2395 unlock:
2396 l2cap_chan_unlock(chan);
2397 return ret;
2400 void smp_cancel_pairing(struct hci_conn *hcon)
2402 struct l2cap_conn *conn = hcon->l2cap_data;
2403 struct l2cap_chan *chan;
2404 struct smp_chan *smp;
2406 if (!conn)
2407 return;
2409 chan = conn->smp;
2410 if (!chan)
2411 return;
2413 l2cap_chan_lock(chan);
2415 smp = chan->data;
2416 if (smp) {
2417 if (test_bit(SMP_FLAG_COMPLETE, &smp->flags))
2418 smp_failure(conn, 0);
2419 else
2420 smp_failure(conn, SMP_UNSPECIFIED);
2423 l2cap_chan_unlock(chan);
2426 static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb)
2428 struct smp_cmd_encrypt_info *rp = (void *) skb->data;
2429 struct l2cap_chan *chan = conn->smp;
2430 struct smp_chan *smp = chan->data;
2432 BT_DBG("conn %p", conn);
2434 if (skb->len < sizeof(*rp))
2435 return SMP_INVALID_PARAMS;
2437 SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT);
2439 skb_pull(skb, sizeof(*rp));
2441 memcpy(smp->tk, rp->ltk, sizeof(smp->tk));
2443 return 0;
2446 static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
2448 struct smp_cmd_master_ident *rp = (void *) skb->data;
2449 struct l2cap_chan *chan = conn->smp;
2450 struct smp_chan *smp = chan->data;
2451 struct hci_dev *hdev = conn->hcon->hdev;
2452 struct hci_conn *hcon = conn->hcon;
2453 struct smp_ltk *ltk;
2454 u8 authenticated;
2456 BT_DBG("conn %p", conn);
2458 if (skb->len < sizeof(*rp))
2459 return SMP_INVALID_PARAMS;
2461 /* Mark the information as received */
2462 smp->remote_key_dist &= ~SMP_DIST_ENC_KEY;
2464 if (smp->remote_key_dist & SMP_DIST_ID_KEY)
2465 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
2466 else if (smp->remote_key_dist & SMP_DIST_SIGN)
2467 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2469 skb_pull(skb, sizeof(*rp));
2471 authenticated = (hcon->sec_level == BT_SECURITY_HIGH);
2472 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK,
2473 authenticated, smp->tk, smp->enc_key_size,
2474 rp->ediv, rp->rand);
2475 smp->ltk = ltk;
2476 if (!(smp->remote_key_dist & KEY_DIST_MASK))
2477 smp_distribute_keys(smp);
2479 return 0;
2482 static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb)
2484 struct smp_cmd_ident_info *info = (void *) skb->data;
2485 struct l2cap_chan *chan = conn->smp;
2486 struct smp_chan *smp = chan->data;
2488 BT_DBG("");
2490 if (skb->len < sizeof(*info))
2491 return SMP_INVALID_PARAMS;
2493 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO);
2495 skb_pull(skb, sizeof(*info));
2497 memcpy(smp->irk, info->irk, 16);
2499 return 0;
2502 static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,
2503 struct sk_buff *skb)
2505 struct smp_cmd_ident_addr_info *info = (void *) skb->data;
2506 struct l2cap_chan *chan = conn->smp;
2507 struct smp_chan *smp = chan->data;
2508 struct hci_conn *hcon = conn->hcon;
2509 bdaddr_t rpa;
2511 BT_DBG("");
2513 if (skb->len < sizeof(*info))
2514 return SMP_INVALID_PARAMS;
2516 /* Mark the information as received */
2517 smp->remote_key_dist &= ~SMP_DIST_ID_KEY;
2519 if (smp->remote_key_dist & SMP_DIST_SIGN)
2520 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2522 skb_pull(skb, sizeof(*info));
2524 /* Strictly speaking the Core Specification (4.1) allows sending
2525 * an empty address which would force us to rely on just the IRK
2526 * as "identity information". However, since such
2527 * implementations are not known of and in order to not over
2528 * complicate our implementation, simply pretend that we never
2529 * received an IRK for such a device.
2531 * The Identity Address must also be a Static Random or Public
2532 * Address, which hci_is_identity_address() checks for.
2534 if (!bacmp(&info->bdaddr, BDADDR_ANY) ||
2535 !hci_is_identity_address(&info->bdaddr, info->addr_type)) {
2536 BT_ERR("Ignoring IRK with no identity address");
2537 goto distribute;
2540 bacpy(&smp->id_addr, &info->bdaddr);
2541 smp->id_addr_type = info->addr_type;
2543 if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type))
2544 bacpy(&rpa, &hcon->dst);
2545 else
2546 bacpy(&rpa, BDADDR_ANY);
2548 smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr,
2549 smp->id_addr_type, smp->irk, &rpa);
2551 distribute:
2552 if (!(smp->remote_key_dist & KEY_DIST_MASK))
2553 smp_distribute_keys(smp);
2555 return 0;
2558 static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb)
2560 struct smp_cmd_sign_info *rp = (void *) skb->data;
2561 struct l2cap_chan *chan = conn->smp;
2562 struct smp_chan *smp = chan->data;
2563 struct smp_csrk *csrk;
2565 BT_DBG("conn %p", conn);
2567 if (skb->len < sizeof(*rp))
2568 return SMP_INVALID_PARAMS;
2570 /* Mark the information as received */
2571 smp->remote_key_dist &= ~SMP_DIST_SIGN;
2573 skb_pull(skb, sizeof(*rp));
2575 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
2576 if (csrk) {
2577 if (conn->hcon->sec_level > BT_SECURITY_MEDIUM)
2578 csrk->type = MGMT_CSRK_REMOTE_AUTHENTICATED;
2579 else
2580 csrk->type = MGMT_CSRK_REMOTE_UNAUTHENTICATED;
2581 memcpy(csrk->val, rp->csrk, sizeof(csrk->val));
2583 smp->csrk = csrk;
2584 smp_distribute_keys(smp);
2586 return 0;
2589 static u8 sc_select_method(struct smp_chan *smp)
2591 struct l2cap_conn *conn = smp->conn;
2592 struct hci_conn *hcon = conn->hcon;
2593 struct smp_cmd_pairing *local, *remote;
2594 u8 local_mitm, remote_mitm, local_io, remote_io, method;
2596 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags) ||
2597 test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags))
2598 return REQ_OOB;
2600 /* The preq/prsp contain the raw Pairing Request/Response PDUs
2601 * which are needed as inputs to some crypto functions. To get
2602 * the "struct smp_cmd_pairing" from them we need to skip the
2603 * first byte which contains the opcode.
