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/crypto.h>
24 #include <linux/scatterlist.h>
25 #include <crypto/b128ops.h>
27 #include <net/bluetooth/bluetooth.h>
28 #include <net/bluetooth/hci_core.h>
29 #include <net/bluetooth/l2cap.h>
30 #include <net/bluetooth/mgmt.h>
35 #define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd)
37 /* Keys which are not distributed with Secure Connections */
38 #define SMP_SC_NO_DIST (SMP_DIST_ENC_KEY | SMP_DIST_LINK_KEY);
40 #define SMP_TIMEOUT msecs_to_jiffies(30000)
42 #define AUTH_REQ_MASK(dev) (test_bit(HCI_SC_ENABLED, &(dev)->dev_flags) ? \
44 #define KEY_DIST_MASK 0x07
46 /* Maximum message length that can be passed to aes_cmac */
47 #define CMAC_MSG_MAX 80
61 struct l2cap_conn *conn;
62 struct delayed_work security_timer;
63 unsigned long allow_cmd; /* Bitmask of allowed commands */
65 u8 preq[7]; /* SMP Pairing Request */
66 u8 prsp[7]; /* SMP Pairing Response */
67 u8 prnd[16]; /* SMP Pairing Random (local) */
68 u8 rrnd[16]; /* SMP Pairing Random (remote) */
69 u8 pcnf[16]; /* SMP Pairing Confirm */
70 u8 tk[16]; /* SMP Temporary Key */
76 struct smp_csrk *csrk;
77 struct smp_csrk *slave_csrk;
79 struct smp_ltk *slave_ltk;
80 struct smp_irk *remote_irk;
85 /* Secure Connections variables */
92 struct crypto_blkcipher *tfm_aes;
93 struct crypto_hash *tfm_cmac;
96 /* These debug key values are defined in the SMP section of the core
97 * specification. debug_pk is the public debug key and debug_sk the
100 static const u8 debug_pk[64] = {
101 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
102 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
103 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
104 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20,
106 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74,
107 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76,
108 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63,
109 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc,
112 static const u8 debug_sk[32] = {
113 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58,
114 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a,
115 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74,
116 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f,
119 static inline void swap_buf(const u8 *src, u8 *dst, size_t len)
123 for (i = 0; i < len; i++)
124 dst[len - 1 - i] = src[i];
127 static int aes_cmac(struct crypto_hash *tfm, const u8 k[16], const u8 *m,
128 size_t len, u8 mac[16])
130 uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX];
131 struct hash_desc desc;
132 struct scatterlist sg;
135 if (len > CMAC_MSG_MAX)
139 BT_ERR("tfm %p", tfm);
146 crypto_hash_init(&desc);
148 /* Swap key and message from LSB to MSB */
149 swap_buf(k, tmp, 16);
150 swap_buf(m, msg_msb, len);
152 BT_DBG("msg (len %zu) %*phN", len, (int) len, m);
153 BT_DBG("key %16phN", k);
155 err = crypto_hash_setkey(tfm, tmp, 16);
157 BT_ERR("cipher setkey failed: %d", err);
161 sg_init_one(&sg, msg_msb, len);
163 err = crypto_hash_update(&desc, &sg, len);
165 BT_ERR("Hash update error %d", err);
169 err = crypto_hash_final(&desc, mac_msb);
171 BT_ERR("Hash final error %d", err);
175 swap_buf(mac_msb, mac, 16);
177 BT_DBG("mac %16phN", mac);
182 static int smp_f4(struct crypto_hash *tfm_cmac, const u8 u[32], const u8 v[32],
183 const u8 x[16], u8 z, u8 res[16])
188 BT_DBG("u %32phN", u);
189 BT_DBG("v %32phN", v);
190 BT_DBG("x %16phN z %02x", x, z);
193 memcpy(m + 1, v, 32);
194 memcpy(m + 33, u, 32);
196 err = aes_cmac(tfm_cmac, x, m, sizeof(m), res);
200 BT_DBG("res %16phN", res);
205 static int smp_f5(struct crypto_hash *tfm_cmac, u8 w[32], u8 n1[16], u8 n2[16],
206 u8 a1[7], u8 a2[7], u8 mackey[16], u8 ltk[16])
208 /* The btle, salt and length "magic" values are as defined in
209 * the SMP section of the Bluetooth core specification. In ASCII
210 * the btle value ends up being 'btle'. The salt is just a
211 * random number whereas length is the value 256 in little
214 const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 };
215 const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60,
216 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c };
217 const u8 length[2] = { 0x00, 0x01 };
221 BT_DBG("w %32phN", w);
222 BT_DBG("n1 %16phN n2 %16phN", n1, n2);
223 BT_DBG("a1 %7phN a2 %7phN", a1, a2);
225 err = aes_cmac(tfm_cmac, salt, w, 32, t);
229 BT_DBG("t %16phN", t);
231 memcpy(m, length, 2);
232 memcpy(m + 2, a2, 7);
233 memcpy(m + 9, a1, 7);
234 memcpy(m + 16, n2, 16);
235 memcpy(m + 32, n1, 16);
236 memcpy(m + 48, btle, 4);
238 m[52] = 0; /* Counter */
240 err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey);
244 BT_DBG("mackey %16phN", mackey);
246 m[52] = 1; /* Counter */
248 err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk);
252 BT_DBG("ltk %16phN", ltk);
257 static int smp_f6(struct crypto_hash *tfm_cmac, const u8 w[16],
258 const u8 n1[16], u8 n2[16], const u8 r[16],
259 const u8 io_cap[3], const u8 a1[7], const u8 a2[7],
265 BT_DBG("w %16phN", w);
266 BT_DBG("n1 %16phN n2 %16phN", n1, n2);
267 BT_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2);
270 memcpy(m + 7, a1, 7);
271 memcpy(m + 14, io_cap, 3);
272 memcpy(m + 17, r, 16);
273 memcpy(m + 33, n2, 16);
274 memcpy(m + 49, n1, 16);
276 err = aes_cmac(tfm_cmac, w, m, sizeof(m), res);
280 BT_DBG("res %16phN", res);
285 static int smp_g2(struct crypto_hash *tfm_cmac, const u8 u[32], const u8 v[32],
286 const u8 x[16], const u8 y[16], u32 *val)
291 BT_DBG("u %32phN", u);
292 BT_DBG("v %32phN", v);
293 BT_DBG("x %16phN y %16phN", x, y);
296 memcpy(m + 16, v, 32);
297 memcpy(m + 48, u, 32);
299 err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp);
303 *val = get_unaligned_le32(tmp);
306 BT_DBG("val %06u", *val);
311 static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r)
313 struct blkcipher_desc desc;
314 struct scatterlist sg;
315 uint8_t tmp[16], data[16];
319 BT_ERR("tfm %p", tfm);
326 /* The most significant octet of key corresponds to k[0] */
327 swap_buf(k, tmp, 16);
329 err = crypto_blkcipher_setkey(tfm, tmp, 16);
331 BT_ERR("cipher setkey failed: %d", err);
335 /* Most significant octet of plaintextData corresponds to data[0] */
336 swap_buf(r, data, 16);
338 sg_init_one(&sg, data, 16);
340 err = crypto_blkcipher_encrypt(&desc, &sg, &sg, 16);
342 BT_ERR("Encrypt data error %d", err);
344 /* Most significant octet of encryptedData corresponds to data[0] */
345 swap_buf(data, r, 16);
350 static int smp_h6(struct crypto_hash *tfm_cmac, const u8 w[16],
351 const u8 key_id[4], u8 res[16])
355 BT_DBG("w %16phN key_id %4phN", w, key_id);
357 err = aes_cmac(tfm_cmac, w, key_id, 4, res);
361 BT_DBG("res %16phN", res);
366 static int smp_ah(struct crypto_blkcipher *tfm, u8 irk[16], u8 r[3], u8 res[3])
371 /* r' = padding || r */
373 memset(_res + 3, 0, 13);
375 err = smp_e(tfm, irk, _res);
377 BT_ERR("Encrypt error");
381 /* The output of the random address function ah is:
