1/* 2 BlueZ - Bluetooth protocol stack for Linux 3 Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). 4 5 This program is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License version 2 as 7 published by the Free Software Foundation; 8 9 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 10 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 11 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. 12 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY 13 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES 14 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 18 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS, 19 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS 20 SOFTWARE IS DISCLAIMED. 21*/ 22 23#include <linux/debugfs.h> 24#include <linux/scatterlist.h> 25#include <crypto/aes.h> 26#include <crypto/hash.h> 27#include <crypto/kpp.h> 28#include <crypto/utils.h> 29 30#include <net/bluetooth/bluetooth.h> 31#include <net/bluetooth/hci_core.h> 32#include <net/bluetooth/l2cap.h> 33#include <net/bluetooth/mgmt.h> 34 35#include "ecdh_helper.h" 36#include "smp.h" 37 38#define SMP_DEV(hdev) \ 39 ((struct smp_dev *)((struct l2cap_chan *)((hdev)->smp_data))->data) 40 41/* Low-level debug macros to be used for stuff that we don't want 42 * accidentally in dmesg, i.e. the values of the various crypto keys 43 * and the inputs & outputs of crypto functions. 44 */ 45#ifdef DEBUG 46#define SMP_DBG(fmt, ...) printk(KERN_DEBUG "%s: " fmt, __func__, \ 47 ##__VA_ARGS__) 48#else 49#define SMP_DBG(fmt, ...) no_printk(KERN_DEBUG "%s: " fmt, __func__, \ 50 ##__VA_ARGS__) 51#endif 52 53#define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd) 54 55/* Keys which are not distributed with Secure Connections */ 56#define SMP_SC_NO_DIST (SMP_DIST_ENC_KEY | SMP_DIST_LINK_KEY) 57 58#define SMP_TIMEOUT msecs_to_jiffies(30000) 59 60#define ID_ADDR_TIMEOUT msecs_to_jiffies(200) 61 62#define AUTH_REQ_MASK(dev) (hci_dev_test_flag(dev, HCI_SC_ENABLED) ? \ 63 0x3f : 0x07) 64#define KEY_DIST_MASK 0x07 65 66/* Maximum message length that can be passed to aes_cmac */ 67#define CMAC_MSG_MAX 80 68 69enum { 70 SMP_FLAG_TK_VALID, 71 SMP_FLAG_CFM_PENDING, 72 SMP_FLAG_MITM_AUTH, 73 SMP_FLAG_COMPLETE, 74 SMP_FLAG_INITIATOR, 75 SMP_FLAG_SC, 76 SMP_FLAG_REMOTE_PK, 77 SMP_FLAG_DEBUG_KEY, 78 SMP_FLAG_WAIT_USER, 79 SMP_FLAG_DHKEY_PENDING, 80 SMP_FLAG_REMOTE_OOB, 81 SMP_FLAG_LOCAL_OOB, 82 SMP_FLAG_CT2, 83}; 84 85struct smp_dev { 86 /* Secure Connections OOB data */ 87 bool local_oob; 88 u8 local_pk[64]; 89 u8 local_rand[16]; 90 bool debug_key; 91 92 struct crypto_shash *tfm_cmac; 93 struct crypto_kpp *tfm_ecdh; 94}; 95 96struct smp_chan { 97 struct l2cap_conn *conn; 98 struct delayed_work security_timer; 99 unsigned long allow_cmd; /* Bitmask of allowed commands */ 100 101 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 *responder_csrk; 116 struct smp_ltk *ltk; 117 struct smp_ltk *responder_ltk; 118 struct smp_irk *remote_irk; 119 u8 *link_key; 120 unsigned long flags; 121 u8 method; 122 u8 passkey_round; 123 124 /* Secure Connections variables */ 125 u8 local_pk[64]; 126 u8 remote_pk[64]; 127 u8 dhkey[32]; 128 u8 mackey[16]; 129 130 struct crypto_shash *tfm_cmac; 131 struct crypto_kpp *tfm_ecdh; 132}; 133 134/* These debug key values are defined in the SMP section of the core 135 * specification. debug_pk is the public debug key and debug_sk the 136 * private debug key. 137 */ 138static const u8 debug_pk[64] = { 139 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 140 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 141 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 142 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20, 143 144 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74, 145 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76, 146 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63, 147 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc, 148}; 149 150static const u8 debug_sk[32] = { 151 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58, 152 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a, 153 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74, 154 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f, 155}; 156 157static inline void swap_buf(const u8 *src, u8 *dst, size_t len) 158{ 159 size_t i; 160 161 for (i = 0; i < len; i++) 162 dst[len - 1 - i] = src[i]; 163} 164 165/* The following functions map to the LE SC SMP crypto functions 166 * AES-CMAC, f4, f5, f6, g2 and h6. 167 */ 168 169static int aes_cmac(struct crypto_shash *tfm, const u8 k[16], const u8 *m, 170 size_t len, u8 mac[16]) 171{ 172 uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX]; 173 int err; 174 175 if (len > CMAC_MSG_MAX) 176 return -EFBIG; 177 178 if (!tfm) { 179 BT_ERR("tfm %p", tfm); 180 return -EINVAL; 181 } 182 183 /* Swap key and message from LSB to MSB */ 184 swap_buf(k, tmp, 16); 185 swap_buf(m, msg_msb, len); 186 187 SMP_DBG("msg (len %zu) %*phN", len, (int) len, m); 188 SMP_DBG("key %16phN", k); 189 190 err = crypto_shash_setkey(tfm, tmp, 16); 191 if (err) { 192 BT_ERR("cipher setkey failed: %d", err); 193 return err; 194 } 195 196 err = crypto_shash_tfm_digest(tfm, msg_msb, len, mac_msb); 197 if (err) { 198 BT_ERR("Hash computation error %d", err); 199 return err; 200 } 201 202 swap_buf(mac_msb, mac, 16); 203 204 SMP_DBG("mac %16phN", mac); 205 206 return 0; 207} 208 209static int smp_f4(struct crypto_shash *tfm_cmac, const u8 u[32], 210 const u8 v[32], const u8 x[16], u8 z, u8 res[16]) 211{ 212 u8 m[65]; 213 int err; 214 215 SMP_DBG("u %32phN", u); 216 SMP_DBG("v %32phN", v); 217 SMP_DBG("x %16phN z %02x", x, z); 218 219 m[0] = z; 220 memcpy(m + 1, v, 32); 221 memcpy(m + 33, u, 32); 222 223 err = aes_cmac(tfm_cmac, x, m, sizeof(m), res); 224 if (err) 225 return err; 226 227 SMP_DBG("res %16phN", res); 228 229 return err; 230} 231 232static int smp_f5(struct crypto_shash *tfm_cmac, const u8 w[32], 233 const u8 n1[16], const u8 n2[16], const u8 a1[7], 234 const u8 a2[7], u8 mackey[16], u8 ltk[16]) 235{ 236 /* The btle, salt and length "magic" values are as defined in 237 * the SMP section of the Bluetooth core specification. In ASCII 238 * the btle value ends up being 'btle'. The salt is just a 239 * random number whereas length is the value 256 in little 240 * endian format. 241 */ 242 const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 }; 243 const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60, 244 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c }; 245 const u8 length[2] = { 0x00, 0x01 }; 246 u8 m[53], t[16]; 247 int err; 248 249 SMP_DBG("w %32phN", w); 250 SMP_DBG("n1 %16phN n2 %16phN", n1, n2); 251 SMP_DBG("a1 %7phN a2 %7phN", a1, a2); 252 253 err = aes_cmac(tfm_cmac, salt, w, 32, t); 254 if (err) 255 return err; 256 257 SMP_DBG("t %16phN", t); 258 259 memcpy(m, length, 2); 260 memcpy(m + 2, a2, 7); 261 memcpy(m + 9, a1, 7); 262 memcpy(m + 16, n2, 16); 263 memcpy(m + 32, n1, 16); 264 memcpy(m + 48, btle, 4); 265 266 m[52] = 0; /* Counter */ 267 268 err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey); 269 if (err) 270 return err; 271 272 SMP_DBG("mackey %16phN", mackey); 273 274 m[52] = 1; /* Counter */ 275 276 err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk); 277 if (err) 278 return err; 279 280 SMP_DBG("ltk %16phN", ltk); 281 282 return 0; 283} 284 285static int smp_f6(struct crypto_shash *tfm_cmac, const u8 w[16], 286 const u8 n1[16], const u8 n2[16], const u8 r[16], 287 const u8 io_cap[3], const u8 a1[7], const u8 a2[7], 288 u8 res[16]) 289{ 290 u8 m[65]; 291 int err; 292 293 SMP_DBG("w %16phN", w); 294 SMP_DBG("n1 %16phN n2 %16phN", n1, n2); 295 SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2); 296 297 memcpy(m, a2, 7); 298 memcpy(m + 7, a1, 7); 299 memcpy(m + 14, io_cap, 3); 300 memcpy(m + 17, r, 16); 301 memcpy(m + 33, n2, 16); 302 memcpy(m + 49, n1, 16); 303 304 err = aes_cmac(tfm_cmac, w, m, sizeof(m), res); 305 if (err) 306 return err; 307 308 SMP_DBG("res %16phN", res); 309 310 return err; 311} 312 313static int smp_g2(struct crypto_shash *tfm_cmac, const u8 u[32], const u8 v[32], 314 const u8 x[16], const u8 y[16], u32 *val) 315{ 316 u8 m[80], tmp[16]; 317 int err; 318 319 SMP_DBG("u %32phN", u); 320 SMP_DBG("v %32phN", v); 321 SMP_DBG("x %16phN y %16phN", x, y); 322 323 memcpy(m, y, 16); 324 memcpy(m + 16, v, 32); 325 memcpy(m + 48, u, 32); 326 327 err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp); 328 if (err) 329 return err; 330 331 *val = get_unaligned_le32(tmp); 332 *val %= 1000000; 333 334 SMP_DBG("val %06u", *val); 335 336 return 0; 337} 338 339static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16], 340 const u8 key_id[4], u8 res[16]) 341{ 342 int err; 343 344 SMP_DBG("w %16phN key_id %4phN", w, key_id); 345 346 err = aes_cmac(tfm_cmac, w, key_id, 4, res); 347 if (err) 348 return err; 349 350 SMP_DBG("res %16phN", res); 351 352 return err; 353} 354 355static int smp_h7(struct crypto_shash *tfm_cmac, const u8 w[16], 356 const u8 salt[16], u8 res[16]) 357{ 358 int err; 359 360 SMP_DBG("w %16phN salt %16phN", w, salt); 361 362 err = aes_cmac(tfm_cmac, salt, w, 16, res); 363 if (err) 364 return err; 365 366 SMP_DBG("res %16phN", res); 367 368 return err; 369} 370 371/* The following functions map to the legacy SMP crypto functions e, c1, 372 * s1 and ah. 373 */ 374 375static int smp_e(const u8 *k, u8 *r) 376{ 377 struct crypto_aes_ctx ctx; 378 uint8_t tmp[16], data[16]; 379 int err; 380 381 SMP_DBG("k %16phN r %16phN", k, r); 382 383 /* The most significant octet of key corresponds to k[0] */ 384 swap_buf(k, tmp, 16); 385 386 err = aes_expandkey(&ctx, tmp, 16); 387 if (err) { 388 BT_ERR("cipher setkey failed: %d", err); 389 return err; 390 } 391 392 /* Most significant octet of plaintextData corresponds