2605 if (hcon->out) {
2606 local = (void *) &smp->preq[1];
2607 remote = (void *) &smp->prsp[1];
2608 } else {
2609 local = (void *) &smp->prsp[1];
2610 remote = (void *) &smp->preq[1];
2613 local_io = local->io_capability;
2614 remote_io = remote->io_capability;
2616 local_mitm = (local->auth_req & SMP_AUTH_MITM);
2617 remote_mitm = (remote->auth_req & SMP_AUTH_MITM);
2619 /* If either side wants MITM, look up the method from the table,
2620 * otherwise use JUST WORKS.
2622 if (local_mitm || remote_mitm)
2623 method = get_auth_method(smp, local_io, remote_io);
2624 else
2625 method = JUST_WORKS;
2627 /* Don't confirm locally initiated pairing attempts */
2628 if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags))
2629 method = JUST_WORKS;
2631 return method;
2634 static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb)
2636 struct smp_cmd_public_key *key = (void *) skb->data;
2637 struct hci_conn *hcon = conn->hcon;
2638 struct l2cap_chan *chan = conn->smp;
2639 struct smp_chan *smp = chan->data;
2640 struct hci_dev *hdev = hcon->hdev;
2641 struct smp_cmd_pairing_confirm cfm;
2642 int err;
2644 BT_DBG("conn %p", conn);
2646 if (skb->len < sizeof(*key))
2647 return SMP_INVALID_PARAMS;
2649 memcpy(smp->remote_pk, key, 64);
2651 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags)) {
2652 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk,
2653 smp->rr, 0, cfm.confirm_val);
2654 if (err)
2655 return SMP_UNSPECIFIED;
2657 if (memcmp(cfm.confirm_val, smp->pcnf, 16))
2658 return SMP_CONFIRM_FAILED;
2661 /* Non-initiating device sends its public key after receiving
2662 * the key from the initiating device.
2664 if (!hcon->out) {
2665 err = sc_send_public_key(smp);
2666 if (err)
2667 return err;
2670 SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk);
2671 SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32);
2673 if (!ecdh_shared_secret(smp->remote_pk, smp->local_sk, smp->dhkey))
2674 return SMP_UNSPECIFIED;
2676 SMP_DBG("DHKey %32phN", smp->dhkey);
2678 set_bit(SMP_FLAG_REMOTE_PK, &smp->flags);
2680 smp->method = sc_select_method(smp);
2682 BT_DBG("%s selected method 0x%02x", hdev->name, smp->method);
2684 /* JUST_WORKS and JUST_CFM result in an unauthenticated key */
2685 if (smp->method == JUST_WORKS || smp->method == JUST_CFM)
2686 hcon->pending_sec_level = BT_SECURITY_MEDIUM;
2687 else
2688 hcon->pending_sec_level = BT_SECURITY_FIPS;
2690 if (!memcmp(debug_pk, smp->remote_pk, 64))
2691 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
2693 if (smp->method == DSP_PASSKEY) {
2694 get_random_bytes(&hcon->passkey_notify,
2695 sizeof(hcon->passkey_notify));
2696 hcon->passkey_notify %= 1000000;
2697 hcon->passkey_entered = 0;
2698 smp->passkey_round = 0;
2699 if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type,
2700 hcon->dst_type,
2701 hcon->passkey_notify,
2702 hcon->passkey_entered))
2703 return SMP_UNSPECIFIED;
2704 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2705 return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY);
2708 if (smp->method == REQ_OOB) {
2709 if (hcon->out)
2710 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2711 sizeof(smp->prnd), smp->prnd);
2713 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2715 return 0;
2718 if (hcon->out)
2719 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2721 if (smp->method == REQ_PASSKEY) {
2722 if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type,
2723 hcon->dst_type))
2724 return SMP_UNSPECIFIED;
2725 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2726 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2727 return 0;
2730 /* The Initiating device waits for the non-initiating device to
2731 * send the confirm value.