382 * ah(h, r) = e(k, r') mod 2^24
383 * The output of the security function e is then truncated to 24 bits
384 * by taking the least significant 24 bits of the output of e as the
387 memcpy(res, _res, 3);
392 bool smp_irk_matches(struct hci_dev *hdev, u8 irk[16], bdaddr_t *bdaddr)
394 struct l2cap_chan *chan = hdev->smp_data;
395 struct crypto_blkcipher *tfm;
399 if (!chan || !chan->data)
404 BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk);
406 err = smp_ah(tfm, irk, &bdaddr->b[3], hash);
410 return !memcmp(bdaddr->b, hash, 3);
413 int smp_generate_rpa(struct hci_dev *hdev, u8 irk[16], bdaddr_t *rpa)
415 struct l2cap_chan *chan = hdev->smp_data;
416 struct crypto_blkcipher *tfm;
419 if (!chan || !chan->data)
424 get_random_bytes(&rpa->b[3], 3);
426 rpa->b[5] &= 0x3f; /* Clear two most significant bits */
427 rpa->b[5] |= 0x40; /* Set second most significant bit */
429 err = smp_ah(tfm, irk, &rpa->b[3], rpa->b);
433 BT_DBG("RPA %pMR", rpa);
438 static int smp_c1(struct crypto_blkcipher *tfm_aes, u8 k[16], u8 r[16],
439 u8 preq[7], u8 pres[7], u8 _iat, bdaddr_t *ia, u8 _rat,
440 bdaddr_t *ra, u8 res[16])
447 /* p1 = pres || preq || _rat || _iat */
450 memcpy(p1 + 2, preq, 7);
451 memcpy(p1 + 9, pres, 7);
453 /* p2 = padding || ia || ra */
455 memcpy(p2 + 6, ia, 6);
456 memset(p2 + 12, 0, 4);
459 u128_xor((u128 *) res, (u128 *) r, (u128 *) p1);
461 /* res = e(k, res) */
462 err = smp_e(tfm_aes, k, res);
464 BT_ERR("Encrypt data error");
468 /* res = res XOR p2 */
469 u128_xor((u128 *) res, (u128 *) res, (u128 *) p2);
471 /* res = e(k, res) */
472 err = smp_e(tfm_aes, k, res);
474 BT_ERR("Encrypt data error");
479 static int smp_s1(struct crypto_blkcipher *tfm_aes, u8 k[16], u8 r1[16],
480 u8 r2[16], u8 _r[16])
484 /* Just least significant octets from r1 and r2 are considered */
486 memcpy(_r + 8, r1, 8);
488 err = smp_e(tfm_aes, k, _r);
490 BT_ERR("Encrypt data error");
495 static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
497 struct l2cap_chan *chan = conn->smp;
498 struct smp_chan *smp;
505 BT_DBG("code 0x%2.2x", code);
507 iv[0].iov_base = &code;
510 iv[1].iov_base = data;
513 memset(&msg, 0, sizeof(msg));
515 msg.msg_iov = (struct iovec *) &iv;
518 l2cap_chan_send(chan, &msg, 1 + len);
525 cancel_delayed_work_sync(&smp->security_timer);
526 schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT);
529 static u8 authreq_to_seclevel(u8 authreq)
531 if (authreq & SMP_AUTH_MITM) {
532 if (authreq & SMP_AUTH_SC)
533 return BT_SECURITY_FIPS;
535 return BT_SECURITY_HIGH;
537 return BT_SECURITY_MEDIUM;
541 static __u8 seclevel_to_authreq(__u8 sec_level)
544 case BT_SECURITY_FIPS:
545 case BT_SECURITY_HIGH:
546 return SMP_AUTH_MITM | SMP_AUTH_BONDING;
547 case BT_SECURITY_MEDIUM:
548 return SMP_AUTH_BONDING;
550 return SMP_AUTH_NONE;
554 static void build_pairing_cmd(struct l2cap_conn *conn,
555 struct smp_cmd_pairing *req,
556 struct smp_cmd_pairing *rsp, __u8 authreq)
558 struct l2cap_chan *chan = conn->smp;
559 struct smp_chan *smp = chan->data;
560 struct hci_conn *hcon = conn->hcon;
561 struct hci_dev *hdev = hcon->hdev;
562 u8 local_dist = 0, remote_dist = 0;
564 if (test_bit(HCI_BONDABLE, &conn->hcon->hdev->dev_flags)) {
565 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
566 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
567 authreq |= SMP_AUTH_BONDING;
569 authreq &= ~SMP_AUTH_BONDING;
572 if (test_bit(HCI_RPA_RESOLVING, &hdev->dev_flags))
573 remote_dist |= SMP_DIST_ID_KEY;
575 if (test_bit(HCI_PRIVACY, &hdev->dev_flags))
576 local_dist |= SMP_DIST_ID_KEY;
578 if (test_bit(HCI_SC_ENABLED, &hdev->dev_flags)) {
579 if ((authreq & SMP_AUTH_SC) &&
580 test_bit(HCI_SSP_ENABLED, &hdev->dev_flags)) {
581 local_dist |= SMP_DIST_LINK_KEY;
582 remote_dist |= SMP_DIST_LINK_KEY;
585 authreq &= ~SMP_AUTH_SC;
589 req->io_capability = conn->hcon->io_capability;
590 req->oob_flag = SMP_OOB_NOT_PRESENT;
591 req->max_key_size = SMP_MAX_ENC_KEY_SIZE;
592 req->init_key_dist = local_dist;
593 req->resp_key_dist = remote_dist;
594 req->auth_req = (authreq & AUTH_REQ_MASK(hdev));
596 smp->remote_key_dist = remote_dist;
600 rsp->io_capability = conn->hcon->io_capability;
601 rsp->oob_flag = SMP_OOB_NOT_PRESENT;
602 rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
603 rsp->init_key_dist = req->init_key_dist & remote_dist;
604 rsp->resp_key_dist = req->resp_key_dist & local_dist;
605 rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev));
607 smp->remote_key_dist = rsp->init_key_dist;
610 static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)
612 struct l2cap_chan *chan = conn->smp;
613 struct smp_chan *smp = chan->data;
615 if ((max_key_size > SMP_MAX_ENC_KEY_SIZE) ||
616 (max_key_size < SMP_MIN_ENC_KEY_SIZE))
617 return SMP_ENC_KEY_SIZE;
619 smp->enc_key_size = max_key_size;
624 static void smp_chan_destroy(struct l2cap_conn *conn)
626 struct l2cap_chan *chan = conn->smp;
627 struct smp_chan *smp = chan->data;
632 cancel_delayed_work_sync(&smp->security_timer);
634 complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags);
635 mgmt_smp_complete(conn->hcon, complete);
638 kfree(smp->slave_csrk);
639 kfree(smp->link_key);
641 crypto_free_blkcipher(smp->tfm_aes);
642 crypto_free_hash(smp->tfm_cmac);
644 /* If pairing failed clean up any keys we might have */
647 list_del_rcu(&smp->ltk->list);
648 kfree_rcu(smp->ltk, rcu);
651 if (smp->slave_ltk) {
652 list_del_rcu(&smp->slave_ltk->list);
653 kfree_rcu(smp->slave_ltk, rcu);
656 if (smp->remote_irk) {
657 list_del_rcu(&smp->remote_irk->list);
658 kfree_rcu(smp->remote_irk, rcu);
664 hci_conn_drop(conn->hcon);
667 static void smp_failure(struct l2cap_conn *conn, u8 reason)
669 struct hci_conn *hcon = conn->hcon;
670 struct l2cap_chan *chan = conn->smp;
673 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
676 clear_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags);
677 mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE);
680 smp_chan_destroy(conn);
683 #define JUST_WORKS 0x00
684 #define JUST_CFM 0x01
685 #define REQ_PASSKEY 0x02
686 #define CFM_PASSKEY 0x03
688 #define DSP_PASSKEY 0x05
691 static const u8 gen_method[5][5] = {
692 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
693 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
694 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
695 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
696 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP },
699 static const u8 sc_method[5][5] = {
700 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
701 { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
702 { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY },
703 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
704 { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
707 static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io)
709 /* If either side has unknown io_caps, use JUST_CFM (which gets
710 * converted later to JUST_WORKS if we're initiators.