to data[0] */ 393 swap_buf(r, data, 16); 394 395 aes_encrypt(&ctx, data, data); 396 397 /* Most significant octet of encryptedData corresponds to data[0] */ 398 swap_buf(data, r, 16); 399 400 SMP_DBG("r %16phN", r); 401 402 memzero_explicit(&ctx, sizeof(ctx)); 403 return err; 404} 405 406static int smp_c1(const u8 k[16], 407 const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat, 408 const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16]) 409{ 410 u8 p1[16], p2[16]; 411 int err; 412 413 SMP_DBG("k %16phN r %16phN", k, r); 414 SMP_DBG("iat %u ia %6phN rat %u ra %6phN", _iat, ia, _rat, ra); 415 SMP_DBG("preq %7phN pres %7phN", preq, pres); 416 417 memset(p1, 0, 16); 418 419 /* p1 = pres || preq || _rat || _iat */ 420 p1[0] = _iat; 421 p1[1] = _rat; 422 memcpy(p1 + 2, preq, 7); 423 memcpy(p1 + 9, pres, 7); 424 425 SMP_DBG("p1 %16phN", p1); 426 427 /* res = r XOR p1 */ 428 crypto_xor_cpy(res, r, p1, sizeof(p1)); 429 430 /* res = e(k, res) */ 431 err = smp_e(k, res); 432 if (err) { 433 BT_ERR("Encrypt data error"); 434 return err; 435 } 436 437 /* p2 = padding || ia || ra */ 438 memcpy(p2, ra, 6); 439 memcpy(p2 + 6, ia, 6); 440 memset(p2 + 12, 0, 4); 441 442 SMP_DBG("p2 %16phN", p2); 443 444 /* res = res XOR p2 */ 445 crypto_xor(res, p2, sizeof(p2)); 446 447 /* res = e(k, res) */ 448 err = smp_e(k, res); 449 if (err) 450 BT_ERR("Encrypt data error"); 451 452 return err; 453} 454 455static int smp_s1(const u8 k[16], 456 const u8 r1[16], const u8 r2[16], u8 _r[16]) 457{ 458 int err; 459 460 /* Just least significant octets from r1 and r2 are considered */ 461 memcpy(_r, r2, 8); 462 memcpy(_r + 8, r1, 8); 463 464 err = smp_e(k, _r); 465 if (err) 466 BT_ERR("Encrypt data error"); 467 468 return err; 469} 470 471static int smp_ah(const u8 irk[16], const u8 r[3], u8 res[3]) 472{ 473 u8 _res[16]; 474 int err; 475 476 /* r' = padding || r */ 477 memcpy(_res, r, 3); 478 memset(_res + 3, 0, 13); 479 480 err = smp_e(irk, _res); 481 if (err) { 482 BT_ERR("Encrypt error"); 483 return err; 484 } 485 486 /* The output of the random address function ah is: 487 * ah(k, r) = e(k, r') mod 2^24 488 * The output of the security function e is then truncated to 24 bits 489 * by taking the least significant 24 bits of the output of e as the 490 * result of ah. 491 */ 492 memcpy(res, _res, 3); 493 494 return 0; 495} 496 497bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16], 498 const bdaddr_t *bdaddr) 499{ 500 struct l2cap_chan *chan = hdev->smp_data; 501 u8 hash[3]; 502 int err; 503 504 if (!chan || !chan->data) 505 return false; 506 507 bt_dev_dbg(hdev, "RPA %pMR IRK %*phN", bdaddr, 16, irk); 508 509 err = smp_ah(irk, &bdaddr->b[3], hash); 510 if (err) 511 return false; 512 513 return !crypto_memneq(bdaddr->b, hash, 3); 514} 515 516int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa) 517{ 518 struct l2cap_chan *chan = hdev->smp_data; 519 int err; 520 521 if (!chan || !chan->data) 522 return -EOPNOTSUPP; 523 524 get_random_bytes(&rpa->b[3], 3); 525 526 rpa->b[5] &= 0x3f; /* Clear two most significant bits */ 527 rpa->b[5] |= 0x40; /* Set second most significant bit */ 528 529 err = smp_ah(irk, &rpa->b[3], rpa->b); 530 if (err < 0) 531 return err; 532 533 bt_dev_dbg(hdev, "RPA %pMR", rpa); 534 535 return 0; 536} 537 538int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16]) 539{ 540 struct l2cap_chan *chan = hdev->smp_data; 541 struct smp_dev *smp; 542 int err; 543 544 if (!chan || !chan->data) 545 return -EOPNOTSUPP; 546 547 smp = chan->data; 548 549 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) { 550 bt_dev_dbg(hdev, "Using debug keys"); 551 err = set_ecdh_privkey(smp->tfm_ecdh, debug_sk); 552 if (err) 553 return err; 554 memcpy(smp->local_pk, debug_pk, 64); 555 smp->debug_key = true; 556 } else { 557 while (true) { 558 /* Generate key pair for Secure Connections */ 559 err = generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk); 560 if (err) 561 return err; 562 563 /* This is unlikely, but we need to check that 564 * we didn't accidentally generate a debug key. 565 */ 566 if (crypto_memneq(smp->local_pk, debug_pk, 64)) 567 break; 568 } 569 smp->debug_key = false; 570 } 571 572 SMP_DBG("OOB Public Key X: %32phN", smp->local_pk); 573 SMP_DBG("OOB Public Key Y: %32phN", smp->local_pk + 32); 574 575 get_random_bytes(smp->local_rand, 16); 576 577 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->local_pk, 578 smp->local_rand, 0, hash); 579 if (err < 0) 580 return err; 581 582 memcpy(rand, smp->local_rand, 16); 583 584 smp->local_oob = true; 585 586 return 0; 587} 588 589static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data) 590{ 591 struct l2cap_chan *chan = conn->smp; 592 struct smp_chan *smp; 593 struct kvec iv[2]; 594 struct msghdr msg; 595 596 if (!chan) 597 return; 598 599 bt_dev_dbg(conn->hcon->hdev, "code 0x%2.2x", code); 600 601 iv[0].iov_base = &code; 602 iv[0].iov_len = 1; 603 604 iv[1].iov_base = data; 605 iv[1].iov_len = len; 606 607 memset(&msg, 0, sizeof(msg)); 608 609 iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, iv, 2, 1 + len); 610 611 l2cap_chan_send(chan, &msg, 1 + len); 612 613 if (!chan->data) 614 return; 615 616 smp = chan->data; 617 618 cancel_delayed_work_sync(&smp->security_timer); 619 schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT); 620} 621 622static u8 authreq_to_seclevel(u8 authreq) 623{ 624 if (authreq & SMP_AUTH_MITM) { 625 if (authreq & SMP_AUTH_SC) 626 return BT_SECURITY_FIPS; 627 else 628 return BT_SECURITY_HIGH; 629 } else { 630 return BT_SECURITY_MEDIUM; 631 } 632} 633 634static __u8 seclevel_to_authreq(__u8 sec_level) 635{ 636 switch (sec_level) { 637 case BT_SECURITY_FIPS: 638 case BT_SECURITY_HIGH: 639 return SMP_AUTH_MITM | SMP_AUTH_BONDING; 640 case BT_SECURITY_MEDIUM: 641 return SMP_AUTH_BONDING; 642 default: 643 return SMP_AUTH_NONE; 644 } 645} 646 647static void build_pairing_cmd(struct l2cap_conn *conn, 648 struct smp_cmd_pairing *req, 649 struct smp_cmd_pairing *rsp, __u8 authreq) 650{ 651 struct l2cap_chan *chan = conn->smp; 652 struct smp_chan *smp = chan->data; 653 struct hci_conn *hcon = conn->hcon; 654 struct hci_dev *hdev = hcon->hdev; 655 u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT; 656 657 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) { 658 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 659 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 660 authreq |= SMP_AUTH_BONDING; 661 } else { 662 authreq &= ~SMP_AUTH_BONDING; 663 } 664 665 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING)) 666 remote_dist |= SMP_DIST_ID_KEY; 667 668 if (hci_dev_test_flag(hdev, HCI_PRIVACY)) 669 local_dist |= SMP_DIST_ID_KEY; 670 671 if (hci_dev_test_flag(hdev, HCI_SC_ENABLED) && 672 (authreq & SMP_AUTH_SC)) { 673 struct oob_data *oob_data; 674 u8 bdaddr_type; 675 676 if (hci_dev_test_flag(hdev, HCI_SSP_ENABLED)) { 677 local_dist |= SMP_DIST_LINK_KEY; 678 remote_dist |= SMP_DIST_LINK_KEY; 679 } 680 681 if (hcon->dst_type == ADDR_LE_DEV_PUBLIC) 682 bdaddr_type = BDADDR_LE_PUBLIC; 683 else 684 bdaddr_type = BDADDR_LE_RANDOM; 685 686 oob_data = hci_find_remote_oob_data(hdev, &hcon->dst, 687 bdaddr_type); 688 if (oob_data && oob_data->present) { 689 set_bit(SMP_FLAG_REMOTE_OOB, &smp->flags); 690 oob_flag = SMP_OOB_PRESENT; 691 memcpy(smp->rr, oob_data->rand256, 16); 692 memcpy(smp->pcnf, oob_data->hash256, 16); 693 SMP_DBG("OOB Remote Confirmation: %16phN", smp->pcnf); 694 SMP_DBG("OOB Remote Random: %16phN", smp->rr); 695 } 696 697 } else { 698 authreq &= ~SMP_AUTH_SC; 699 } 700 701 if (rsp == NULL) { 702 req->io_capability = conn->hcon->io_capability; 703 req->oob_flag = oob_flag; 704 req->max_key_size = hdev->le_max_key_size; 705 req->init_key_dist = local_dist; 706 req->resp_key_dist = remote_dist; 707 req->auth_req = (authreq & AUTH_REQ_MASK(hdev)); 708 709 smp->remote_key_dist = remote_dist; 710 return; 711 } 712 713 rsp->io_capability = conn->hcon->io_capability; 714 rsp->oob_flag = oob_flag; 715 rsp->max_key_size = hdev->le_max_key_size; 716 rsp->init_key_dist = req->init_key_dist & remote_dist; 717 rsp->resp_key_dist = req->resp_key_dist & local_dist; 718 rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev)); 719 720 smp->remote_key_dist = rsp->init_key_dist; 721} 722 723static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size) 724{ 725 struct l2cap_chan *chan = conn->smp; 726 struct hci_dev *hdev = conn->hcon->hdev; 727 struct smp_chan *smp = chan->data; 728 729 if (conn->hcon->pending_sec_level == BT_SECURITY_FIPS && 730 max_key_size != SMP_MAX_ENC_KEY_SIZE) 731 return SMP_ENC_KEY_SIZE; 732 733 if (max_key_size > hdev->le_max_key_size || 734 max_key_size < SMP_MIN_ENC_KEY_SIZE) 735 return SMP_ENC_KEY_SIZE; 736 737 smp->enc_key_size = max_key_size; 738 739 return 0; 740} 741 742static void smp_chan_destroy(struct l2cap_conn *conn) 743{ 744 struct l2cap_chan *chan = conn->smp; 745 struct smp_chan *smp = chan->data; 746 struct hci_conn *hcon = conn->hcon; 747 bool complete; 748 749 BUG_ON(!smp); 750 751 cancel_delayed_work_sync(&smp->security_timer); 752 753 complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags); 754 mgmt_smp_complete(hcon, complete); 755 756 kfree_sensitive(smp->csrk); 757 kfree_sensitive(smp->responder_csrk); 758 kfree_sensitive(smp->link_key); 759 760 crypto_free_shash(smp->tfm_cmac); 761 crypto_free_kpp(smp->tfm_ecdh); 762 763 /* Ensure that we don't leave any debug key around if debug key 764 * support hasn't been explicitly enabled. 