2733 if (conn->hcon->out)
2734 return 0;
2736 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd,
2737 0, cfm.confirm_val);
2738 if (err)
2739 return SMP_UNSPECIFIED;
2741 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
2742 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2744 return 0;
2747 static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb)
2749 struct smp_cmd_dhkey_check *check = (void *) skb->data;
2750 struct l2cap_chan *chan = conn->smp;
2751 struct hci_conn *hcon = conn->hcon;
2752 struct smp_chan *smp = chan->data;
2753 u8 a[7], b[7], *local_addr, *remote_addr;
2754 u8 io_cap[3], r[16], e[16];
2755 int err;
2757 BT_DBG("conn %p", conn);
2759 if (skb->len < sizeof(*check))
2760 return SMP_INVALID_PARAMS;
2762 memcpy(a, &hcon->init_addr, 6);
2763 memcpy(b, &hcon->resp_addr, 6);
2764 a[6] = hcon->init_addr_type;
2765 b[6] = hcon->resp_addr_type;
2767 if (hcon->out) {
2768 local_addr = a;
2769 remote_addr = b;
2770 memcpy(io_cap, &smp->prsp[1], 3);
2771 } else {
2772 local_addr = b;
2773 remote_addr = a;
2774 memcpy(io_cap, &smp->preq[1], 3);
2777 memset(r, 0, sizeof(r));
2779 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2780 put_unaligned_le32(hcon->passkey_notify, r);
2781 else if (smp->method == REQ_OOB)
2782 memcpy(r, smp->lr, 16);
2784 err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r,
2785 io_cap, remote_addr, local_addr, e);
2786 if (err)
2787 return SMP_UNSPECIFIED;
2789 if (memcmp(check->e, e, 16))
2790 return SMP_DHKEY_CHECK_FAILED;
2792 if (!hcon->out) {
2793 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
2794 set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags);
2795 return 0;
2798 /* Slave sends DHKey check as response to master */
2799 sc_dhkey_check(smp);
2802 sc_add_ltk(smp);
2804 if (hcon->out) {
2805 hci_le_start_enc(hcon, 0, 0, smp->tk, smp->enc_key_size);
2806 hcon->enc_key_size = smp->enc_key_size;
2809 return 0;
2812 static int smp_cmd_keypress_notify(struct l2cap_conn *conn,
2813 struct sk_buff *skb)
2815 struct smp_cmd_keypress_notify *kp = (void *) skb->data;
2817 BT_DBG("value 0x%02x", kp->value);
2819 return 0;
2822 static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb)
2824 struct l2cap_conn *conn = chan->conn;
2825 struct hci_conn *hcon = conn->hcon;
2826 struct smp_chan *smp;
2827 __u8 code, reason;
2828 int err = 0;
2830 if (skb->len < 1)
2831 return -EILSEQ;
2833 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) {
2834 reason = SMP_PAIRING_NOTSUPP;
2835 goto done;
2838 code = skb->data[0];
2839 skb_pull(skb, sizeof(code));
2841 smp = chan->data;
2843 if (code > SMP_CMD_MAX)
2844 goto drop;
2846 if (smp && !test_and_clear_bit(code, &smp->allow_cmd))
2847 goto drop;
2849 /* If we don't have a context the only allowed commands are
2850 * pairing request and security request.
2852 if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ)
2853 goto drop;
2855 switch (code) {
2856 case SMP_CMD_PAIRING_REQ:
2857 reason = smp_cmd_pairing_req(conn, skb);
2858 break;
2860 case SMP_CMD_PAIRING_FAIL:
2861 smp_failure(conn, 0);
2862 err = -EPERM;
2863 break;
2865 case SMP_CMD_PAIRING_RSP:
2866 reason = smp_cmd_pairing_rsp(conn, skb);
2867 break;
2869 case SMP_CMD_SECURITY_REQ:
2870 reason = smp_cmd_security_req(conn, skb);
2871 break;
2873 case SMP_CMD_PAIRING_CONFIRM:
2874 reason = smp_cmd_pairing_confirm(conn, skb);
2875 break;
2877 case SMP_CMD_PAIRING_RANDOM:
2878 reason = smp_cmd_pairing_random(conn, skb);
2879 break;
2881 case SMP_CMD_ENCRYPT_INFO:
2882 reason = smp_cmd_encrypt_info(conn, skb);
2883 break;
2885 case SMP_CMD_MASTER_IDENT:
2886 reason = smp_cmd_master_ident(conn, skb);
2887 break;
2889 case SMP_CMD_IDENT_INFO:
2890 reason = smp_cmd_ident_info(conn, skb);
2891 break;
2893 case SMP_CMD_IDENT_ADDR_INFO:
2894 reason = smp_cmd_ident_addr_info(conn, skb);
2895 break;
2897 case SMP_CMD_SIGN_INFO:
2898 reason = smp_cmd_sign_info(conn, skb);
2899 break;
2901 case SMP_CMD_PUBLIC_KEY:
2902 reason = smp_cmd_public_key(conn, skb);
2903 break;
2905 case SMP_CMD_DHKEY_CHECK:
2906 reason = smp_cmd_dhkey_check(conn, skb);
2907 break;
2909 case SMP_CMD_KEYPRESS_NOTIFY:
2910 reason = smp_cmd_keypress_notify(conn, skb);
2911 break;
2913 default:
2914 BT_DBG("Unknown command code 0x%2.2x", code);
2915 reason = SMP_CMD_NOTSUPP;
2916 goto done;
2919 done:
2920 if (!err) {
2921 if (reason)
2922 smp_failure(conn, reason);
2923 kfree_skb(skb);
2926 return err;
2928 drop:
2929 BT_ERR("%s unexpected SMP command 0x%02x from %pMR", hcon->hdev->name,
2930 code, &hcon->dst);
2931 kfree_skb(skb);
2932 return 0;
2935 static void smp_teardown_cb(struct l2cap_chan *chan, int err)
2937 struct l2cap_conn *conn = chan->conn;
2939 BT_DBG("chan %p", chan);
2941 if (chan->data)
2942 smp_chan_destroy(conn);
2944 conn->smp = NULL;
2945 l2cap_chan_put(chan);
2948 static void bredr_pairing(struct l2cap_chan *chan)