712 if (local_io > SMP_IO_KEYBOARD_DISPLAY ||
713 remote_io > SMP_IO_KEYBOARD_DISPLAY)
716 if (test_bit(SMP_FLAG_SC, &smp->flags))
717 return sc_method[remote_io][local_io];
719 return gen_method[remote_io][local_io];
722 static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
723 u8 local_io, u8 remote_io)
725 struct hci_conn *hcon = conn->hcon;
726 struct l2cap_chan *chan = conn->smp;
727 struct smp_chan *smp = chan->data;
731 /* Initialize key for JUST WORKS */
732 memset(smp->tk, 0, sizeof(smp->tk));
733 clear_bit(SMP_FLAG_TK_VALID, &smp->flags);
735 BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io);
737 /* If neither side wants MITM, either "just" confirm an incoming
738 * request or use just-works for outgoing ones. The JUST_CFM
739 * will be converted to JUST_WORKS if necessary later in this
740 * function. If either side has MITM look up the method from the
743 if (!(auth & SMP_AUTH_MITM))
744 smp->method = JUST_CFM;
746 smp->method = get_auth_method(smp, local_io, remote_io);
748 /* Don't confirm locally initiated pairing attempts */
749 if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR,
751 smp->method = JUST_WORKS;
753 /* Don't bother user space with no IO capabilities */
754 if (smp->method == JUST_CFM &&
755 hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
756 smp->method = JUST_WORKS;
758 /* If Just Works, Continue with Zero TK */
759 if (smp->method == JUST_WORKS) {
760 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
764 /* Not Just Works/Confirm results in MITM Authentication */
765 if (smp->method != JUST_CFM) {
766 set_bit(SMP_FLAG_MITM_AUTH, &smp->flags);
767 if (hcon->pending_sec_level < BT_SECURITY_HIGH)
768 hcon->pending_sec_level = BT_SECURITY_HIGH;
771 /* If both devices have Keyoard-Display I/O, the master
772 * Confirms and the slave Enters the passkey.
774 if (smp->method == OVERLAP) {
775 if (hcon->role == HCI_ROLE_MASTER)
776 smp->method = CFM_PASSKEY;
778 smp->method = REQ_PASSKEY;
781 /* Generate random passkey. */
782 if (smp->method == CFM_PASSKEY) {
783 memset(smp->tk, 0, sizeof(smp->tk));
784 get_random_bytes(&passkey, sizeof(passkey));
786 put_unaligned_le32(passkey, smp->tk);
787 BT_DBG("PassKey: %d", passkey);
788 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
791 if (smp->method == REQ_PASSKEY)
792 ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst,
793 hcon->type, hcon->dst_type);
794 else if (smp->method == JUST_CFM)
795 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
796 hcon->type, hcon->dst_type,
799 ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst,
800 hcon->type, hcon->dst_type,
806 static u8 smp_confirm(struct smp_chan *smp)
808 struct l2cap_conn *conn = smp->conn;
809 struct smp_cmd_pairing_confirm cp;
812 BT_DBG("conn %p", conn);
814 ret = smp_c1(smp->tfm_aes, smp->tk, smp->prnd, smp->preq, smp->prsp,
815 conn->hcon->init_addr_type, &conn->hcon->init_addr,
816 conn->hcon->resp_addr_type, &conn->hcon->resp_addr,
819 return SMP_UNSPECIFIED;
821 clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
823 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
826 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
828 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
833 static u8 smp_random(struct smp_chan *smp)
835 struct l2cap_conn *conn = smp->conn;
836 struct hci_conn *hcon = conn->hcon;
840 if (IS_ERR_OR_NULL(smp->tfm_aes))
841 return SMP_UNSPECIFIED;
843 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
845 ret = smp_c1(smp->tfm_aes, smp->tk, smp->rrnd, smp->preq, smp->prsp,
846 hcon->init_addr_type, &hcon->init_addr,
847 hcon->resp_addr_type, &hcon->resp_addr, confirm);
849 return SMP_UNSPECIFIED;
851 if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) {
852 BT_ERR("Pairing failed (confirmation values mismatch)");
853 return SMP_CONFIRM_FAILED;
861 smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk);
863 memset(stk + smp->enc_key_size, 0,
864 SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size);
866 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
867 return SMP_UNSPECIFIED;
869 hci_le_start_enc(hcon, ediv, rand, stk);
870 hcon->enc_key_size = smp->enc_key_size;
871 set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
877 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
880 smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk);
882 memset(stk + smp->enc_key_size, 0,
883 SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size);
885 if (hcon->pending_sec_level == BT_SECURITY_HIGH)
890 /* Even though there's no _SLAVE suffix this is the
891 * slave STK we're adding for later lookup (the master
892 * STK never needs to be stored).
894 hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
895 SMP_STK, auth, stk, smp->enc_key_size, ediv, rand);
901 static void smp_notify_keys(struct l2cap_conn *conn)
903 struct l2cap_chan *chan = conn->smp;
904 struct smp_chan *smp = chan->data;
905 struct hci_conn *hcon = conn->hcon;
906 struct hci_dev *hdev = hcon->hdev;
907 struct smp_cmd_pairing *req = (void *) &smp->preq[1];
908 struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1];
911 if (smp->remote_irk) {
912 mgmt_new_irk(hdev, smp->remote_irk);
913 /* Now that user space can be considered to know the
914 * identity address track the connection based on it
917 bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
918 hcon->dst_type = smp->remote_irk->addr_type;
919 queue_work(hdev->workqueue, &conn->id_addr_update_work);
921 /* When receiving an indentity resolving key for
922 * a remote device that does not use a resolvable
923 * private address, just remove the key so that
924 * it is possible to use the controller white
927 * Userspace will have been told to not store
928 * this key at this point. So it is safe to
931 if (!bacmp(&smp->remote_irk->rpa, BDADDR_ANY)) {
932 list_del_rcu(&smp->remote_irk->list);
933 kfree_rcu(smp->remote_irk, rcu);
934 smp->remote_irk = NULL;
938 /* The LTKs and CSRKs should be persistent only if both sides
939 * had the bonding bit set in their authentication requests.