765 */ 766 if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG && 767 !hci_dev_test_flag(hcon->hdev, HCI_KEEP_DEBUG_KEYS)) { 768 list_del_rcu(&smp->ltk->list); 769 kfree_rcu(smp->ltk, rcu); 770 smp->ltk = NULL; 771 } 772 773 /* If pairing failed clean up any keys we might have */ 774 if (!complete) { 775 if (smp->ltk) { 776 list_del_rcu(&smp->ltk->list); 777 kfree_rcu(smp->ltk, rcu); 778 } 779 780 if (smp->responder_ltk) { 781 list_del_rcu(&smp->responder_ltk->list); 782 kfree_rcu(smp->responder_ltk, rcu); 783 } 784 785 if (smp->remote_irk) { 786 list_del_rcu(&smp->remote_irk->list); 787 kfree_rcu(smp->remote_irk, rcu); 788 } 789 } 790 791 chan->data = NULL; 792 kfree_sensitive(smp); 793 hci_conn_drop(hcon); 794} 795 796static void smp_failure(struct l2cap_conn *conn, u8 reason) 797{ 798 struct hci_conn *hcon = conn->hcon; 799 struct l2cap_chan *chan = conn->smp; 800 801 if (reason) 802 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), 803 &reason); 804 805 mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE); 806 807 if (chan->data) 808 smp_chan_destroy(conn); 809} 810 811#define JUST_WORKS 0x00 812#define JUST_CFM 0x01 813#define REQ_PASSKEY 0x02 814#define CFM_PASSKEY 0x03 815#define REQ_OOB 0x04 816#define DSP_PASSKEY 0x05 817#define OVERLAP 0xFF 818 819static const u8 gen_method[5][5] = { 820 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 821 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 822 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 823 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM }, 824 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP }, 825}; 826 827static const u8 sc_method[5][5] = { 828 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 829 { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 830 { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY }, 831 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM }, 832 { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 833}; 834 835static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io) 836{ 837 /* If either side has unknown io_caps, use JUST_CFM (which gets 838 * converted later to JUST_WORKS if we're initiators. 839 */ 840 if (local_io > SMP_IO_KEYBOARD_DISPLAY || 841 remote_io > SMP_IO_KEYBOARD_DISPLAY) 842 return JUST_CFM; 843 844 if (test_bit(SMP_FLAG_SC, &smp->flags)) 845 return sc_method[remote_io][local_io]; 846 847 return gen_method[remote_io][local_io]; 848} 849 850static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth, 851 u8 local_io, u8 remote_io) 852{ 853 struct hci_conn *hcon = conn->hcon; 854 struct l2cap_chan *chan = conn->smp; 855 struct smp_chan *smp = chan->data; 856 u32 passkey = 0; 857 int ret; 858 859 /* Initialize key for JUST WORKS */ 860 memset(smp->tk, 0, sizeof(smp->tk)); 861 clear_bit(SMP_FLAG_TK_VALID, &smp->flags); 862 863 bt_dev_dbg(hcon->hdev, "auth:%u lcl:%u rem:%u", auth, local_io, 864 remote_io); 865 866 /* If neither side wants MITM, either "just" confirm an incoming 867 * request or use just-works for outgoing ones. The JUST_CFM 868 * will be converted to JUST_WORKS if necessary later in this 869 * function. If either side has MITM look up the method from the 870 * table. 871 */ 872 if (!(auth & SMP_AUTH_MITM)) 873 smp->method = JUST_CFM; 874 else 875 smp->method = get_auth_method(smp, local_io, remote_io); 876 877 /* Don't confirm locally initiated pairing attempts */ 878 if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, 879 &smp->flags)) 880 smp->method = JUST_WORKS; 881 882 /* Don't bother user space with no IO capabilities */ 883 if (smp->method == JUST_CFM && 884 hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 885 smp->method = JUST_WORKS; 886 887 /* If Just Works, Continue with Zero TK and ask user-space for 888 * confirmation */ 889 if (smp->method == JUST_WORKS) { 890 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, 891 hcon->type, 892 hcon->dst_type, 893 passkey, 1); 894 if (ret) 895 return ret; 896 set_bit(SMP_FLAG_WAIT_USER, &smp->flags); 897 return 0; 898 } 899 900 /* If this function is used for SC -> legacy fallback we 901 * can only recover the just-works case. 902 */ 903 if (test_bit(SMP_FLAG_SC, &smp->flags)) 904 return -EINVAL; 905 906 /* 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; 911 } 912 913 /* If both devices have Keyboard-Display I/O, the initiator 914 * Confirms and the responder Enters the passkey. 915 */ 916 if (smp->method == OVERLAP) { 917 if (hcon->role == HCI_ROLE_MASTER) 918 smp->method = CFM_PASSKEY; 919 else 920 smp->method = REQ_PASSKEY; 921 } 922 923 /* 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_dev_dbg(hcon->hdev, "PassKey: %u", passkey); 930 set_bit(SMP_FLAG_TK_VALID, &smp->flags); 931 } 932 933 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); 944 945 return ret; 946} 947 948static u8 smp_confirm(struct smp_chan *smp) 949{ 950 struct l2cap_conn *conn = smp->conn; 951 struct smp_cmd_pairing_confirm cp; 952 int ret; 953 954 bt_dev_dbg(conn->hcon->hdev, "conn %p", conn); 955 956 ret = smp_c1(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; 962 963 clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 964 965 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp); 966 967 if (conn->hcon->out) 968 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 969 else 970 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 971 972 return 0; 973} 974 975static u8 smp_random(struct smp_chan *smp) 976{ 977 struct l2cap_conn *conn = smp->conn; 978 struct hci_conn *hcon = conn->hcon; 979 u8 confirm[16]; 980 int ret; 981 982 bt_dev_dbg(conn->hcon->hdev, "conn %p %s", conn, 983 conn->hcon->out ? "initiator" : "responder"); 984 985 ret = smp_c1(smp->tk, smp->rrnd, smp->preq, smp->prsp, 986 hcon->init_addr_type, &hcon->init_addr, 987 hcon->resp_addr_type, &hcon->resp_addr, confirm); 988 if (ret) 989 return SMP_UNSPECIFIED; 990 991 if (crypto_memneq(smp->pcnf, confirm, sizeof(smp->pcnf))) { 992 bt_dev_err(hcon->hdev, "pairing failed " 993 "(confirmation values mismatch)"); 994 return SMP_CONFIRM_FAILED; 995 } 996 997 if (hcon->out) { 998 u8 stk[16]; 999 __le64 rand = 0; 1000 __le16 ediv = 0; 1001 1002 smp_s1(smp->tk, smp->rrnd, smp->prnd, stk); 1003 1004 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) 1005 return SMP_UNSPECIFIED; 1006 1007 hci_le_start_enc(hcon, ediv, rand, stk, smp->enc_key_size); 1008 hcon->enc_key_size = smp->enc_key_size; 1009 set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); 1010 } else { 1011 u8 stk[16], auth; 1012 __le64 rand = 0; 1013 __le16 ediv = 0; 1014 1015 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 1016 smp->prnd); 1017 1018 smp_s1(smp->tk, smp->prnd, smp->rrnd, stk); 1019 1020 if (hcon->pending_sec_level == BT_SECURITY_HIGH) 1021 auth = 1; 1022 else 1023 auth = 0; 1024 1025 /* Even though there's no _RESPONDER suffix this is the 1026 * responder STK we're adding for later lookup (the initiator 1027 * STK never needs to be stored). 1028 */ 1029 hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, 1030 SMP_STK, auth, stk, smp->enc_key_size, ediv, rand); 1031 } 1032 1033 return 0; 1034} 1035 1036static void smp_notify_keys(struct l2cap_conn *conn) 1037{ 1038 struct l2cap_chan *chan = conn->smp; 1039 struct smp_chan *smp = chan->data; 1040 struct hci_conn *hcon = conn->hcon; 1041 struct hci_dev *hdev = hcon->hdev; 1042 struct smp_cmd_pairing *req = (void *) &smp->preq[1]; 1043 struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1]; 1044 bool persistent; 1045 1046 if (hcon->type == ACL_LINK) { 1047 if (hcon->key_type == HCI_LK_DEBUG_COMBINATION) 1048 persistent = false; 1049 else 1050 persistent = !test_bit(HCI_CONN_FLUSH_KEY, 1051 &hcon->flags); 1052 } else { 1053 /* The LTKs, IRKs and CSRKs should be persistent only if 1054 * both sides had the bonding bit set in their 1055 * authentication requests. 1056 */ 1057 persistent = !!((req->auth_req & rsp->auth_req) & 1058 SMP_AUTH_BONDING); 1059 } 1060 1061 if (smp->remote_irk) { 1062 smp->remote_irk->link_type = hcon->type; 1063 mgmt_new_irk(hdev, smp->remote_irk, persistent); 1064 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). 1068 */ 1069 if (hcon->type == LE_LINK) { 1070 bacpy(&hcon->dst, &smp->remote_irk->bdaddr); 1071 hcon->dst_type = smp->remote_irk->addr_type; 1072 /* Use a short delay to make sure the new address is 1073 * propagated _before_ the channels. 1074 */ 1075 queue_delayed_work(hdev->workqueue, 1076 &conn->id_addr_timer, 1077 ID_ADDR_TIMEOUT); 1078 } 1079 } 1080 1081 if (smp->csrk) { 1082 smp->csrk->link_type = hcon->type; 1083 smp->csrk->bdaddr_type = hcon->dst_type; 1084 bacpy(&smp->csrk->bdaddr, &hcon->dst); 1085 mgmt_new_csrk(hdev, smp->csrk, persistent); 1086 } 1087 1088 if (smp->responder_csrk) { 1089 smp->responder_csrk->link_type = hcon->type; 1090 smp->responder_csrk->bdaddr_type = hcon->dst_type; 1091 bacpy(&smp->responder_csrk->bdaddr, &hcon->dst); 1092 mgmt_new_csrk(hdev, smp->responder_csrk, persistent); 1093 } 1094 1095 if (smp->ltk) { 1096 smp->ltk->link_type = hcon->type; 1097 smp->ltk->bdaddr_type = hcon->dst_type; 1098 bacpy(&smp->ltk->bdaddr, &hcon->dst); 1099 mgmt_new_ltk(hdev, smp->ltk, persistent); 1100 } 1101 1102 if (smp->responder_ltk) { 1103 smp->responder_ltk->link_type = hcon->type; 1104 smp->responder_ltk->bdaddr_type = hcon->dst_type; 1105 bacpy(&smp->responder_ltk->bdaddr, &hcon->dst); 1106 mgmt_new_ltk(hdev, smp->responder_ltk, persistent); 1107 } 1108 1109 if (smp->link_key) { 1110 struct link_key *key; 1111 u8 type; 1112 1113 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags)) 1114 type = HCI_LK_DEBUG_COMBINATION; 1115 else if (hcon->sec_level == BT_SECURITY_FIPS) 1116 type = HCI_LK_AUTH_COMBINATION_P256; 1117 else 1118 type = HCI_LK_UNAUTH_COMBINATION_P256; 1119 1120 key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst, 1121 smp->link_key, type, 0, &persistent); 1122 if (key) { 1123 key->link_type = hcon->type; 1124 key->bdaddr_type = hcon->dst_type; 1125 mgmt_new_link_key(hdev, key, persistent); 1126 1127 /* Don't keep debug keys around if the relevant 1128 * flag is not set. 1129 */ 1130 if (!hci_dev_test_flag(hdev, HCI_KEEP_DEBUG_KEYS) && 