2950 struct l2cap_conn *conn = chan->conn;
2951 struct hci_conn *hcon = conn->hcon;
2952 struct hci_dev *hdev = hcon->hdev;
2953 struct smp_cmd_pairing req;
2954 struct smp_chan *smp;
2956 BT_DBG("chan %p", chan);
2958 /* Only new pairings are interesting */
2959 if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags))
2960 return;
2962 /* Don't bother if we're not encrypted */
2963 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
2964 return;
2966 /* Only master may initiate SMP over BR/EDR */
2967 if (hcon->role != HCI_ROLE_MASTER)
2968 return;
2970 /* Secure Connections support must be enabled */
2971 if (!hci_dev_test_flag(hdev, HCI_SC_ENABLED))
2972 return;
2974 /* BR/EDR must use Secure Connections for SMP */
2975 if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) &&
2976 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
2977 return;
2979 /* If our LE support is not enabled don't do anything */
2980 if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED))
2981 return;
2983 /* Don't bother if remote LE support is not enabled */
2984 if (!lmp_host_le_capable(hcon))
2985 return;
2987 /* Remote must support SMP fixed chan for BR/EDR */
2988 if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR))
2989 return;
2991 /* Don't bother if SMP is already ongoing */
2992 if (chan->data)
2993 return;
2995 smp = smp_chan_create(conn);
2996 if (!smp) {
2997 BT_ERR("%s unable to create SMP context for BR/EDR",
2998 hdev->name);
2999 return;
3002 set_bit(SMP_FLAG_SC, &smp->flags);
3004 BT_DBG("%s starting SMP over BR/EDR", hdev->name);
3006 /* Prepare and send the BR/EDR SMP Pairing Request */
3007 build_bredr_pairing_cmd(smp, &req, NULL);
3009 smp->preq[0] = SMP_CMD_PAIRING_REQ;
3010 memcpy(&smp->preq[1], &req, sizeof(req));
3012 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req);
3013 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
3016 static void smp_resume_cb(struct l2cap_chan *chan)
3018 struct smp_chan *smp = chan->data;
3019 struct l2cap_conn *conn = chan->conn;
3020 struct hci_conn *hcon = conn->hcon;
3022 BT_DBG("chan %p", chan);
3024 if (hcon->type == ACL_LINK) {
3025 bredr_pairing(chan);
3026 return;
3029 if (!smp)
3030 return;
3032 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
3033 return;
3035 cancel_delayed_work(&smp->security_timer);
3037 smp_distribute_keys(smp);
3040 static void smp_ready_cb(struct l2cap_chan *chan)
3042 struct l2cap_conn *conn = chan->conn;
3043 struct hci_conn *hcon = conn->hcon;
3045 BT_DBG("chan %p", chan);
3047 /* No need to call l2cap_chan_hold() here since we already own
3048 * the reference taken in smp_new_conn_cb(). This is just the
3049 * first time that we tie it to a specific pointer. The code in
3050 * l2cap_core.c ensures that there's no risk this function wont
3051 * get called if smp_new_conn_cb was previously called.
3053 conn->smp = chan;
3055 if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
3056 bredr_pairing(chan);
3059 static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
3061 int err;
3063 BT_DBG("chan %p", chan);
3065 err = smp_sig_channel(chan, skb);
3066 if (err) {
3067 struct smp_chan *smp = chan->data;
3069 if (smp)
3070 cancel_delayed_work_sync(&smp->security_timer);
3072 hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE);
3075 return err;
3078 static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan,
3079 unsigned long hdr_len,
3080 unsigned long len, int nb)
3082 struct sk_buff *skb;
3084 skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL);
3085 if (!skb)
3086 return ERR_PTR(-ENOMEM);
3088 skb->priority = HCI_PRIO_MAX;
3089 bt_cb(skb)->l2cap.chan = chan;
3091 return skb;
3094 static const struct l2cap_ops smp_chan_ops = {
3095 .name = "Security Manager",
3096 .ready = smp_ready_cb,
3097 .recv = smp_recv_cb,
3098 .alloc_skb = smp_alloc_skb_cb,
3099 .teardown = smp_teardown_cb,
3100 .resume = smp_resume_cb,
3102 .new_connection = l2cap_chan_no_new_connection,
3103 .state_change = l2cap_chan_no_state_change,
3104 .close = l2cap_chan_no_close,
3105 .defer = l2cap_chan_no_defer,
3106 .suspend = l2cap_chan_no_suspend,
3107 .set_shutdown = l2cap_chan_no_set_shutdown,
3108 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
3111 static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan)
3113 struct l2cap_chan *chan;
3115 BT_DBG("pchan %p", pchan);
3117 chan = l2cap_chan_create();
3118 if (!chan)
3119 return NULL;
3121 chan->chan_type = pchan->chan_type;
3122 chan->ops = &smp_chan_ops;
3123 chan->scid = pchan->scid;
3124 chan->dcid = chan->scid;
3125 chan->imtu = pchan->imtu;
3126 chan->omtu = pchan->omtu;
3127 chan->mode = pchan->mode;
3129 /* Other L2CAP channels may request SMP routines in order to
3130 * change the security level. This means that the SMP channel
3131 * lock must be considered in its own category to avoid lockdep
3132 * warnings.