941 persistent = !!((req->auth_req & rsp->auth_req) & SMP_AUTH_BONDING);
944 smp->csrk->bdaddr_type = hcon->dst_type;
945 bacpy(&smp->csrk->bdaddr, &hcon->dst);
946 mgmt_new_csrk(hdev, smp->csrk, persistent);
949 if (smp->slave_csrk) {
950 smp->slave_csrk->bdaddr_type = hcon->dst_type;
951 bacpy(&smp->slave_csrk->bdaddr, &hcon->dst);
952 mgmt_new_csrk(hdev, smp->slave_csrk, persistent);
956 smp->ltk->bdaddr_type = hcon->dst_type;
957 bacpy(&smp->ltk->bdaddr, &hcon->dst);
958 mgmt_new_ltk(hdev, smp->ltk, persistent);
961 if (smp->slave_ltk) {
962 smp->slave_ltk->bdaddr_type = hcon->dst_type;
963 bacpy(&smp->slave_ltk->bdaddr, &hcon->dst);
964 mgmt_new_ltk(hdev, smp->slave_ltk, persistent);
968 hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst,
969 smp->link_key, HCI_LK_AUTH_COMBINATION_P256,
974 static void sc_generate_link_key(struct smp_chan *smp)
976 /* These constants are as specified in the core specification.
977 * In ASCII they spell out to 'tmp1' and 'lebr'.
979 const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 };
980 const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c };
982 smp->link_key = kzalloc(16, GFP_KERNEL);
986 if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) {
987 kfree(smp->link_key);
988 smp->link_key = NULL;
992 if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) {
993 kfree(smp->link_key);
994 smp->link_key = NULL;
999 static void smp_allow_key_dist(struct smp_chan *smp)
1001 /* Allow the first expected phase 3 PDU. The rest of the PDUs
1002 * will be allowed in each PDU handler to ensure we receive
1003 * them in the correct order.
1005 if (smp->remote_key_dist & SMP_DIST_ENC_KEY)
1006 SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO);
1007 else if (smp->remote_key_dist & SMP_DIST_ID_KEY)
1008 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
1009 else if (smp->remote_key_dist & SMP_DIST_SIGN)
1010 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
1013 static void smp_distribute_keys(struct smp_chan *smp)
1015 struct smp_cmd_pairing *req, *rsp;
1016 struct l2cap_conn *conn = smp->conn;
1017 struct hci_conn *hcon = conn->hcon;
1018 struct hci_dev *hdev = hcon->hdev;
1021 BT_DBG("conn %p", conn);
1023 rsp = (void *) &smp->prsp[1];
1025 /* The responder sends its keys first */
1026 if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) {
1027 smp_allow_key_dist(smp);
1031 req = (void *) &smp->preq[1];
1034 keydist = &rsp->init_key_dist;
1035 *keydist &= req->init_key_dist;
1037 keydist = &rsp->resp_key_dist;
1038 *keydist &= req->resp_key_dist;
1041 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1042 if (*keydist & SMP_DIST_LINK_KEY)
1043 sc_generate_link_key(smp);
1045 /* Clear the keys which are generated but not distributed */
1046 *keydist &= ~SMP_SC_NO_DIST;
1049 BT_DBG("keydist 0x%x", *keydist);
1051 if (*keydist & SMP_DIST_ENC_KEY) {
1052 struct smp_cmd_encrypt_info enc;
1053 struct smp_cmd_master_ident ident;
1054 struct smp_ltk *ltk;
1059 get_random_bytes(enc.ltk, sizeof(enc.ltk));
1060 get_random_bytes(&ediv, sizeof(ediv));
1061 get_random_bytes(&rand, sizeof(rand));
1063 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);
1065 authenticated = hcon->sec_level == BT_SECURITY_HIGH;
1066 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type,
1067 SMP_LTK_SLAVE, authenticated, enc.ltk,
1068 smp->enc_key_size, ediv, rand);
1069 smp->slave_ltk = ltk;
1074 smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident);
1076 *keydist &= ~SMP_DIST_ENC_KEY;
1079 if (*keydist & SMP_DIST_ID_KEY) {
1080 struct smp_cmd_ident_addr_info addrinfo;
1081 struct smp_cmd_ident_info idinfo;
1083 memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk));
1085 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);
1087 /* The hci_conn contains the local identity address
1088 * after the connection has been established.
1090 * This is true even when the connection has been
1091 * established using a resolvable random address.
1093 bacpy(&addrinfo.bdaddr, &hcon->src);
1094 addrinfo.addr_type = hcon->src_type;
1096 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo),
1099 *keydist &= ~SMP_DIST_ID_KEY;
1102 if (*keydist & SMP_DIST_SIGN) {
1103 struct smp_cmd_sign_info sign;
1104 struct smp_csrk *csrk;
1106 /* Generate a new random key */
1107 get_random_bytes(sign.csrk, sizeof(sign.csrk));
1109 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
1111 csrk->master = 0x00;
1112 memcpy(csrk->val, sign.csrk, sizeof(csrk->val));
1114 smp->slave_csrk = csrk;
1116 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);
1118 *keydist &= ~SMP_DIST_SIGN;
1121 /* If there are still keys to be received wait for them */
1122 if (smp->remote_key_dist & KEY_DIST_MASK) {
1123 smp_allow_key_dist(smp);
1127 set_bit(SMP_FLAG_COMPLETE, &smp->flags);
1128 smp_notify_keys(conn);
1130 smp_chan_destroy(conn);
1133 static void smp_timeout(struct work_struct *work)
1135 struct smp_chan *smp = container_of(work, struct smp_chan,
1136 security_timer.work);
1137 struct l2cap_conn *conn = smp->conn;
1139 BT_DBG("conn %p", conn);
1141 hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM);
1144 static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
1146 struct l2cap_chan *chan = conn->smp;
1147 struct smp_chan *smp;
1149 smp = kzalloc(sizeof(*smp), GFP_ATOMIC);
1153 smp->tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
1154 if (IS_ERR(smp->tfm_aes)) {
1155 BT_ERR("Unable to create ECB crypto context");
1160 smp->tfm_cmac = crypto_alloc_hash("cmac(aes)", 0, CRYPTO_ALG_ASYNC);
1161 if (IS_ERR(smp->tfm_cmac)) {
1162 BT_ERR("Unable to create CMAC crypto context");
1163 crypto_free_blkcipher(smp->tfm_aes);
1171 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL);
1173 INIT_DELAYED_WORK(&smp->security_timer, smp_timeout);
1175 hci_conn_hold(conn->hcon);
1180 static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16])
1182 struct hci_conn *hcon = smp->conn->hcon;
1183 u8 *na, *nb, a[7], b[7];
1193 memcpy(a, &hcon->init_addr, 6);
1194 memcpy(b, &hcon->resp_addr, 6);
1195 a[6] = hcon->init_addr_type;
1196 b[6] = hcon->resp_addr_type;
1198 return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk);
1201 static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey)
1203 struct hci_conn *hcon = smp->conn->hcon;
1204 struct smp_cmd_dhkey_check check;