1131 key->type == HCI_LK_DEBUG_COMBINATION) { 1132 list_del_rcu(&key->list); 1133 kfree_rcu(key, rcu); 1134 } 1135 } 1136 } 1137} 1138 1139static void sc_add_ltk(struct smp_chan *smp) 1140{ 1141 struct hci_conn *hcon = smp->conn->hcon; 1142 u8 key_type, auth; 1143 1144 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags)) 1145 key_type = SMP_LTK_P256_DEBUG; 1146 else 1147 key_type = SMP_LTK_P256; 1148 1149 if (hcon->pending_sec_level == BT_SECURITY_FIPS) 1150 auth = 1; 1151 else 1152 auth = 0; 1153 1154 smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, 1155 key_type, auth, smp->tk, smp->enc_key_size, 1156 0, 0); 1157} 1158 1159static void sc_generate_link_key(struct smp_chan *smp) 1160{ 1161 /* From core spec. Spells out in ASCII as 'lebr'. */ 1162 const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c }; 1163 1164 smp->link_key = kzalloc(16, GFP_KERNEL); 1165 if (!smp->link_key) 1166 return; 1167 1168 if (test_bit(SMP_FLAG_CT2, &smp->flags)) { 1169 /* SALT = 0x000000000000000000000000746D7031 */ 1170 const u8 salt[16] = { 0x31, 0x70, 0x6d, 0x74 }; 1171 1172 if (smp_h7(smp->tfm_cmac, smp->tk, salt, smp->link_key)) { 1173 kfree_sensitive(smp->link_key); 1174 smp->link_key = NULL; 1175 return; 1176 } 1177 } else { 1178 /* From core spec. Spells out in ASCII as 'tmp1'. */ 1179 const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 }; 1180 1181 if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) { 1182 kfree_sensitive(smp->link_key); 1183 smp->link_key = NULL; 1184 return; 1185 } 1186 } 1187 1188 if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) { 1189 kfree_sensitive(smp->link_key); 1190 smp->link_key = NULL; 1191 return; 1192 } 1193} 1194 1195static void smp_allow_key_dist(struct smp_chan *smp) 1196{ 1197 /* Allow the first expected phase 3 PDU. The rest of the PDUs 1198 * will be allowed in each PDU handler to ensure we receive 1199 * them in the correct order. 1200 */ 1201 if (smp->remote_key_dist & SMP_DIST_ENC_KEY) 1202 SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO); 1203 else if (smp->remote_key_dist & SMP_DIST_ID_KEY) 1204 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); 1205 else if (smp->remote_key_dist & SMP_DIST_SIGN) 1206 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 1207} 1208 1209static void sc_generate_ltk(struct smp_chan *smp) 1210{ 1211 /* From core spec. Spells out in ASCII as 'brle'. */ 1212 const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 }; 1213 struct hci_conn *hcon = smp->conn->hcon; 1214 struct hci_dev *hdev = hcon->hdev; 1215 struct link_key *key; 1216 1217 key = hci_find_link_key(hdev, &hcon->dst); 1218 if (!key) { 1219 bt_dev_err(hdev, "no Link Key found to generate LTK"); 1220 return; 1221 } 1222 1223 if (key->type == HCI_LK_DEBUG_COMBINATION) 1224 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1225 1226 if (test_bit(SMP_FLAG_CT2, &smp->flags)) { 1227 /* SALT = 0x000000000000000000000000746D7032 */ 1228 const u8 salt[16] = { 0x32, 0x70, 0x6d, 0x74 }; 1229 1230 if (smp_h7(smp->tfm_cmac, key->val, salt, smp->tk)) 1231 return; 1232 } else { 1233 /* From core spec. Spells out in ASCII as 'tmp2'. */ 1234 const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 }; 1235 1236 if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk)) 1237 return; 1238 } 1239 1240 if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk)) 1241 return; 1242 1243 sc_add_ltk(smp); 1244} 1245 1246static void smp_distribute_keys(struct smp_chan *smp) 1247{ 1248 struct smp_cmd_pairing *req, *rsp; 1249 struct l2cap_conn *conn = smp->conn; 1250 struct hci_conn *hcon = conn->hcon; 1251 struct hci_dev *hdev = hcon->hdev; 1252 __u8 *keydist; 1253 1254 bt_dev_dbg(hdev, "conn %p", conn); 1255 1256 rsp = (void *) &smp->prsp[1]; 1257 1258 /* The responder sends its keys first */ 1259 if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) { 1260 smp_allow_key_dist(smp); 1261 return; 1262 } 1263 1264 req = (void *) &smp->preq[1]; 1265 1266 if (hcon->out) { 1267 keydist = &rsp->init_key_dist; 1268 *keydist &= req->init_key_dist; 1269 } else { 1270 keydist = &rsp->resp_key_dist; 1271 *keydist &= req->resp_key_dist; 1272 } 1273 1274 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1275 if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY)) 1276 sc_generate_link_key(smp); 1277 if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY)) 1278 sc_generate_ltk(smp); 1279 1280 /* Clear the keys which are generated but not distributed */ 1281 *keydist &= ~SMP_SC_NO_DIST; 1282 } 1283 1284 bt_dev_dbg(hdev, "keydist 0x%x", *keydist); 1285 1286 if (*keydist & SMP_DIST_ENC_KEY) { 1287 struct smp_cmd_encrypt_info enc; 1288 struct smp_cmd_initiator_ident ident; 1289 struct smp_ltk *ltk; 1290 u8 authenticated; 1291 __le16 ediv; 1292 __le64 rand; 1293 1294 /* Make sure we generate only the significant amount of 1295 * bytes based on the encryption key size, and set the rest 1296 * of the value to zeroes. 1297 */ 1298 get_random_bytes(enc.ltk, smp->enc_key_size); 1299 memset(enc.ltk + smp->enc_key_size, 0, 1300 sizeof(enc.ltk) - smp->enc_key_size); 1301 1302 get_random_bytes(&ediv, sizeof(ediv)); 1303 get_random_bytes(&rand, sizeof(rand)); 1304 1305 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc); 1306 1307 authenticated = hcon->sec_level == BT_SECURITY_HIGH; 1308 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, 1309 SMP_LTK_RESPONDER, authenticated, enc.ltk, 1310 smp->enc_key_size, ediv, rand); 1311 smp->responder_ltk = ltk; 1312 1313 ident.ediv = ediv; 1314 ident.rand = rand; 1315 1316 smp_send_cmd(conn, SMP_CMD_INITIATOR_IDENT, sizeof(ident), 1317 &ident); 1318 1319 *keydist &= ~SMP_DIST_ENC_KEY; 1320 } 1321 1322 if (*keydist & SMP_DIST_ID_KEY) { 1323 struct smp_cmd_ident_addr_info addrinfo; 1324 struct smp_cmd_ident_info idinfo; 1325 1326 memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk)); 1327 1328 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo); 1329 1330 /* The hci_conn contains the local identity address 1331 * after the connection has been established. 1332 * 1333 * This is true even when the connection has been 1334 * established using a resolvable random address. 1335 */ 1336 bacpy(&addrinfo.bdaddr, &hcon->src); 1337 addrinfo.addr_type = hcon->src_type; 1338 1339 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo), 1340 &addrinfo); 1341 1342 *keydist &= ~SMP_DIST_ID_KEY; 1343 } 1344 1345 if (*keydist & SMP_DIST_SIGN) { 1346 struct smp_cmd_sign_info sign; 1347 struct smp_csrk *csrk; 1348 1349 /* Generate a new random key */ 1350 get_random_bytes(sign.csrk, sizeof(sign.csrk)); 1351 1352 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); 1353 if (csrk) { 1354 if (hcon->sec_level > BT_SECURITY_MEDIUM) 1355 csrk->type = MGMT_CSRK_LOCAL_AUTHENTICATED; 1356 else 1357 csrk->type = MGMT_CSRK_LOCAL_UNAUTHENTICATED; 1358 memcpy(csrk->val, sign.csrk, sizeof(csrk->val)); 1359 } 1360 smp->responder_csrk = csrk; 1361 1362 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign); 1363 1364 *keydist &= ~SMP_DIST_SIGN; 1365 } 1366 1367 /* If there are still keys to be received wait for them */ 1368 if (smp->remote_key_dist & KEY_DIST_MASK) { 1369 smp_allow_key_dist(smp); 1370 return; 1371 } 1372 1373 set_bit(SMP_FLAG_COMPLETE, &smp->flags); 1374 smp_notify_keys(conn); 1375 1376 smp_chan_destroy(conn); 1377} 1378 1379static void smp_timeout(struct work_struct *work) 1380{ 1381 struct smp_chan *smp = container_of(work, struct smp_chan, 1382 security_timer.work); 1383 struct l2cap_conn *conn = smp->conn; 1384 1385 bt_dev_dbg(conn->hcon->hdev, "conn %p", conn); 1386 1387 hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM); 1388} 1389 1390static struct smp_chan *smp_chan_create(struct l2cap_conn *conn) 1391{ 1392 struct hci_conn *hcon = conn->hcon; 1393 struct l2cap_chan *chan = conn->smp; 1394 struct smp_chan *smp; 1395 1396 smp = kzalloc(sizeof(*smp), GFP_ATOMIC); 1397 if (!smp) 1398 return NULL; 1399 1400 smp->tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 1401 if (IS_ERR(smp->tfm_cmac)) { 1402 bt_dev_err(hcon->hdev, "Unable to create CMAC crypto context"); 1403 goto zfree_smp; 1404 } 1405 1406 smp->tfm_ecdh = crypto_alloc_kpp("ecdh-nist-p256", 0, 0); 1407 if (IS_ERR(smp->tfm_ecdh)) { 1408 bt_dev_err(hcon->hdev, "Unable to create ECDH crypto context"); 1409 goto free_shash; 1410 } 1411 1412 smp->conn = conn; 1413 chan->data = smp; 1414 1415 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL); 1416 1417 INIT_DELAYED_WORK(&smp->security_timer, smp_timeout); 1418 1419 hci_conn_hold(hcon); 1420 1421 return smp; 1422 1423free_shash: 1424 crypto_free_shash(smp->tfm_cmac); 1425zfree_smp: 1426 kfree_sensitive(smp); 1427 return NULL; 1428} 1429 1430static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16]) 1431{ 1432 struct hci_conn *hcon = smp->conn->hcon; 1433 u8 *na, *nb, a[7], b[7]; 1434 1435 if (hcon->out) { 1436 na = smp->prnd; 1437 nb = smp->rrnd; 1438 } else { 1439 na = smp->rrnd; 1440 nb = smp->prnd; 1441 } 1442 1443 memcpy(a, &hcon->init_addr, 6); 1444 memcpy(b, &hcon->resp_addr, 6); 1445 a[6] = hcon->init_addr_type; 1446 b[6] = hcon->resp_addr_type; 1447 1448 return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk); 1449} 1450 1451static void sc_dhkey_check(struct smp_chan *smp) 1452{ 1453 struct hci_conn *hcon = smp->conn->hcon; 1454 struct smp_cmd_dhkey_check check; 1455 u8 a[7], b[7], *local_addr, *remote_addr; 1456 u8 io_cap[3], r[16]; 1457 1458 memcpy(a, &hcon->init_addr, 6); 1459 memcpy(b, &hcon->resp_addr, 6); 1460 a[6] = hcon->init_addr_type; 1461 b[6] = hcon->resp_addr_type; 1462 1463 if (hcon->out) { 1464 local_addr = a; 1465 remote_addr = b; 1466 memcpy(io_cap, &smp->preq[1], 3); 1467 } else { 1468 local_addr = b; 1469 remote_addr = a; 1470 memcpy(io_cap, &smp->prsp[1], 3); 1471 } 1472 1473 memset(r, 