3134 atomic_set(&chan->nesting, L2CAP_NESTING_SMP);
3136 BT_DBG("created chan %p", chan);
3138 return chan;
3141 static const struct l2cap_ops smp_root_chan_ops = {
3142 .name = "Security Manager Root",
3143 .new_connection = smp_new_conn_cb,
3145 /* None of these are implemented for the root channel */
3146 .close = l2cap_chan_no_close,
3147 .alloc_skb = l2cap_chan_no_alloc_skb,
3148 .recv = l2cap_chan_no_recv,
3149 .state_change = l2cap_chan_no_state_change,
3150 .teardown = l2cap_chan_no_teardown,
3151 .ready = l2cap_chan_no_ready,
3152 .defer = l2cap_chan_no_defer,
3153 .suspend = l2cap_chan_no_suspend,
3154 .resume = l2cap_chan_no_resume,
3155 .set_shutdown = l2cap_chan_no_set_shutdown,
3156 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
3159 static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid)
3161 struct l2cap_chan *chan;
3162 struct smp_dev *smp;
3163 struct crypto_cipher *tfm_aes;
3164 struct crypto_shash *tfm_cmac;
3166 if (cid == L2CAP_CID_SMP_BREDR) {
3167 smp = NULL;
3168 goto create_chan;
3171 smp = kzalloc(sizeof(*smp), GFP_KERNEL);
3172 if (!smp)
3173 return ERR_PTR(-ENOMEM);
3175 tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
3176 if (IS_ERR(tfm_aes)) {
3177 BT_ERR("Unable to create AES crypto context");
3178 kzfree(smp);
3179 return ERR_CAST(tfm_aes);
3182 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
3183 if (IS_ERR(tfm_cmac)) {
3184 BT_ERR("Unable to create CMAC crypto context");
3185 crypto_free_cipher(tfm_aes);
3186 kzfree(smp);
3187 return ERR_CAST(tfm_cmac);
3190 smp->tfm_aes = tfm_aes;
3191 smp->tfm_cmac = tfm_cmac;
3192 smp->min_key_size = SMP_MIN_ENC_KEY_SIZE;
3193 smp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
3195 create_chan:
3196 chan = l2cap_chan_create();
3197 if (!chan) {
3198 if (smp) {
3199 crypto_free_cipher(smp->tfm_aes);
3200 crypto_free_shash(smp->tfm_cmac);
3201 kzfree(smp);
3203 return ERR_PTR(-ENOMEM);
3206 chan->data = smp;
3208 l2cap_add_scid(chan, cid);
3210 l2cap_chan_set_defaults(chan);
3212 if (cid == L2CAP_CID_SMP) {
3213 u8 bdaddr_type;
3215 hci_copy_identity_address(hdev, &chan->src, &bdaddr_type);
3217 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
3218 chan->src_type = BDADDR_LE_PUBLIC;
3219 else
3220 chan->src_type = BDADDR_LE_RANDOM;
3221 } else {
3222 bacpy(&chan->src, &hdev->bdaddr);
3223 chan->src_type = BDADDR_BREDR;
3226 chan->state = BT_LISTEN;
3227 chan->mode = L2CAP_MODE_BASIC;
3228 chan->imtu = L2CAP_DEFAULT_MTU;
3229 chan->ops = &smp_root_chan_ops;
3231 /* Set correct nesting level for a parent/listening channel */
3232 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
3234 return chan;
3237 static void smp_del_chan(struct l2cap_chan *chan)
3239 struct smp_dev *smp;
3241 BT_DBG("chan %p", chan);
3243 smp = chan->data;
3244 if (smp) {
3245 chan->data = NULL;
3246 crypto_free_cipher(smp->tfm_aes);
3247 crypto_free_shash(smp->tfm_cmac);
3248 kzfree(smp);
3251 l2cap_chan_put(chan);
3254 static ssize_t force_bredr_smp_read(struct file *file,
3255 char __user *user_buf,
3256 size_t count, loff_t *ppos)
3258 struct hci_dev *hdev = file->private_data;
3259 char buf[3];
3261 buf[0] = hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP) ? 'Y': 'N';
3262 buf[1] = '\n';
3263 buf[2] = '\0';
3264 return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
3267 static ssize_t force_bredr_smp_write(struct file *file,
3268 const char __user *user_buf,
3269 size_t count, loff_t *ppos)
3271 struct hci_dev *hdev = file->private_data;
3272 char buf[32];
3273 size_t buf_size = min(count, (sizeof(buf)-1));
3274 bool enable;
3276 if (copy_from_user(buf, user_buf, buf_size))
3277 return -EFAULT;
3279 buf[buf_size] = '\0';
3280 if (strtobool(buf, &enable))
3281 return -EINVAL;
3283 if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3284 return -EALREADY;
3286 if (enable) {