1205 u8 a[7], b[7], *local_addr, *remote_addr;
1206 u8 io_cap[3], r[16];
1209 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1210 smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED);
1212 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1213 smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED);
1217 memcpy(a, &hcon->init_addr, 6);
1218 memcpy(b, &hcon->resp_addr, 6);
1219 a[6] = hcon->init_addr_type;
1220 b[6] = hcon->resp_addr_type;
1225 memcpy(io_cap, &smp->preq[1], 3);
1229 memcpy(io_cap, &smp->prsp[1], 3);
1232 memcpy(r, &passkey, sizeof(passkey));
1233 memset(r + sizeof(passkey), 0, sizeof(r) - sizeof(passkey));
1235 smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap,
1236 local_addr, remote_addr, check.e);
1238 smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check);
1243 int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
1245 struct l2cap_conn *conn = hcon->l2cap_data;
1246 struct l2cap_chan *chan;
1247 struct smp_chan *smp;
1260 l2cap_chan_lock(chan);
1268 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1269 err = sc_user_reply(smp, mgmt_op, passkey);
1274 case MGMT_OP_USER_PASSKEY_REPLY:
1275 value = le32_to_cpu(passkey);
1276 memset(smp->tk, 0, sizeof(smp->tk));
1277 BT_DBG("PassKey: %d", value);
1278 put_unaligned_le32(value, smp->tk);
1280 case MGMT_OP_USER_CONFIRM_REPLY:
1281 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
1283 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1284 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1285 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1289 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1296 /* If it is our turn to send Pairing Confirm, do so now */
1297 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) {
1298 u8 rsp = smp_confirm(smp);
1300 smp_failure(conn, rsp);
1304 l2cap_chan_unlock(chan);
1308 static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
1310 struct smp_cmd_pairing rsp, *req = (void *) skb->data;
1311 struct l2cap_chan *chan = conn->smp;
1312 struct hci_dev *hdev = conn->hcon->hdev;
1313 struct smp_chan *smp;
1314 u8 key_size, auth, sec_level;
1317 BT_DBG("conn %p", conn);
1319 if (skb->len < sizeof(*req))
1320 return SMP_INVALID_PARAMS;
1322 if (conn->hcon->role != HCI_ROLE_SLAVE)
1323 return SMP_CMD_NOTSUPP;
1326 smp = smp_chan_create(conn);
1331 return SMP_UNSPECIFIED;
1333 /* We didn't start the pairing, so match remote */
1334 auth = req->auth_req & AUTH_REQ_MASK(hdev);
1336 if (!test_bit(HCI_BONDABLE, &hdev->dev_flags) &&
1337 (auth & SMP_AUTH_BONDING))
1338 return SMP_PAIRING_NOTSUPP;
1340 smp->preq[0] = SMP_CMD_PAIRING_REQ;
1341 memcpy(&smp->preq[1], req, sizeof(*req));
1342 skb_pull(skb, sizeof(*req));
1344 build_pairing_cmd(conn, req, &rsp, auth);
1346 if (rsp.auth_req & SMP_AUTH_SC)
1347 set_bit(SMP_FLAG_SC, &smp->flags);
1349 if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
1350 sec_level = BT_SECURITY_MEDIUM;
1352 sec_level = authreq_to_seclevel(auth);
1354 if (sec_level > conn->hcon->pending_sec_level)
1355 conn->hcon->pending_sec_level = sec_level;
1357 /* If we need MITM check that it can be achieved */
1358 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1361 method = get_auth_method(smp, conn->hcon->io_capability,
1362 req->io_capability);
1363 if (method == JUST_WORKS || method == JUST_CFM)
1364 return SMP_AUTH_REQUIREMENTS;
1367 key_size = min(req->max_key_size, rsp.max_key_size);
1368 if (check_enc_key_size(conn, key_size))
1369 return SMP_ENC_KEY_SIZE;
1371 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1373 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1374 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1376 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1378 clear_bit(SMP_FLAG_INITIATOR, &smp->flags);
1380 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1381 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
1382 /* Clear bits which are generated but not distributed */
1383 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1384 /* Wait for Public Key from Initiating Device */
1387 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1390 /* Request setup of TK */
1391 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability);
1393 return SMP_UNSPECIFIED;
1398 static u8 sc_send_public_key(struct smp_chan *smp)
1403 /* Generate local key pair for Secure Connections */
1404 if (!ecc_make_key(smp->local_pk, smp->local_sk))
1405 return SMP_UNSPECIFIED;
1407 /* This is unlikely, but we need to check that we didn't
1408 * accidentially generate a debug key.
1410 if (memcmp(smp->local_sk, debug_sk, 32))
1414 BT_DBG("Local Public Key X: %32phN", smp->local_pk);
1415 BT_DBG("Local Public Key Y: %32phN", &smp->local_pk[32]);
1416 BT_DBG("Local Private Key: %32phN", smp->local_sk);
1418 smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk);
1423 static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
1425 struct smp_cmd_pairing *req, *rsp = (void *) skb->data;
1426 struct l2cap_chan *chan = conn->smp;
1427 struct smp_chan *smp = chan->data;
1428 struct hci_dev *hdev = conn->hcon->hdev;
1432 BT_DBG("conn %p", conn);
1434 if (skb->len < sizeof(*rsp))
1435 return SMP_INVALID_PARAMS;
1437 if (conn->hcon->role != HCI_ROLE_MASTER)
1438 return SMP_CMD_NOTSUPP;
1440 skb_pull(skb, sizeof(*rsp));
1442 req = (void *) &smp->preq[1];
1444 key_size = min(req->max_key_size, rsp->max_key_size);
1445 if (check_enc_key_size(conn, key_size))
1446 return SMP_ENC_KEY_SIZE;
1448 auth = rsp->auth_req & AUTH_REQ_MASK(hdev);
1450 if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC))
1451 set_bit(SMP_FLAG_SC, &smp->flags);
1452 else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH)
1453 conn->hcon->pending_sec_level = BT_SECURITY_HIGH;
1455 /* If we need MITM check that it can be achieved */
1456 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1459 method = get_auth_method(smp, req->io_capability,
1460 rsp->io_capability);
1461 if (method == JUST_WORKS || method == JUST_CFM)
1462 return SMP_AUTH_REQUIREMENTS;
1465 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1467 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1468 memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
1470 /* Update remote key distribution in case the remote cleared
1471 * some bits that we had enabled in our request.