0, sizeof(r)); 1474 1475 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 1476 put_unaligned_le32(hcon->passkey_notify, r); 1477 1478 if (smp->method == REQ_OOB) 1479 memcpy(r, smp->rr, 16); 1480 1481 smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap, 1482 local_addr, remote_addr, check.e); 1483 1484 smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check); 1485} 1486 1487static u8 sc_passkey_send_confirm(struct smp_chan *smp) 1488{ 1489 struct l2cap_conn *conn = smp->conn; 1490 struct hci_conn *hcon = conn->hcon; 1491 struct smp_cmd_pairing_confirm cfm; 1492 u8 r; 1493 1494 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01); 1495 r |= 0x80; 1496 1497 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 1498 1499 if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r, 1500 cfm.confirm_val)) 1501 return SMP_UNSPECIFIED; 1502 1503 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm); 1504 1505 return 0; 1506} 1507 1508static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op) 1509{ 1510 struct l2cap_conn *conn = smp->conn; 1511 struct hci_conn *hcon = conn->hcon; 1512 struct hci_dev *hdev = hcon->hdev; 1513 u8 cfm[16], r; 1514 1515 /* Ignore the PDU if we've already done 20 rounds (0 - 19) */ 1516 if (smp->passkey_round >= 20) 1517 return 0; 1518 1519 switch (smp_op) { 1520 case SMP_CMD_PAIRING_RANDOM: 1521 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01); 1522 r |= 0x80; 1523 1524 if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk, 1525 smp->rrnd, r, cfm)) 1526 return SMP_UNSPECIFIED; 1527 1528 if (crypto_memneq(smp->pcnf, cfm, 16)) 1529 return SMP_CONFIRM_FAILED; 1530 1531 smp->passkey_round++; 1532 1533 if (smp->passkey_round == 20) { 1534 /* Generate MacKey and LTK */ 1535 if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk)) 1536 return SMP_UNSPECIFIED; 1537 } 1538 1539 /* The round is only complete when the initiator 1540 * receives pairing random. 1541 */ 1542 if (!hcon->out) { 1543 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 1544 sizeof(smp->prnd), smp->prnd); 1545 if (smp->passkey_round == 20) 1546 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1547 else 1548 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1549 return 0; 1550 } 1551 1552 /* Start the next round */ 1553 if (smp->passkey_round != 20) 1554 return sc_passkey_round(smp, 0); 1555 1556 /* Passkey rounds are complete - start DHKey Check */ 1557 sc_dhkey_check(smp); 1558 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1559 1560 break; 1561 1562 case SMP_CMD_PAIRING_CONFIRM: 1563 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) { 1564 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 1565 return 0; 1566 } 1567 1568 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 1569 1570 if (hcon->out) { 1571 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 1572 sizeof(smp->prnd), smp->prnd); 1573 return 0; 1574 } 1575 1576 return sc_passkey_send_confirm(smp); 1577 1578 case SMP_CMD_PUBLIC_KEY: 1579 default: 1580 /* Initiating device starts the round */ 1581 if (!hcon->out) 1582 return 0; 1583 1584 bt_dev_dbg(hdev, "Starting passkey round %u", 1585 smp->passkey_round + 1); 1586 1587 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1588 1589 return sc_passkey_send_confirm(smp); 1590 } 1591 1592 return 0; 1593} 1594 1595static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey) 1596{ 1597 struct l2cap_conn *conn = smp->conn; 1598 struct hci_conn *hcon = conn->hcon; 1599 u8 smp_op; 1600 1601 clear_bit(SMP_FLAG_WAIT_USER, &smp->flags); 1602 1603 switch (mgmt_op) { 1604 case MGMT_OP_USER_PASSKEY_NEG_REPLY: 1605 smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED); 1606 return 0; 1607 case MGMT_OP_USER_CONFIRM_NEG_REPLY: 1608 smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED); 1609 return 0; 1610 case MGMT_OP_USER_PASSKEY_REPLY: 1611 hcon->passkey_notify = le32_to_cpu(passkey); 1612 smp->passkey_round = 0; 1613 1614 if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) 1615 smp_op = SMP_CMD_PAIRING_CONFIRM; 1616 else 1617 smp_op = 0; 1618 1619 if (sc_passkey_round(smp, smp_op)) 1620 return -EIO; 1621 1622 return 0; 1623 } 1624 1625 /* Initiator sends DHKey check first */ 1626 if (hcon->out) { 1627 sc_dhkey_check(smp); 1628 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1629 } else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) { 1630 sc_dhkey_check(smp); 1631 sc_add_ltk(smp); 1632 } 1633 1634 return 0; 1635} 1636 1637int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey) 1638{ 1639 struct l2cap_conn *conn = hcon->l2cap_data; 1640 struct l2cap_chan *chan; 1641 struct smp_chan *smp; 1642 u32 value; 1643 int err; 1644 1645 if (!conn) 1646 return -ENOTCONN; 1647 1648 bt_dev_dbg(conn->hcon->hdev, ""); 1649 1650 chan = conn->smp; 1651 if (!chan) 1652 return -ENOTCONN; 1653 1654 l2cap_chan_lock(chan); 1655 if (!chan->data) { 1656 err = -ENOTCONN; 1657 goto unlock; 1658 } 1659 1660 smp = chan->data; 1661 1662 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1663 err = sc_user_reply(smp, mgmt_op, passkey); 1664 goto unlock; 1665 } 1666 1667 switch (mgmt_op) { 1668 case MGMT_OP_USER_PASSKEY_REPLY: 1669 value = le32_to_cpu(passkey); 1670 memset(smp->tk, 0, sizeof(smp->tk)); 1671 bt_dev_dbg(conn->hcon->hdev, "PassKey: %u", value); 1672 put_unaligned_le32(value, smp->tk); 1673 fallthrough; 1674 case MGMT_OP_USER_CONFIRM_REPLY: 1675 set_bit(SMP_FLAG_TK_VALID, &smp->flags); 1676 break; 1677 case MGMT_OP_USER_PASSKEY_NEG_REPLY: 1678 case MGMT_OP_USER_CONFIRM_NEG_REPLY: 1679 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); 1680 err = 0; 1681 goto unlock; 1682 default: 1683 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); 1684 err = -EOPNOTSUPP; 1685 goto unlock; 1686 } 1687 1688 err = 0; 1689 1690 /* If it is our turn to send Pairing Confirm, do so now */ 1691 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) { 1692 u8 rsp = smp_confirm(smp); 1693 if (rsp) 1694 smp_failure(conn, rsp); 1695 } 1696 1697unlock: 1698 l2cap_chan_unlock(chan); 1699 return err; 1700} 1701 1702static void build_bredr_pairing_cmd(struct smp_chan *smp, 1703 struct smp_cmd_pairing *req, 1704 struct smp_cmd_pairing *rsp) 1705{ 1706 struct l2cap_conn *conn = smp->conn; 1707 struct hci_dev *hdev = conn->hcon->hdev; 1708 u8 local_dist = 0, remote_dist = 0; 1709 1710 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) { 1711 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 1712 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 1713 } 1714 1715 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING)) 1716 remote_dist |= SMP_DIST_ID_KEY; 1717 1718 if (hci_dev_test_flag(hdev, HCI_PRIVACY)) 1719 local_dist |= SMP_DIST_ID_KEY; 1720 1721 if (!rsp) { 1722 memset(req, 0, sizeof(*req)); 1723 1724 req->auth_req = SMP_AUTH_CT2; 1725 req->init_key_dist = local_dist; 1726 req->resp_key_dist = remote_dist; 1727 req->max_key_size = conn->hcon->enc_key_size; 1728 1729 smp->remote_key_dist = remote_dist; 1730 1731 return; 1732 } 1733 1734 memset(rsp, 0, sizeof(*rsp)); 1735 1736 rsp->auth_req = SMP_AUTH_CT2; 1737 rsp->max_key_size = conn->hcon->enc_key_size; 1738 rsp->init_key_dist = req->init_key_dist & remote_dist; 1739 rsp->resp_key_dist = req->resp_key_dist & local_dist; 1740 1741 smp->remote_key_dist = rsp->init_key_dist; 1742} 1743 1744static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb) 1745{ 1746 struct smp_cmd_pairing rsp, *req = (void *) skb->data; 1747 struct l2cap_chan *chan = conn->smp; 1748 struct hci_dev *hdev = conn->hcon->hdev; 1749 struct smp_chan *smp; 1750 u8 key_size, auth, sec_level; 1751 int ret; 1752 1753 bt_dev_dbg(hdev, "conn %p", conn); 1754 1755 if (skb->len < sizeof(*req)) 1756 return SMP_INVALID_PARAMS; 1757 1758 if (conn->hcon->role != HCI_ROLE_SLAVE) 1759 return SMP_CMD_NOTSUPP; 1760 1761 if (!chan->data) 1762 smp = smp_chan_create(conn); 1763 else 1764 smp = chan->data; 1765 1766 if (!smp) 1767 return SMP_UNSPECIFIED; 1768 1769 /* We didn't start the pairing, so match remote */ 1770 auth = req->auth_req & AUTH_REQ_MASK(hdev); 1771 1772 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) && 1773 (auth & SMP_AUTH_BONDING)) 1774 return SMP_PAIRING_NOTSUPP; 1775 1776 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 1777 return SMP_AUTH_REQUIREMENTS; 1778 1779 smp->preq[0] = SMP_CMD_PAIRING_REQ; 1780 memcpy(&smp->preq[1], req, sizeof(*req)); 1781 skb_pull(skb, sizeof(*req)); 1782 1783 /* If the remote side's OOB flag is set it means it has 1784 * successfully received our local OOB data - therefore set the 1785 * flag to indicate that local OOB is in use. 1786 */ 1787 if (req->oob_flag == SMP_OOB_PRESENT && SMP_DEV(hdev)->local_oob) 1788 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags); 1789 1790 /* SMP over BR/EDR requires special treatment */ 1791 if (conn->hcon->type == ACL_LINK) { 1792 /* We must have a BR/EDR SC link */ 1793 if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) && 1794 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 1795 return SMP_CROSS_TRANSP_NOT_ALLOWED; 1796 1797 set_bit(SMP_FLAG_SC, &smp->flags); 1798 1799 build_bredr_pairing_cmd(smp, req, &rsp); 1800 1801 if (req->auth_req & SMP_AUTH_CT2) 1802 set_bit(SMP_FLAG_CT2, &smp->flags); 1803 1804 key_size = min(req->max_key_size, rsp.max_key_size); 1805 if (check_enc_key_size(conn, key_size)) 1806 return SMP_ENC_KEY_SIZE; 1807 1808 /* Clear bits which are generated but not distributed */ 1809 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1810 1811 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1812 memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); 1813 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); 1814 1815 smp_distribute_keys(smp); 1816 return 0; 1817 } 1818 1819 build_pairing_cmd(conn, req, &rsp, auth); 1820 1821 if (rsp.auth_req & SMP_AUTH_SC) { 1822 set_bit(SMP_FLAG_SC, &smp->flags); 1823 1824 if (rsp.auth_req & SMP_AUTH_CT2) 1825 set_bit(SMP_FLAG_CT2, &smp->flags); 1826 } 1827 1828 if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 1829 sec_level = BT_SECURITY_MEDIUM; 1830 else 1831 sec_level = authreq_to_seclevel(auth); 1832 1833 if (sec_level > conn->hcon->pending_sec_level) 1834 conn->hcon->pending_sec_level = sec_level; 1835 1836 /* If we need MITM check that it can be achieved */ 1837 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { 1838 u8 method; 1839 1840 method = get_auth_method(smp, conn->hcon->io_capability, 1841 req->io_capability); 1842 if (method == JUST_WORKS || method == JUST_CFM) 1843 return SMP_AUTH_REQUIREMENTS; 1844 } 1845 1846 key_size = min(req->max_key_size, rsp.max_key_size); 1847 if (check_enc_key_size(conn, key_size)) 1848 return SMP_ENC_KEY_SIZE; 1849 1850 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 1851 1852 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1853 memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); 1854 1855 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); 1856 1857 clear_bit(SMP_FLAG_INITIATOR, &smp->flags); 1858 1859 /* Strictly speaking we shouldn't allow Pairing Confirm for the 1860 * SC case, however some implementations incorrectly copy RFU auth 1861 * req bits from our security request, which may create a false 1862 * positive SC enablement. 