3287 struct l2cap_chan *chan;
3289 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3290 if (IS_ERR(chan))
3291 return PTR_ERR(chan);
3293 hdev->smp_bredr_data = chan;
3294 } else {
3295 struct l2cap_chan *chan;
3297 chan = hdev->smp_bredr_data;
3298 hdev->smp_bredr_data = NULL;
3299 smp_del_chan(chan);
3302 hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP);
3304 return count;
3307 static const struct file_operations force_bredr_smp_fops = {
3308 .open = simple_open,
3309 .read = force_bredr_smp_read,
3310 .write = force_bredr_smp_write,
3311 .llseek = default_llseek,
3314 static ssize_t le_min_key_size_read(struct file *file,
3315 char __user *user_buf,
3316 size_t count, loff_t *ppos)
3318 struct hci_dev *hdev = file->private_data;
3319 char buf[4];
3321 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->min_key_size);
3323 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf));
3326 static ssize_t le_min_key_size_write(struct file *file,
3327 const char __user *user_buf,
3328 size_t count, loff_t *ppos)
3330 struct hci_dev *hdev = file->private_data;
3331 char buf[32];
3332 size_t buf_size = min(count, (sizeof(buf) - 1));
3333 u8 key_size;
3335 if (copy_from_user(buf, user_buf, buf_size))
3336 return -EFAULT;
3338 buf[buf_size] = '\0';
3340 sscanf(buf, "%hhu", &key_size);
3342 if (key_size > SMP_DEV(hdev)->max_key_size ||
3343 key_size < SMP_MIN_ENC_KEY_SIZE)
3344 return -EINVAL;
3346 SMP_DEV(hdev)->min_key_size = key_size;
3348 return count;
3351 static const struct file_operations le_min_key_size_fops = {
3352 .open = simple_open,
3353 .read = le_min_key_size_read,
3354 .write = le_min_key_size_write,
3355 .llseek = default_llseek,
3358 static ssize_t le_max_key_size_read(struct file *file,
3359 char __user *user_buf,
3360 size_t count, loff_t *ppos)
3362 struct hci_dev *hdev = file->private_data;
3363 char buf[4];
3365 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->max_key_size);
3367 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf));
3370 static ssize_t le_max_key_size_write(struct file *file,
3371 const char __user *user_buf,
3372 size_t count, loff_t *ppos)
3374 struct hci_dev *hdev = file->private_data;
3375 char buf[32];
3376 size_t buf_size = min(count, (sizeof(buf) - 1));
3377 u8 key_size;
3379 if (copy_from_user(buf, user_buf, buf_size))
3380 return -EFAULT;
3382 buf[buf_size] = '\0';
3384 sscanf(buf, "%hhu", &key_size);
3386 if (key_size > SMP_MAX_ENC_KEY_SIZE ||
3387 key_size < SMP_DEV(hdev)->min_key_size)
3388 return -EINVAL;
3390 SMP_DEV(hdev)->max_key_size = key_size;
3392 return count;
3395 static const struct file_operations le_max_key_size_fops = {
3396 .open = simple_open,
3397 .read = le_max_key_size_read,
3398 .write = le_max_key_size_write,
3399 .llseek = default_llseek,
3402 int smp_register(struct hci_dev *hdev)
3404 struct l2cap_chan *chan;
3406 BT_DBG("%s", hdev->name);
3408 /* If the controller does not support Low Energy operation, then
3409 * there is also no need to register any SMP channel.
3411 if (!lmp_le_capable(hdev))
3412 return 0;
3414 if (WARN_ON(hdev->smp_data)) {
3415 chan = hdev->smp_data;
3416 hdev->smp_data = NULL;
3417 smp_del_chan(chan);
3420 chan = smp_add_cid(hdev, L2CAP_CID_SMP);
3421 if (IS_ERR(chan))
3422 return PTR_ERR(chan);
3424 hdev->smp_data = chan;
3426 debugfs_create_file("le_min_key_size", 0644, hdev->debugfs, hdev,
3427 &le_min_key_size_fops);
3428 debugfs_create_file("le_max_key_size", 0644, hdev->debugfs, hdev,
3429 &le_max_key_size_fops);
3431 /* If the controller does not support BR/EDR Secure Connections
3432 * feature, then the BR/EDR SMP channel shall not be present.
3434 * To test this with Bluetooth 4.0 controllers, create a debugfs
3435 * switch that allows forcing BR/EDR SMP support and accepting
3436 * cross-transport pairing on non-AES encrypted connections.