1473 smp->remote_key_dist &= rsp->resp_key_dist;
1475 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1476 /* Clear bits which are generated but not distributed */
1477 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1478 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
1479 return sc_send_public_key(smp);
1482 auth |= req->auth_req;
1484 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability);
1486 return SMP_UNSPECIFIED;
1488 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
1490 /* Can't compose response until we have been confirmed */
1491 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
1492 return smp_confirm(smp);
1497 static u8 sc_check_confirm(struct smp_chan *smp)
1499 struct l2cap_conn *conn = smp->conn;
1503 /* Public Key exchange must happen before any other steps */
1504 if (!test_bit(SMP_FLAG_REMOTE_PK, &smp->flags))
1505 return SMP_UNSPECIFIED;
1507 if (conn->hcon->out) {
1508 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1510 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1516 static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
1518 struct l2cap_chan *chan = conn->smp;
1519 struct smp_chan *smp = chan->data;
1521 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
1523 if (skb->len < sizeof(smp->pcnf))
1524 return SMP_INVALID_PARAMS;
1526 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
1527 skb_pull(skb, sizeof(smp->pcnf));
1529 if (test_bit(SMP_FLAG_SC, &smp->flags))
1530 return sc_check_confirm(smp);
1532 if (conn->hcon->out) {
1533 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1535 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1539 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
1540 return smp_confirm(smp);
1542 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
1547 static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
1549 struct l2cap_chan *chan = conn->smp;
1550 struct smp_chan *smp = chan->data;
1551 struct hci_conn *hcon = conn->hcon;
1552 u8 *pkax, *pkbx, *na, *nb;
1556 BT_DBG("conn %p", conn);
1558 if (skb->len < sizeof(smp->rrnd))
1559 return SMP_INVALID_PARAMS;
1561 memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd));
1562 skb_pull(skb, sizeof(smp->rrnd));
1564 if (!test_bit(SMP_FLAG_SC, &smp->flags))
1565 return smp_random(smp);
1570 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
1573 return SMP_UNSPECIFIED;
1575 if (memcmp(smp->pcnf, cfm, 16))
1576 return SMP_CONFIRM_FAILED;
1578 pkax = smp->local_pk;
1579 pkbx = smp->remote_pk;
1583 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1585 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1587 pkax = smp->remote_pk;
1588 pkbx = smp->local_pk;
1593 /* Generate MacKey and LTK */
1594 err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk);
1596 return SMP_UNSPECIFIED;
1598 err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);
1600 return SMP_UNSPECIFIED;
1602 err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
1603 hcon->type, hcon->dst_type,
1606 return SMP_UNSPECIFIED;
1611 static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
1613 struct smp_ltk *key;
1614 struct hci_conn *hcon = conn->hcon;
1616 key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role);
1620 if (smp_ltk_sec_level(key) < sec_level)
1623 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
1626 hci_le_start_enc(hcon, key->ediv, key->rand, key->val);
1627 hcon->enc_key_size = key->enc_size;
1629 /* We never store STKs for master role, so clear this flag */
1630 clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
1635 bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level,
1636 enum smp_key_pref key_pref)
1638 if (sec_level == BT_SECURITY_LOW)
1641 /* If we're encrypted with an STK but the caller prefers using
1642 * LTK claim insufficient security. This way we allow the
1643 * connection to be re-encrypted with an LTK, even if the LTK
1644 * provides the same level of security. Only exception is if we
1645 * don't have an LTK (e.g. because of key distribution bits).
1647 if (key_pref == SMP_USE_LTK &&
1648 test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) &&
1649 hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role))
1652 if (hcon->sec_level >= sec_level)
1658 static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
1660 struct smp_cmd_security_req *rp = (void *) skb->data;
1661 struct smp_cmd_pairing cp;
1662 struct hci_conn *hcon = conn->hcon;
1663 struct hci_dev *hdev = hcon->hdev;
1664 struct smp_chan *smp;
1667 BT_DBG("conn %p", conn);
1669 if (skb->len < sizeof(*rp))
1670 return SMP_INVALID_PARAMS;
1672 if (hcon->role != HCI_ROLE_MASTER)
1673 return SMP_CMD_NOTSUPP;
1675 auth = rp->auth_req & AUTH_REQ_MASK(hdev);
1677 if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
1678 sec_level = BT_SECURITY_MEDIUM;
1680 sec_level = authreq_to_seclevel(auth);
1682 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
1685 if (sec_level > hcon->pending_sec_level)
1686 hcon->pending_sec_level = sec_level;
1688 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
1691 smp = smp_chan_create(conn);
1693 return SMP_UNSPECIFIED;
1695 if (!test_bit(HCI_BONDABLE, &hcon->hdev->dev_flags) &&
1696 (auth & SMP_AUTH_BONDING))
1697 return SMP_PAIRING_NOTSUPP;
1699 skb_pull(skb, sizeof(*rp));
1701 memset(&cp, 0, sizeof(cp));
1702 build_pairing_cmd(conn, &cp, NULL, auth);
1704 smp->preq[0] = SMP_CMD_PAIRING_REQ;
1705 memcpy(&smp->preq[1], &cp, sizeof(cp));
1707 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
1708 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
1713 int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
1715 struct l2cap_conn *conn = hcon->l2cap_data;
1716 struct l2cap_chan *chan;
1717 struct smp_chan *smp;
1721 BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);
1723 /* This may be NULL if there's an unexpected disconnection */
1729 if (!test_bit(HCI_LE_ENABLED, &hcon->hdev->dev_flags))
1732 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
1735 if (sec_level > hcon->pending_sec_level)
1736 hcon->pending_sec_level = sec_level;
1738 if (hcon->role == HCI_ROLE_MASTER)
1739 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
1742 l2cap_chan_lock(chan);
1744 /* If SMP is already in progress ignore this request */
1750 smp = smp_chan_create(conn);
1756 authreq = seclevel_to_authreq(sec_level);
1758 if (test_bit(HCI_SC_ENABLED, &hcon->hdev->dev_flags))
1759 authreq |= SMP_AUTH_SC;
1761 /* Require MITM if IO Capability allows or the security level
1764 if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT ||
1765 hcon->pending_sec_level > BT_SECURITY_MEDIUM)
1766 authreq |= SMP_AUTH_MITM;
1768 if (hcon->role == HCI_ROLE_MASTER) {
1769 struct smp_cmd_pairing cp;
1771 build_pairing_cmd(conn, &cp, NULL, authreq);
1772 smp->preq[0] = SMP_CMD_PAIRING_REQ;
1773 memcpy(&smp->preq[1], &cp, sizeof(cp));
1775 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
1776 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
1778 struct smp_cmd_security_req cp;
1779 cp.auth_req = authreq;
1780 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
1781 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ);
1784 set_bit(SMP_FLAG_INITIATOR, &smp->flags);
1788 l2cap_chan_unlock(chan);
1792 static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb)
1794 struct smp_cmd_encrypt_info *rp = (void *) skb->data;
1795 struct l2cap_chan *chan = conn->smp;
1796 struct smp_chan *smp = chan->data;
1798 BT_DBG("conn %p", conn);
1800 if (skb->len < sizeof(*rp))
1801 return SMP_INVALID_PARAMS;
1803 SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT);
1805 skb_pull(skb, sizeof(*rp));
1807 memcpy(smp->tk, rp->ltk, sizeof(smp->tk));
1812 static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
1814 struct smp_cmd_master_ident *rp = (void *) skb->data;
1815 struct l2cap_chan *chan = conn->smp;
1816 struct smp_chan *smp = chan->data;
1817 struct hci_dev *hdev = conn->hcon->hdev;
1818 struct hci_conn *hcon = conn->hcon;
1819 struct smp_ltk *ltk;
1822 BT_DBG("conn %p", conn);
1824 if (skb->len < sizeof(*rp))
1825 return SMP_INVALID_PARAMS;
1827 /* Mark the information as received */
1828 smp->remote_key_dist &= ~SMP_DIST_ENC_KEY;
1830 if (smp->remote_key_dist & SMP_DIST_ID_KEY)
1831 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
1832 else if (smp->remote_key_dist & SMP_DIST_SIGN)
1833 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
1835 skb_pull(skb, sizeof(*rp));
1837 authenticated = (hcon->sec_level == BT_SECURITY_HIGH);
1838 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK,
1839 authenticated, smp->tk, smp->enc_key_size,
1840 rp->ediv, rp->rand);
1842 if (!(smp->remote_key_dist & KEY_DIST_MASK))
1843 smp_distribute_keys(smp);
1848 static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb)
1850 struct smp_cmd_ident_info *info = (void *) skb->data;
1851 struct l2cap_chan *chan = conn->smp;
1852 struct smp_chan *smp = chan->data;
1856 if (skb->len < sizeof(*info))
1857 return SMP_INVALID_PARAMS;
1859 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO);
1861 skb_pull(skb, sizeof(*info));
1863 memcpy(smp->irk, info->irk, 16);
1868 static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,
1869 struct sk_buff *skb)
1871 struct smp_cmd_ident_addr_info *info = (void *) skb->data;
1872 struct l2cap_chan *chan = conn->smp;
1873 struct smp_chan *smp = chan->data;
1874 struct hci_conn *hcon = conn->hcon;
1879 if (skb->len < sizeof(*info))
1880 return SMP_INVALID_PARAMS;
1882 /* Mark the information as received */
1883 smp->remote_key_dist &= ~SMP_DIST_ID_KEY;
1885 if (smp->remote_key_dist & SMP_DIST_SIGN)
1886 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
1888 skb_pull(skb, sizeof(*info));
1890 /* Strictly speaking the Core Specification (4.1) allows sending
1891 * an empty address which would force us to rely on just the IRK
1892 * as "identity information". However, since such
1893 * implementations are not known of and in order to not over
1894 * complicate our implementation, simply pretend that we never
1895 * received an IRK for such a device.