1863 */ 1864 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1865 1866 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1867 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY); 1868 /* Clear bits which are generated but not distributed */ 1869 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1870 /* Wait for Public Key from Initiating Device */ 1871 return 0; 1872 } 1873 1874 /* Request setup of TK */ 1875 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability); 1876 if (ret) 1877 return SMP_UNSPECIFIED; 1878 1879 return 0; 1880} 1881 1882static u8 sc_send_public_key(struct smp_chan *smp) 1883{ 1884 struct hci_dev *hdev = smp->conn->hcon->hdev; 1885 1886 bt_dev_dbg(hdev, ""); 1887 1888 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) { 1889 struct l2cap_chan *chan = hdev->smp_data; 1890 struct smp_dev *smp_dev; 1891 1892 if (!chan || !chan->data) 1893 return SMP_UNSPECIFIED; 1894 1895 smp_dev = chan->data; 1896 1897 memcpy(smp->local_pk, smp_dev->local_pk, 64); 1898 memcpy(smp->lr, smp_dev->local_rand, 16); 1899 1900 if (smp_dev->debug_key) 1901 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1902 1903 goto done; 1904 } 1905 1906 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) { 1907 bt_dev_dbg(hdev, "Using debug keys"); 1908 if (set_ecdh_privkey(smp->tfm_ecdh, debug_sk)) 1909 return SMP_UNSPECIFIED; 1910 memcpy(smp->local_pk, debug_pk, 64); 1911 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1912 } else { 1913 while (true) { 1914 /* Generate key pair for Secure Connections */ 1915 if (generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk)) 1916 return SMP_UNSPECIFIED; 1917 1918 /* This is unlikely, but we need to check that 1919 * we didn't accidentally generate a debug key. 1920 */ 1921 if (crypto_memneq(smp->local_pk, debug_pk, 64)) 1922 break; 1923 } 1924 } 1925 1926done: 1927 SMP_DBG("Local Public Key X: %32phN", smp->local_pk); 1928 SMP_DBG("Local Public Key Y: %32phN", smp->local_pk + 32); 1929 1930 smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk); 1931 1932 return 0; 1933} 1934 1935static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb) 1936{ 1937 struct smp_cmd_pairing *req, *rsp = (void *) skb->data; 1938 struct l2cap_chan *chan = conn->smp; 1939 struct smp_chan *smp = chan->data; 1940 struct hci_dev *hdev = conn->hcon->hdev; 1941 u8 key_size, auth; 1942 int ret; 1943 1944 bt_dev_dbg(hdev, "conn %p", conn); 1945 1946 if (skb->len < sizeof(*rsp)) 1947 return SMP_INVALID_PARAMS; 1948 1949 if (conn->hcon->role != HCI_ROLE_MASTER) 1950 return SMP_CMD_NOTSUPP; 1951 1952 skb_pull(skb, sizeof(*rsp)); 1953 1954 req = (void *) &smp->preq[1]; 1955 1956 key_size = min(req->max_key_size, rsp->max_key_size); 1957 if (check_enc_key_size(conn, key_size)) 1958 return SMP_ENC_KEY_SIZE; 1959 1960 auth = rsp->auth_req & AUTH_REQ_MASK(hdev); 1961 1962 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 1963 return SMP_AUTH_REQUIREMENTS; 1964 1965 /* If the remote side's OOB flag is set it means it has 1966 * successfully received our local OOB data - therefore set the 1967 * flag to indicate that local OOB is in use. 1968 */ 1969 if (rsp->oob_flag == SMP_OOB_PRESENT && SMP_DEV(hdev)->local_oob) 1970 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags); 1971 1972 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1973 memcpy(&smp->prsp[1], rsp, sizeof(*rsp)); 1974 1975 /* Update remote key distribution in case the remote cleared 1976 * some bits that we had enabled in our request. 1977 */ 1978 smp->remote_key_dist &= rsp->resp_key_dist; 1979 1980 if ((req->auth_req & SMP_AUTH_CT2) && (auth & SMP_AUTH_CT2)) 1981 set_bit(SMP_FLAG_CT2, &smp->flags); 1982 1983 /* For BR/EDR this means we're done and can start phase 3 */ 1984 if (conn->hcon->type == ACL_LINK) { 1985 /* Clear bits which are generated but not distributed */ 1986 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1987 smp_distribute_keys(smp); 1988 return 0; 1989 } 1990 1991 if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC)) 1992 set_bit(SMP_FLAG_SC, &smp->flags); 1993 else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH) 1994 conn->hcon->pending_sec_level = BT_SECURITY_HIGH; 1995 1996 /* If we need MITM check that it can be achieved */ 1997 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { 1998 u8 method; 1999 2000 method = get_auth_method(smp, req->io_capability, 2001 rsp->io_capability); 2002 if (method == JUST_WORKS || method == JUST_CFM) 2003 return SMP_AUTH_REQUIREMENTS; 2004 } 2005 2006 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 2007 2008 /* Update remote key distribution in case the remote cleared 2009 * some bits that we had enabled in our request. 2010 */ 2011 smp->remote_key_dist &= rsp->resp_key_dist; 2012 2013 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 2014 /* Clear bits which are generated but not distributed */ 2015 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 2016 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY); 2017 return sc_send_public_key(smp); 2018 } 2019 2020 auth |= req->auth_req; 2021 2022 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability); 2023 if (ret) 2024 return SMP_UNSPECIFIED; 2025 2026 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 2027 2028 /* Can't compose response until we have been confirmed */ 2029 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) 2030 return smp_confirm(smp); 2031 2032 return 0; 2033} 2034 2035static u8 sc_check_confirm(struct smp_chan *smp) 2036{ 2037 struct l2cap_conn *conn = smp->conn; 2038 2039 bt_dev_dbg(conn->hcon->hdev, ""); 2040 2041 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2042 return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM); 2043 2044 if (conn->hcon->out) { 2045 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2046 smp->prnd); 2047 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2048 } 2049 2050 return 0; 2051} 2052 2053/* Work-around for some implementations that incorrectly copy RFU bits 2054 * from our security request and thereby create the impression that 2055 * we're doing SC when in fact the remote doesn't support it. 2056 */ 2057static int fixup_sc_false_positive(struct smp_chan *smp) 2058{ 2059 struct l2cap_conn *conn = smp->conn; 2060 struct hci_conn *hcon = conn->hcon; 2061 struct hci_dev *hdev = hcon->hdev; 2062 struct smp_cmd_pairing *req, *rsp; 2063 u8 auth; 2064 2065 /* The issue is only observed when we're in responder role */ 2066 if (hcon->out) 2067 return SMP_UNSPECIFIED; 2068 2069 if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) { 2070 bt_dev_err(hdev, "refusing legacy fallback in SC-only mode"); 2071 return SMP_UNSPECIFIED; 2072 } 2073 2074 bt_dev_err(hdev, "trying to fall back to legacy SMP"); 2075 2076 req = (void *) &smp->preq[1]; 2077 rsp = (void *) &smp->prsp[1]; 2078 2079 /* Rebuild key dist flags which may have been cleared for SC */ 2080 smp->remote_key_dist = (req->init_key_dist & rsp->resp_key_dist); 2081 2082 auth = req->auth_req & AUTH_REQ_MASK(hdev); 2083 2084 if (tk_request(conn, 0, auth, rsp->io_capability, req->io_capability)) { 2085 bt_dev_err(hdev, "failed to fall back to legacy SMP"); 2086 return SMP_UNSPECIFIED; 2087 } 2088 2089 clear_bit(SMP_FLAG_SC, &smp->flags); 2090 2091 return 0; 2092} 2093 2094static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb) 2095{ 2096 struct l2cap_chan *chan = conn->smp; 2097 struct smp_chan *smp = chan->data; 2098 struct hci_conn *hcon = conn->hcon; 2099 struct hci_dev *hdev = hcon->hdev; 2100 2101 bt_dev_dbg(hdev, "conn %p %s", conn, 2102 hcon->out ? "initiator" : "responder"); 2103 2104 if (skb->len < sizeof(smp->pcnf)) 2105 return SMP_INVALID_PARAMS; 2106 2107 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf)); 2108 skb_pull(skb, sizeof(smp->pcnf)); 2109 2110 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 2111 int ret; 2112 2113 /* Public Key exchange must happen before any other steps */ 2114 if (test_bit(SMP_FLAG_REMOTE_PK, &smp->flags)) 2115 return sc_check_confirm(smp); 2116 2117 bt_dev_err(hdev, "Unexpected SMP Pairing Confirm"); 2118 2119 ret = fixup_sc_false_positive(smp); 2120 if (ret) 2121 return ret; 2122 } 2123 2124 if (conn->hcon->out) { 2125 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2126 smp->prnd); 2127 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2128 return 0; 2129 } 2130 2131 