3438 if (!lmp_sc_capable(hdev)) {
3439 debugfs_create_file("force_bredr_smp", 0644, hdev->debugfs,
3440 hdev, &force_bredr_smp_fops);
3442 /* Flag can be already set here (due to power toggle) */
3443 if (!hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3444 return 0;
3447 if (WARN_ON(hdev->smp_bredr_data)) {
3448 chan = hdev->smp_bredr_data;
3449 hdev->smp_bredr_data = NULL;
3450 smp_del_chan(chan);
3453 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3454 if (IS_ERR(chan)) {
3455 int err = PTR_ERR(chan);
3456 chan = hdev->smp_data;
3457 hdev->smp_data = NULL;
3458 smp_del_chan(chan);
3459 return err;
3462 hdev->smp_bredr_data = chan;
3464 return 0;
3467 void smp_unregister(struct hci_dev *hdev)
3469 struct l2cap_chan *chan;
3471 if (hdev->smp_bredr_data) {
3472 chan = hdev->smp_bredr_data;
3473 hdev->smp_bredr_data = NULL;
3474 smp_del_chan(chan);
3477 if (hdev->smp_data) {
3478 chan = hdev->smp_data;
3479 hdev->smp_data = NULL;
3480 smp_del_chan(chan);
3484 #if IS_ENABLED(CONFIG_BT_SELFTEST_SMP)
3486 static int __init test_ah(struct crypto_cipher *tfm_aes)
3488 const u8 irk[16] = {
3489 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3490 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3491 const u8 r[3] = { 0x94, 0x81, 0x70 };
3492 const u8 exp[3] = { 0xaa, 0xfb, 0x0d };
3493 u8 res[3];
3494 int err;
3496 err = smp_ah(tfm_aes, irk, r, res);
3497 if (err)
3498 return err;
3500 if (memcmp(res, exp, 3))
3501 return -EINVAL;
3503 return 0;
3506 static int __init test_c1(struct crypto_cipher *tfm_aes)
3508 const u8 k[16] = {
3509 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
3510 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
3511 const u8 r[16] = {
3512 0xe0, 0x2e, 0x70, 0xc6, 0x4e, 0x27, 0x88, 0x63,
3513 0x0e, 0x6f, 0xad, 0x56, 0x21, 0xd5, 0x83, 0x57 };
3514 const u8 preq[7] = { 0x01, 0x01, 0x00, 0x00, 0x10, 0x07, 0x07 };
3515 const u8 pres[7] = { 0x02, 0x03, 0x00, 0x00, 0x08, 0x00, 0x05 };
3516 const u8 _iat = 0x01;
3517 const u8 _rat = 0x00;
3518 const bdaddr_t ra = { { 0xb6, 0xb5, 0xb4, 0xb3, 0xb2, 0xb1 } };
3519 const bdaddr_t ia = { { 0xa6, 0xa5, 0xa4, 0xa3, 0xa2, 0xa1 } };
3520 const u8 exp[16] = {
3521 0x86, 0x3b, 0xf1, 0xbe, 0xc5, 0x4d, 0xa7, 0xd2,
3522 0xea, 0x88, 0x89, 0x87, 0xef, 0x3f, 0x1e, 0x1e };
3523 u8 res[16];
3524 int err;
3526 err = smp_c1(tfm_aes, k, r, preq, pres, _iat, &ia, _rat, &ra, res);
3527 if (err)
3528 return err;
3530 if (memcmp(res, exp, 16))
3531 return -EINVAL;
3533 return 0;
3536 static int __init test_s1(struct crypto_cipher *tfm_aes)
3538 const u8 k[16] = {
3539 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
3540 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
3541 const u8 r1[16] = {
3542 0x88, 0x77, 0x66, 0x55, 0x44, 0x33, 0x22, 0x11 };
3543 const u8 r2[16] = {
3544 0x00, 0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa, 0x99 };
3545 const u8 exp[16] = {
3546 0x62, 0xa0, 0x6d, 0x79, 0xae, 0x16, 0x42, 0x5b,
3547 0x9b, 0xf4, 0xb0, 0xe8, 0xf0, 0xe1, 0x1f, 0x9a };
3548 u8 res[16];
3549 int err;
3551 err = smp_s1(tfm_aes, k, r1, r2, res);
3552 if (err)
3553 return err;
3555 if (memcmp(res, exp, 16))
3556 return -EINVAL;
3558 return 0;
3561 static int __init test_f4(struct crypto_shash *tfm_cmac)
3563 const u8 u[32] = {
3564 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
3565 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
3566 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
3567 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 };
3568 const u8 v[32] = {
3569 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b,
3570 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59,
3571 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90,
3572 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 };
3573 const u8 x[16] = {
3574 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3575 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3576 const u8 z = 0x00;
3577 const u8 exp[16] = {
3578 0x2d, 0x87, 0x74, 0xa9, 0xbe, 0xa1, 0xed, 0xf1,
3579 0x1c, 0xbd, 0xa9, 0x07, 0xf1, 0x16, 0xc9, 0xf2 };
3580 u8 res[16];
3581 int err;
3583 err = smp_f4(tfm_cmac, u, v, x, z, res);
3584 if (err)
3585 return err;
3587 if (memcmp(res, exp, 16))
3588 return -EINVAL;
3590 return 0;
3593 static int __init test_f5(struct crypto_shash *tfm_cmac)
3595 const u8 w[32] = {
3596 0x98, 0xa6, 0xbf, 0x73, 0xf3, 0x34, 0x8d, 0x86,
3597 0xf1, 0x66, 0xf8, 0xb4, 0x13, 0x6b, 0x79, 0x99,
3598 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3599 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3600 const u8 n1[16] = {
3601 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3602 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3603 const u8 n2[16] = {
3604 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3605 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3606 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 };
3607 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 };
3608 const u8 exp_ltk[16] = {
3609 0x38, 0x0a, 0x75, 0x94, 0xb5, 0x22, 0x05, 0x98,
3610 0x23, 0xcd, 0xd7, 0x69, 0x11, 0x79, 0x86, 0x69 };
3611 const u8 exp_mackey[16] = {
3612 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd,
3613 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 };
3614 u8 mackey[16], ltk[16];
3615 int err;
3617 err = smp_f5(tfm_cmac, w, n1, n2, a1, a2, mackey, ltk);
3618 if (err)
3619 return err;
3621 if (memcmp(mackey, exp_mackey, 16))