1897 if (!bacmp(&info->bdaddr, BDADDR_ANY)) {
1898 BT_ERR("Ignoring IRK with no identity address");
1902 bacpy(&smp->id_addr, &info->bdaddr);
1903 smp->id_addr_type = info->addr_type;
1905 if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type))
1906 bacpy(&rpa, &hcon->dst);
1908 bacpy(&rpa, BDADDR_ANY);
1910 smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr,
1911 smp->id_addr_type, smp->irk, &rpa);
1914 if (!(smp->remote_key_dist & KEY_DIST_MASK))
1915 smp_distribute_keys(smp);
1920 static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb)
1922 struct smp_cmd_sign_info *rp = (void *) skb->data;
1923 struct l2cap_chan *chan = conn->smp;
1924 struct smp_chan *smp = chan->data;
1925 struct smp_csrk *csrk;
1927 BT_DBG("conn %p", conn);
1929 if (skb->len < sizeof(*rp))
1930 return SMP_INVALID_PARAMS;
1932 /* Mark the information as received */
1933 smp->remote_key_dist &= ~SMP_DIST_SIGN;
1935 skb_pull(skb, sizeof(*rp));
1937 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
1939 csrk->master = 0x01;
1940 memcpy(csrk->val, rp->csrk, sizeof(csrk->val));
1943 smp_distribute_keys(smp);
1948 static u8 sc_select_method(struct smp_chan *smp)
1950 struct l2cap_conn *conn = smp->conn;
1951 struct hci_conn *hcon = conn->hcon;
1952 struct smp_cmd_pairing *local, *remote;
1953 u8 local_mitm, remote_mitm, local_io, remote_io, method;
1955 /* The preq/prsp contain the raw Pairing Request/Response PDUs
1956 * which are needed as inputs to some crypto functions. To get
1957 * the "struct smp_cmd_pairing" from them we need to skip the
1958 * first byte which contains the opcode.
1961 local = (void *) &smp->preq[1];
1962 remote = (void *) &smp->prsp[1];
1964 local = (void *) &smp->prsp[1];
1965 remote = (void *) &smp->preq[1];
1968 local_io = local->io_capability;
1969 remote_io = remote->io_capability;
1971 local_mitm = (local->auth_req & SMP_AUTH_MITM);
1972 remote_mitm = (remote->auth_req & SMP_AUTH_MITM);
1974 /* If either side wants MITM, look up the method from the table,
1975 * otherwise use JUST WORKS.
1977 if (local_mitm || remote_mitm)
1978 method = get_auth_method(smp, local_io, remote_io);
1980 method = JUST_WORKS;
1982 /* Don't confirm locally initiated pairing attempts */
1983 if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags))
1984 method = JUST_WORKS;
1989 static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb)
1991 struct smp_cmd_public_key *key = (void *) skb->data;
1992 struct hci_conn *hcon = conn->hcon;
1993 struct l2cap_chan *chan = conn->smp;
1994 struct smp_chan *smp = chan->data;
1995 struct hci_dev *hdev = hcon->hdev;
1996 struct smp_cmd_pairing_confirm cfm;
1999 BT_DBG("conn %p", conn);
2001 if (skb->len < sizeof(*key))
2002 return SMP_INVALID_PARAMS;
2004 memcpy(smp->remote_pk, key, 64);
2006 /* Non-initiating device sends its public key after receiving
2007 * the key from the initiating device.
2010 err = sc_send_public_key(smp);
2015 BT_DBG("Remote Public Key X: %32phN", smp->remote_pk);
2016 BT_DBG("Remote Public Key Y: %32phN", &smp->remote_pk[32]);
2018 if (!ecdh_shared_secret(smp->remote_pk, smp->local_sk, smp->dhkey))
2019 return SMP_UNSPECIFIED;
2021 BT_DBG("DHKey %32phN", smp->dhkey);
2023 set_bit(SMP_FLAG_REMOTE_PK, &smp->flags);
2025 smp->method = sc_select_method(smp);
2027 BT_DBG("%s selected method 0x%02x", hdev->name, smp->method);
2029 /* JUST_WORKS and JUST_CFM result in an unauthenticated key */
2030 if (smp->method == JUST_WORKS || smp->method == JUST_CFM)
2031 hcon->pending_sec_level = BT_SECURITY_MEDIUM;
2033 hcon->pending_sec_level = BT_SECURITY_FIPS;
2035 if (!memcmp(debug_pk, smp->remote_pk, 64))
2036 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
2038 /* The Initiating device waits for the non-initiating device to
2039 * send the confirm value.
2041 if (conn->hcon->out)
2044 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd,
2045 0, cfm.confirm_val);
2047 return SMP_UNSPECIFIED;
2049 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
2050 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2055 static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb)
2057 struct smp_cmd_dhkey_check *check = (void *) skb->data;
2058 struct l2cap_chan *chan = conn->smp;
2059 struct hci_conn *hcon = conn->hcon;
2060 struct smp_chan *smp = chan->data;
2061 u8 a[7], b[7], *local_addr, *remote_addr;
2062 u8 io_cap[3], r[16], e[16];
2066 BT_DBG("conn %p", conn);
2068 if (skb->len < sizeof(*check))
2069 return SMP_INVALID_PARAMS;
2071 memcpy(a, &hcon->init_addr, 6);
2072 memcpy(b, &hcon->resp_addr, 6);
2073 a[6] = hcon->init_addr_type;
2074 b[6] = hcon->resp_addr_type;
2079 memcpy(io_cap, &smp->prsp[1], 3);
2083 memcpy(io_cap, &smp->preq[1], 3);
2086 memset(r, 0, sizeof(r));
2088 err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r,
2089 io_cap, remote_addr, local_addr, e);
2091 return SMP_UNSPECIFIED;
2093 if (memcmp(check->e, e, 16))
2094 return SMP_DHKEY_CHECK_FAILED;
2096 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
2097 key_type = SMP_LTK_P256_DEBUG;
2099 key_type = SMP_LTK_P256;
2101 if (hcon->pending_sec_level == BT_SECURITY_FIPS)
2106 smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
2107 key_type, auth, smp->tk, smp->enc_key_size,
2111 hci_le_start_enc(hcon, 0, 0, smp->tk);
2112 hcon->enc_key_size = smp->enc_key_size;
2118 static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb)
2120 struct l2cap_conn *conn = chan->conn;
2121 struct hci_conn *hcon = conn->hcon;
2122 struct smp_chan *smp;
2126 if (hcon->type != LE_LINK) {
2134 if (!test_bit(HCI_LE_ENABLED, &hcon->hdev->dev_flags)) {
2135 reason = SMP_PAIRING_NOTSUPP;
2139 code = skb->data[0];
2140 skb_pull(skb, sizeof(code));
2144 if (code > SMP_CMD_MAX)
2147 if (smp && !test_and_clear_bit(code, &smp->allow_cmd))
2150 /* If we don't have a context the only allowed commands are
2151 * pairing request and security request.