3622 return -EINVAL;
3624 if (memcmp(ltk, exp_ltk, 16))
3625 return -EINVAL;
3627 return 0;
3630 static int __init test_f6(struct crypto_shash *tfm_cmac)
3632 const u8 w[16] = {
3633 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd,
3634 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 };
3635 const u8 n1[16] = {
3636 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3637 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3638 const u8 n2[16] = {
3639 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3640 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3641 const u8 r[16] = {
3642 0xc8, 0x0f, 0x2d, 0x0c, 0xd2, 0x42, 0xda, 0x08,
3643 0x54, 0xbb, 0x53, 0xb4, 0x3b, 0x34, 0xa3, 0x12 };
3644 const u8 io_cap[3] = { 0x02, 0x01, 0x01 };
3645 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 };
3646 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 };
3647 const u8 exp[16] = {
3648 0x61, 0x8f, 0x95, 0xda, 0x09, 0x0b, 0x6c, 0xd2,
3649 0xc5, 0xe8, 0xd0, 0x9c, 0x98, 0x73, 0xc4, 0xe3 };
3650 u8 res[16];
3651 int err;
3653 err = smp_f6(tfm_cmac, w, n1, n2, r, io_cap, a1, a2, res);
3654 if (err)
3655 return err;
3657 if (memcmp(res, exp, 16))
3658 return -EINVAL;
3660 return 0;
3663 static int __init test_g2(struct crypto_shash *tfm_cmac)
3665 const u8 u[32] = {
3666 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
3667 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
3668 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
3669 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 };
3670 const u8 v[32] = {
3671 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b,
3672 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59,
3673 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90,
3674 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 };
3675 const u8 x[16] = {
3676 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3677 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3678 const u8 y[16] = {
3679 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3680 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3681 const u32 exp_val = 0x2f9ed5ba % 1000000;
3682 u32 val;
3683 int err;
3685 err = smp_g2(tfm_cmac, u, v, x, y, &val);
3686 if (err)
3687 return err;
3689 if (val != exp_val)
3690 return -EINVAL;
3692 return 0;
3695 static int __init test_h6(struct crypto_shash *tfm_cmac)
3697 const u8 w[16] = {
3698 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3699 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3700 const u8 key_id[4] = { 0x72, 0x62, 0x65, 0x6c };
3701 const u8 exp[16] = {
3702 0x99, 0x63, 0xb1, 0x80, 0xe2, 0xa9, 0xd3, 0xe8,
3703 0x1c, 0xc9, 0x6d, 0xe7, 0x02, 0xe1, 0x9a, 0x2d };
3704 u8 res[16];
3705 int err;
3707 err = smp_h6(tfm_cmac, w, key_id, res);
3708 if (err)
3709 return err;
3711 if (memcmp(res, exp, 16))
3712 return -EINVAL;
3714 return 0;
3717 static char test_smp_buffer[32];
3719 static ssize_t test_smp_read(struct file *file, char __user *user_buf,
3720 size_t count, loff_t *ppos)
3722 return simple_read_from_buffer(user_buf, count, ppos, test_smp_buffer,
3723 strlen(test_smp_buffer));
3726 static const struct file_operations test_smp_fops = {
3727 .open = simple_open,
3728 .read = test_smp_read,
3729 .llseek = default_llseek,
3732 static int __init run_selftests(struct crypto_cipher *tfm_aes,
3733 struct crypto_shash *tfm_cmac)
3735 ktime_t calltime, delta, rettime;
3736 unsigned long long duration;
3737 int err;
3739 calltime = ktime_get();
3741 err = test_ah(tfm_aes);
3742 if (err) {
3743 BT_ERR("smp_ah test failed");
3744 goto done;
3747 err = test_c1(tfm_aes);
3748 if (err) {
3749 BT_ERR("smp_c1 test failed");
3750 goto done;
3753 err = test_s1(tfm_aes);
3754 if (err) {
3755 BT_ERR("smp_s1 test failed");
3756 goto done;
3759 err = test_f4(tfm_cmac);
3760 if (err) {
3761 BT_ERR("smp_f4 test failed");
3762 goto done;
3765 err = test_f5(tfm_cmac);
3766 if (err) {
3767 BT_ERR("smp_f5 test failed");
3768 goto done;
3771 err = test_f6(tfm_cmac);
3772 if (err) {
3773 BT_ERR("smp_f6 test failed");
3774 goto done;
3777 err = test_g2(tfm_cmac);
3778 if (err) {
3779 BT_ERR("smp_g2 test failed");
3780 goto done;
3783 err = test_h6(tfm_cmac);
3784 if (err) {
3785 BT_ERR("smp_h6 test failed");
3786 goto done;
3789 rettime = ktime_get();
3790 delta = ktime_sub(rettime, calltime);
3791 duration = (unsigned long long) ktime_to_ns(delta) >> 10;
3793 BT_INFO("SMP test passed in %llu usecs", duration);
3795 done:
3796 if (!err)
3797 snprintf(test_smp_buffer, sizeof(test_smp_buffer),
3798 "PASS (%llu usecs)\n", duration);
3799 else
3800 snprintf(test_smp_buffer, sizeof(test_smp_buffer), "FAIL\n");
3802 debugfs_create_file("selftest_smp", 0444, bt_debugfs, NULL,
3803 &test_smp_fops);
3805 return err;
3808 int __init bt_selftest_smp(void)
3810 struct crypto_cipher *tfm_aes;
3811 struct crypto_shash *tfm_cmac;
3812 int err;
3814 tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
3815 if (IS_ERR(tfm_aes)) {
3816 BT_ERR("Unable to create AES crypto context");
3817 return PTR_ERR(tfm_aes);
3820 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, CRYPTO_ALG_ASYNC);
3821 if (IS_ERR(tfm_cmac)) {
3822 BT_ERR("Unable to create CMAC crypto context");
3823 crypto_free_cipher(tfm_aes);
3824 return PTR_ERR(tfm_cmac);
3827 err = run_selftests(tfm_aes, tfm_cmac);
3829 crypto_free_shash(tfm_cmac);
3830 crypto_free_cipher(tfm_aes);
3832 return err;
3835 #endif