2153 if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ)
2157 case SMP_CMD_PAIRING_REQ:
2158 reason = smp_cmd_pairing_req(conn, skb);
2161 case SMP_CMD_PAIRING_FAIL:
2162 smp_failure(conn, 0);
2166 case SMP_CMD_PAIRING_RSP:
2167 reason = smp_cmd_pairing_rsp(conn, skb);
2170 case SMP_CMD_SECURITY_REQ:
2171 reason = smp_cmd_security_req(conn, skb);
2174 case SMP_CMD_PAIRING_CONFIRM:
2175 reason = smp_cmd_pairing_confirm(conn, skb);
2178 case SMP_CMD_PAIRING_RANDOM:
2179 reason = smp_cmd_pairing_random(conn, skb);
2182 case SMP_CMD_ENCRYPT_INFO:
2183 reason = smp_cmd_encrypt_info(conn, skb);
2186 case SMP_CMD_MASTER_IDENT:
2187 reason = smp_cmd_master_ident(conn, skb);
2190 case SMP_CMD_IDENT_INFO:
2191 reason = smp_cmd_ident_info(conn, skb);
2194 case SMP_CMD_IDENT_ADDR_INFO:
2195 reason = smp_cmd_ident_addr_info(conn, skb);
2198 case SMP_CMD_SIGN_INFO:
2199 reason = smp_cmd_sign_info(conn, skb);
2202 case SMP_CMD_PUBLIC_KEY:
2203 reason = smp_cmd_public_key(conn, skb);
2206 case SMP_CMD_DHKEY_CHECK:
2207 reason = smp_cmd_dhkey_check(conn, skb);
2211 BT_DBG("Unknown command code 0x%2.2x", code);
2212 reason = SMP_CMD_NOTSUPP;
2219 smp_failure(conn, reason);
2226 BT_ERR("%s unexpected SMP command 0x%02x from %pMR", hcon->hdev->name,
2232 static void smp_teardown_cb(struct l2cap_chan *chan, int err)
2234 struct l2cap_conn *conn = chan->conn;
2236 BT_DBG("chan %p", chan);
2239 smp_chan_destroy(conn);
2242 l2cap_chan_put(chan);
2245 static void smp_resume_cb(struct l2cap_chan *chan)
2247 struct smp_chan *smp = chan->data;
2248 struct l2cap_conn *conn = chan->conn;
2249 struct hci_conn *hcon = conn->hcon;
2251 BT_DBG("chan %p", chan);
2256 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
2259 cancel_delayed_work(&smp->security_timer);
2261 smp_distribute_keys(smp);
2264 static void smp_ready_cb(struct l2cap_chan *chan)
2266 struct l2cap_conn *conn = chan->conn;
2268 BT_DBG("chan %p", chan);
2271 l2cap_chan_hold(chan);
2274 static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
2278 BT_DBG("chan %p", chan);
2280 err = smp_sig_channel(chan, skb);
2282 struct smp_chan *smp = chan->data;
2285 cancel_delayed_work_sync(&smp->security_timer);
2287 hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE);
2293 static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan,
2294 unsigned long hdr_len,
2295 unsigned long len, int nb)
2297 struct sk_buff *skb;
2299 skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL);
2301 return ERR_PTR(-ENOMEM);
2303 skb->priority = HCI_PRIO_MAX;
2304 bt_cb(skb)->chan = chan;
2309 static const struct l2cap_ops smp_chan_ops = {
2310 .name = "Security Manager",
2311 .ready = smp_ready_cb,
2312 .recv = smp_recv_cb,
2313 .alloc_skb = smp_alloc_skb_cb,
2314 .teardown = smp_teardown_cb,
2315 .resume = smp_resume_cb,
2317 .new_connection = l2cap_chan_no_new_connection,
2318 .state_change = l2cap_chan_no_state_change,
2319 .close = l2cap_chan_no_close,
2320 .defer = l2cap_chan_no_defer,
2321 .suspend = l2cap_chan_no_suspend,
2322 .set_shutdown = l2cap_chan_no_set_shutdown,
2323 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
2324 .memcpy_fromiovec = l2cap_chan_no_memcpy_fromiovec,
2327 static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan)
2329 struct l2cap_chan *chan;
2331 BT_DBG("pchan %p", pchan);
2333 chan = l2cap_chan_create();
2337 chan->chan_type = pchan->chan_type;
2338 chan->ops = &smp_chan_ops;
2339 chan->scid = pchan->scid;
2340 chan->dcid = chan->scid;
2341 chan->imtu = pchan->imtu;
2342 chan->omtu = pchan->omtu;
2343 chan->mode = pchan->mode;
2345 /* Other L2CAP channels may request SMP routines in order to
2346 * change the security level. This means that the SMP channel
2347 * lock must be considered in its own category to avoid lockdep
2350 atomic_set(&chan->nesting, L2CAP_NESTING_SMP);
2352 BT_DBG("created chan %p", chan);
2357 static const struct l2cap_ops smp_root_chan_ops = {
2358 .name = "Security Manager Root",
2359 .new_connection = smp_new_conn_cb,
2361 /* None of these are implemented for the root channel */
2362 .close = l2cap_chan_no_close,
2363 .alloc_skb = l2cap_chan_no_alloc_skb,
2364 .recv = l2cap_chan_no_recv,
2365 .state_change = l2cap_chan_no_state_change,
2366 .teardown = l2cap_chan_no_teardown,
2367 .ready = l2cap_chan_no_ready,
2368 .defer = l2cap_chan_no_defer,
2369 .suspend = l2cap_chan_no_suspend,
2370 .resume = l2cap_chan_no_resume,
2371 .set_shutdown = l2cap_chan_no_set_shutdown,
2372 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
2373 .memcpy_fromiovec = l2cap_chan_no_memcpy_fromiovec,
2376 int smp_register(struct hci_dev *hdev)
2378 struct l2cap_chan *chan;
2379 struct crypto_blkcipher *tfm_aes;
2381 BT_DBG("%s", hdev->name);
2383 tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, 0);
2384 if (IS_ERR(tfm_aes)) {
2385 int err = PTR_ERR(tfm_aes);
2386 BT_ERR("Unable to create crypto context");
2390 chan = l2cap_chan_create();
2392 crypto_free_blkcipher(tfm_aes);
2396 chan->data = tfm_aes;
2398 l2cap_add_scid(chan, L2CAP_CID_SMP);
2400 l2cap_chan_set_defaults(chan);
2402 bacpy(&chan->src, &hdev->bdaddr);
2403 chan->src_type = BDADDR_LE_PUBLIC;
2404 chan->state = BT_LISTEN;
2405 chan->mode = L2CAP_MODE_BASIC;
2406 chan->imtu = L2CAP_DEFAULT_MTU;
2407 chan->ops = &smp_root_chan_ops;
2409 /* Set correct nesting level for a parent/listening channel */
2410 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
2412 hdev->smp_data = chan;
2417 void smp_unregister(struct hci_dev *hdev)
2419 struct l2cap_chan *chan = hdev->smp_data;
2420 struct crypto_blkcipher *tfm_aes;
2425 BT_DBG("%s chan %p", hdev->name, chan);
2427 tfm_aes = chan->data;
2430 crypto_free_blkcipher(tfm_aes);
2433 hdev->smp_data = NULL;
2434 l2cap_chan_put(chan);