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) 2132 return smp_confirm(smp); 2133 2134 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 2135 2136 return 0; 2137} 2138 2139static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb) 2140{ 2141 struct l2cap_chan *chan = conn->smp; 2142 struct smp_chan *smp = chan->data; 2143 struct hci_conn *hcon = conn->hcon; 2144 u8 *pkax, *pkbx, *na, *nb, confirm_hint; 2145 u32 passkey; 2146 int err; 2147 2148 bt_dev_dbg(hcon->hdev, "conn %p", conn); 2149 2150 if (skb->len < sizeof(smp->rrnd)) 2151 return SMP_INVALID_PARAMS; 2152 2153 memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd)); 2154 skb_pull(skb, sizeof(smp->rrnd)); 2155 2156 if (!test_bit(SMP_FLAG_SC, &smp->flags)) 2157 return smp_random(smp); 2158 2159 if (hcon->out) { 2160 pkax = smp->local_pk; 2161 pkbx = smp->remote_pk; 2162 na = smp->prnd; 2163 nb = smp->rrnd; 2164 } else { 2165 pkax = smp->remote_pk; 2166 pkbx = smp->local_pk; 2167 na = smp->rrnd; 2168 nb = smp->prnd; 2169 } 2170 2171 if (smp->method == REQ_OOB) { 2172 if (!hcon->out) 2173 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 2174 sizeof(smp->prnd), smp->prnd); 2175 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2176 goto mackey_and_ltk; 2177 } 2178 2179 /* Passkey entry has special treatment */ 2180 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2181 return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM); 2182 2183 if (hcon->out) { 2184 u8 cfm[16]; 2185 2186 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk, 2187 smp->rrnd, 0, cfm); 2188 if (err) 2189 return SMP_UNSPECIFIED; 2190 2191 if (crypto_memneq(smp->pcnf, cfm, 16)) 2192 return SMP_CONFIRM_FAILED; 2193 } else { 2194 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2195 smp->prnd); 2196 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2197 2198 /* Only Just-Works pairing requires extra checks */ 2199 if (smp->method != JUST_WORKS) 2200 goto mackey_and_ltk; 2201 2202 /* If there already exists long term key in local host, leave 2203 * the decision to user space since the remote device could 2204 * be legitimate or malicious. 2205 */ 2206 if (hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, 2207 hcon->role)) { 2208 /* Set passkey to 0. The value can be any number since 2209 * it'll be ignored anyway. 2210 */ 2211 passkey = 0; 2212 confirm_hint = 1; 2213 goto confirm; 2214 } 2215 } 2216 2217mackey_and_ltk: 2218 /* Generate MacKey and LTK */ 2219 err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk); 2220 if (err) 2221 return SMP_UNSPECIFIED; 2222 2223 if (smp->method == REQ_OOB) { 2224 if (hcon->out) { 2225 sc_dhkey_check(smp); 2226 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2227 } 2228 return 0; 2229 } 2230 2231 err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey); 2232 if (err) 2233 return SMP_UNSPECIFIED; 2234 2235 confirm_hint = 0; 2236 2237confirm: 2238 if (smp->method == JUST_WORKS) 2239 confirm_hint = 1; 2240 2241 err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type, 2242 hcon->dst_type, passkey, confirm_hint); 2243 if (err) 2244 return SMP_UNSPECIFIED; 2245 2246 set_bit(SMP_FLAG_WAIT_USER, &smp->flags); 2247 2248 return 0; 2249} 2250 2251static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level) 2252{ 2253 struct smp_ltk *key; 2254 struct hci_conn *hcon = conn->hcon; 2255 2256 key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role); 2257 if (!key) 2258 return false; 2259 2260 if (smp_ltk_sec_level(key) < sec_level) 2261 return false; 2262 2263 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) 2264 return true; 2265 2266 hci_le_start_enc(hcon, key->ediv, key->rand, key->val, key->enc_size); 2267 hcon->enc_key_size = key->enc_size; 2268 2269 /* We never store STKs for initiator role, so clear this flag */ 2270 clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); 2271 2272 return true; 2273} 2274 2275bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level, 2276 enum smp_key_pref key_pref) 2277{ 2278 if (sec_level == BT_SECURITY_LOW) 2279 return true; 2280 2281 /* If we're encrypted with an STK but the caller prefers using 2282 * LTK claim insufficient security. This way we allow the 2283 * connection to be re-encrypted with an LTK, even if the LTK 2284 * provides the same level of security. Only exception is if we 2285 * don't have an LTK (e.g. because of key distribution bits). 2286 */ 2287 if (key_pref == SMP_USE_LTK && 2288 test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) && 2289 hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role)) 2290 return false; 2291 2292 if (hcon->sec_level >= sec_level) 2293 return true; 2294 2295 return false; 2296} 2297 2298static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb) 2299{ 2300 struct smp_cmd_security_req *rp = (void *) skb->data; 2301 struct smp_cmd_pairing cp; 2302 struct hci_conn *hcon = conn->hcon; 2303 struct hci_dev *hdev = hcon->hdev; 2304 struct smp_chan *smp; 2305 u8 sec_level, auth; 2306 2307 bt_dev_dbg(hdev, "conn %p", conn); 2308 2309 if (skb->len < sizeof(*rp)) 2310 return SMP_INVALID_PARAMS; 2311 2312 if (hcon->role != HCI_ROLE_MASTER) 2313 return SMP_CMD_NOTSUPP; 2314 2315 auth = rp->auth_req & AUTH_REQ_MASK(hdev); 2316 2317 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 2318 return SMP_AUTH_REQUIREMENTS; 2319 2320 if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 2321 sec_level = BT_SECURITY_MEDIUM; 2322 else 2323 sec_level = authreq_to_seclevel(auth); 2324 2325 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) { 2326 /* If link is already encrypted with sufficient security we 2327 * still need refresh encryption as per Core Spec 5.0 Vol 3, 2328 * Part H 2.4.6 2329 */ 2330 smp_ltk_encrypt(conn, hcon->sec_level); 2331 return 0; 2332 } 2333 2334 if (sec_level > hcon->pending_sec_level) 2335 hcon->pending_sec_level = sec_level; 2336 2337 if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) 2338 return 0; 2339 2340 smp = smp_chan_create(conn); 2341 if (!smp) 2342 return SMP_UNSPECIFIED; 2343 2344 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) && 2345 (auth & SMP_AUTH_BONDING)) 2346 return SMP_PAIRING_NOTSUPP; 2347 2348 skb_pull(skb, sizeof(*rp)); 2349 2350 memset(&cp, 0, sizeof(cp)); 2351 build_pairing_cmd(conn, &cp, NULL, auth); 2352 2353 smp->preq[0] = SMP_CMD_PAIRING_REQ; 2354 memcpy(&smp->preq[1], &cp, sizeof(cp)); 2355 2356 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); 2357 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 2358 2359 return 0; 2360} 2361 2362int smp_conn_security(struct hci_conn *hcon, __u8 sec_level) 2363{ 2364 struct l2cap_conn *conn = hcon->l2cap_data; 2365 struct l2cap_chan *chan; 2366 struct smp_chan *smp; 2367 __u8 authreq; 2368 int ret; 2369 2370 bt_dev_dbg(hcon->hdev, "conn %p hcon %p level 0x%2.2x", conn, hcon, 2371 sec_level); 2372 2373 /* This may be NULL if there's an unexpected disconnection */ 2374 if (!conn) 2375 return 1; 2376 2377 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) 2378 return 1; 2379 2380 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) 2381 return 1; 2382 2383 if (sec_level > hcon->pending_sec_level) 2384 hcon->pending_sec_level = sec_level; 2385 2386 if (hcon->role == HCI_ROLE_MASTER) 2387 if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) 2388 return 0; 2389 2390 chan = conn->smp; 2391 if (!chan) { 2392 bt_dev_err(hcon->hdev, "security requested but not available"); 2393 return 1; 2394 } 2395 2396 l2cap_chan_lock(chan); 2397 2398 /* If SMP is already in progress ignore this request */ 2399 if (chan->data) { 2400 ret = 0; 2401 goto unlock; 2402 } 2403 2404 smp = smp_chan_create(conn); 2405 if (!smp) { 2406 ret = 1; 2407 goto unlock; 2408 } 2409 2410 authreq = seclevel_to_authreq(sec_level); 2411 2412 if (hci_dev_test_flag(hcon->hdev, HCI_SC_ENABLED)) { 2413 authreq |= SMP_AUTH_SC; 2414 if (hci_dev_test_flag(hcon->hdev, HCI_SSP_ENABLED)) 2415 authreq |= SMP_AUTH_CT2; 2416 } 2417 2418 /* Don't attempt to set MITM if setting is overridden by debugfs 2419 * Needed to pass certification test SM/MAS/PKE/BV-01-C 2420 */ 2421 if (!hci_dev_test_flag(hcon->hdev, HCI_FORCE_NO_MITM)) { 2422 /* Require MITM if IO Capability allows or the security level 2423 * requires it. 2424 */ 2425 if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT || 2426 hcon->pending_sec_level > BT_SECURITY_MEDIUM) 2427 authreq |= SMP_AUTH_MITM; 2428 } 2429 2430 if (hcon->role == HCI_ROLE_MASTER) { 2431 struct smp_cmd_pairing cp; 2432 2433 build_pairing_cmd(conn, &cp, NULL, authreq); 2434 smp->preq[0] = SMP_CMD_PAIRING_REQ; 2435 memcpy(&smp->preq[1], &cp, sizeof(cp)); 2436 2437 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); 2438 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 2439 } else { 2440 struct smp_cmd_security_req cp; 2441 cp.auth_req = authreq; 2442 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp); 2443 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ); 2444 } 2445 2446 set_bit(SMP_FLAG_INITIATOR, &smp->flags); 2447 ret = 0; 2448 2449unlock: 2450 l2cap_chan_unlock(chan); 2451 return ret; 2452} 2453 2454int smp_cancel_and_remove_pairing(struct hci_dev *hdev, bdaddr_t *bdaddr, 2455 u8 addr_type) 2456{ 2457 struct hci_conn *hcon; 2458 struct l2cap_conn *conn; 2459 struct l2cap_chan *chan; 2460 struct smp_chan *smp; 2461 int err; 2462 2463 err = hci_remove_ltk(hdev, bdaddr, addr_type); 2464 hci_remove_irk(hdev, bdaddr, addr_type); 2465 2466 hcon = hci_conn_hash_lookup_le(hdev, bdaddr, addr_type); 2467 if (!hcon) 2468 goto done; 2469 2470 conn = hcon->l2cap_data; 2471 if (!conn) 2472 goto done; 2473 2474 chan = conn->smp; 2475 if (!chan) 2476 goto done; 2477 2478 l2cap_chan_lock(chan); 2479 2480 smp = chan->data; 2481 if (smp) { 2482 /* Set keys to NULL to make sure smp_failure() does not try to 2483 * remove and free already invalidated rcu list entries. */ 2484 smp->ltk = NULL; 2485 smp->responder_ltk = NULL; 2486 smp->remote_irk = NULL; 2487 2488 if (test_bit(SMP_FLAG_COMPLETE, &smp->flags)) 2489 smp_failure(conn, 0); 2490 else 2491 smp_failure(conn, SMP_UNSPECIFIED); 2492 err = 0; 2493 } 2494 2495 l2cap_chan_unlock(chan); 2496 2497done: 2498 return err; 2499} 2500 2501static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb) 2502{ 2503 struct smp_cmd_encrypt_info *rp = (void *) skb->data; 2504 struct l2cap_chan *chan = conn->smp; 2505 struct smp_chan *smp = chan->data; 2506 2507 bt_dev_dbg(conn->hcon->hdev, "conn %p", conn); 2508 2509 if (skb->len < sizeof(*rp)) 2510 return SMP_INVALID_PARAMS; 2511 2512 /* Pairing is aborted if any blocked keys are distributed */ 2513 if (hci_is_blocked_key(conn->hcon->hdev, HCI_BLOCKED_KEY_TYPE_LTK, 2514 rp->ltk)) { 2515 bt_dev_warn_ratelimited(conn->hcon->hdev, 2516 "LTK blocked for %pMR", 2517 &conn->hcon->dst); 2518 return SMP_INVALID_PARAMS; 2519 } 2520 2521 SMP_ALLOW_CMD(smp, SMP_CMD_INITIATOR_IDENT); 2522 2523 skb_pull(skb, sizeof(*rp)); 2524 2525 memcpy(smp->tk, rp->ltk, sizeof(smp->tk)); 2526 2527 return 0; 2528} 2529 2530static int smp_cmd_initiator_ident(struct l2cap_conn *conn, struct sk_buff *skb) 2531{ 2532 struct smp_cmd_initiator_ident *rp = (void *)skb->data; 2533 struct l2cap_chan *chan = conn->smp; 2534 struct smp_chan *smp = chan->data; 2535 struct hci_dev *hdev = conn->hcon->hdev; 2536 struct hci_conn *hcon = conn->hcon; 2537 struct smp_ltk *ltk; 2538 u8 authenticated; 2539 2540 bt_dev_dbg(hdev, "conn %p", conn); 2541 2542 if (skb->len < sizeof(*rp)) 2543 return SMP_INVALID_PARAMS; 2544 2545 /* Mark the information as received */ 2546 smp->remote_key_dist &= ~SMP_DIST_ENC_KEY; 2547 2548 if (smp->remote_key_dist & SMP_DIST_ID_KEY) 2549 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); 2550 else if (smp->remote_key_dist & SMP_DIST_SIGN) 2551 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 2552 2553 skb_pull(skb, sizeof(*rp)); 2554 2555 authenticated = (hcon->sec_level == BT_SECURITY_HIGH); 2556 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK, 2557 authenticated, smp->tk, smp->enc_key_size, 2558 rp->ediv, rp->rand); 2559 smp->ltk = ltk; 2560 if (!(smp->remote_key_dist & KEY_DIST_MASK)) 2561 smp_distribute_keys(smp); 2562 2563 return 0; 2564} 2565 2566static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb) 2567{ 2568 struct smp_cmd_ident_info *info = (void *) skb->data; 2569 struct l2cap_chan *chan = conn->smp; 2570 struct smp_chan *smp = chan->data; 2571 2572 bt_dev_dbg(conn->hcon->hdev, ""); 2573 2574 if (skb->len < sizeof(*info)) 2575 return SMP_INVALID_PARAMS; 2576 2577 /* Pairing is aborted if any blocked keys are distributed */ 2578 if (hci_is_blocked_key(conn->hcon->hdev, HCI_BLOCKED_KEY_TYPE_IRK, 2579 info->irk)) { 2580 bt_dev_warn_ratelimited(conn->hcon->hdev, 2581 "Identity key blocked for %pMR", 2582 &conn->hcon->dst); 2583 return SMP_INVALID_PARAMS; 2584 } 2585 2586 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO); 2587 2588 skb_pull(skb, sizeof(*info)); 2589 2590 memcpy(smp->irk, info->irk, 16); 2591 2592 return 0; 2593} 2594 2595static int smp_cmd_ident_addr_info(struct l2cap_conn *conn, 2596 struct sk_buff *skb) 2597{ 2598 struct smp_cmd_ident_addr_info *info = (void *) skb->data; 2599 struct l2cap_chan *chan = conn->smp; 2600 struct smp_chan *smp = chan->data; 2601 struct hci_conn *hcon = conn->hcon; 2602 bdaddr_t rpa; 2603 2604 bt_dev_dbg(hcon->hdev, ""); 2605 2606 if (skb->len < sizeof(*info)) 2607 return SMP_INVALID_PARAMS; 2608 2609 /* Mark the information as received */ 2610 smp->remote_key_dist &= ~SMP_DIST_ID_KEY; 2611 2612 if (smp->remote_key_dist & SMP_DIST_SIGN) 2613 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 2614 2615 skb_pull(skb, sizeof(*info)); 2616 2617 /* Strictly speaking the Core Specification (4.1) allows sending 2618 * an empty address which would force us to rely on just the IRK 2619 * as "identity information". However, since such 2620 * implementations are not known of and in order to not over 2621 * complicate our implementation, simply pretend that we never 2622 * received an IRK for such a device. 2623 * 2624 * The Identity Address must also be a Static Random or Public 2625 * Address, which hci_is_identity_address() checks for. 2626 */ 2627 if (!bacmp(&info->bdaddr, BDADDR_ANY) || 2628 !hci_is_identity_address(&info->bdaddr, info->addr_type)) { 2629 bt_dev_err(hcon->hdev, "ignoring IRK with no identity address"); 2630 goto distribute; 2631 } 2632 2633 /* Drop IRK if peer is using identity address during pairing but is 2634 * providing different address as identity information. 2635 * 2636 * Microsoft Surface Precision Mouse is known to have this bug. 2637 */ 2638 if (hci_is_identity_address(&hcon->dst, hcon->dst_type) && 2639 (bacmp(&info->bdaddr, &hcon->dst) || 2640 info->addr_type != hcon->dst_type)) { 2641 bt_dev_err(hcon->hdev, 2642 "ignoring IRK with invalid identity address"); 2643 goto distribute; 2644 } 2645 2646 bacpy(&smp->id_addr, &info->bdaddr); 2647 smp->id_addr_type = info->addr_type; 2648 2649 if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type)) 2650 bacpy(&rpa, &hcon->dst); 2651 else 2652 bacpy(&rpa, BDADDR_ANY); 2653 2654 smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr, 2655 smp->id_addr_type, smp->irk, &rpa); 2656 2657distribute: 2658 if (!(smp->remote_key_dist & KEY_DIST_MASK)) 2659 smp_distribute_keys(smp); 2660 2661 return 0; 2662} 2663 2664static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb) 2665{ 2666 struct smp_cmd_sign_info *rp = (void *) skb->data; 2667 struct l2cap_chan *chan = conn->smp; 2668 struct smp_chan *smp = chan->data; 2669 struct smp_csrk *csrk; 2670 2671 bt_dev_dbg(conn->hcon->hdev, "conn %p", conn); 2672 2673 if (skb->len < sizeof(*rp)) 2674 return SMP_INVALID_PARAMS; 2675 2676 /* Mark the information as received */ 2677 smp->remote_key_dist &= ~SMP_DIST_SIGN; 2678 2679 skb_pull(skb, sizeof(*rp)); 2680 2681 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); 2682 if (csrk) { 2683 if (conn->hcon->sec_level > BT_SECURITY_MEDIUM) 2684 csrk->type = MGMT_CSRK_REMOTE_AUTHENTICATED; 2685 else 2686 csrk->type = MGMT_CSRK_REMOTE_UNAUTHENTICATED; 2687 memcpy(csrk->val, rp->csrk, sizeof(csrk->val)); 2688 } 2689 smp->csrk = csrk; 2690 smp_distribute_keys(smp); 2691 2692 return 0; 2693} 2694 2695static u8 sc_select_method(struct smp_chan *smp) 2696{ 2697 struct l2cap_conn *conn = smp->conn; 2698 struct hci_conn *hcon = conn->hcon; 2699 struct smp_cmd_pairing *local, *remote; 2700 u8 local_mitm, remote_mitm, local_io, remote_io, method; 2701 2702 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags) || 2703 test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) 2704 return REQ_OOB; 2705 2706 /* The preq/prsp contain the raw Pairing Request/Response PDUs 2707 * which are needed as inputs to some crypto functions. To get 2708 * the "struct smp_cmd_pairing" from them we need to skip the 2709 * first byte which contains the opcode. 2710 */ 2711 if (hcon->out) { 2712 local = (void *) &smp->preq[1]; 2713 remote = (void *) &smp->prsp[1]; 2714 } else { 2715 local = (void *) &smp->prsp[1]; 2716 remote = (void *) &smp->preq[1]; 2717 } 2718 2719 local_io = local->io_capability; 2720 remote_io = remote->io_capability; 2721 2722 local_mitm = (local->auth_req & SMP_AUTH_MITM); 2723 remote_mitm = (remote->auth_req & SMP_AUTH_MITM); 2724 2725 /* If either side wants MITM, look up the method from the table, 2726 * otherwise use JUST WORKS. 2727 */ 2728 if (local_mitm || remote_mitm) 2729 method = get_auth_method(smp, local_io, remote_io); 2730 else 2731 method = JUST_WORKS; 2732 2733 /* Don't confirm locally initiated pairing attempts */ 2734 if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags)) 2735 method = JUST_WORKS; 2736 2737 return method; 2738} 2739 2740static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb) 2741{ 2742 struct smp_cmd_public_key *key = (void *) skb->data; 2743 struct hci_conn *hcon = conn->hcon; 2744 struct l2cap_chan *chan = conn->smp; 2745 struct smp_chan *smp = chan->data; 2746 struct hci_dev *hdev = hcon->hdev; 2747 struct crypto_kpp *tfm_ecdh; 2748 struct smp_cmd_pairing_confirm cfm; 2749 int err; 2750 2751 bt_dev_dbg(hdev, "conn %p", conn); 2752 2753 if (skb->len < sizeof(*key)) 2754 return SMP_INVALID_PARAMS; 2755 2756 /* Check if remote and local public keys are the same and debug key is 2757 * not in use. 2758 */ 2759 if (!test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags) && 2760 !crypto_memneq(key, smp->local_pk, 64)) { 2761 bt_dev_err(hdev, "Remote and local public keys are identical"); 2762 return SMP_UNSPECIFIED; 2763 } 2764 2765 memcpy(smp->remote_pk, key, 64); 2766 2767 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags)) { 2768 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk, 2769 smp->rr, 0, cfm.confirm_val); 2770 if (err) 2771 return SMP_UNSPECIFIED; 2772 2773 if (crypto_memneq(cfm.confirm_val, smp->pcnf, 16)) 2774 return SMP_CONFIRM_FAILED; 2775 } 2776 2777 /* Non-initiating device sends its public key after receiving 2778 * the key from the initiating device. 2779 */ 2780 if (!hcon->out) { 2781 err = sc_send_public_key(smp); 2782 if (err) 2783 return err; 2784 } 2785 2786 SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk); 2787 SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32); 2788 2789 /* Compute the shared secret on the same crypto tfm on which the private 2790 * key was set/generated. 2791 */ 2792 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) { 2793 struct l2cap_chan *hchan = hdev->smp_data; 2794 struct smp_dev *smp_dev; 2795 2796 if (!hchan || !hchan->data) 2797 return SMP_UNSPECIFIED; 2798 2799 smp_dev = hchan->data; 2800 2801 tfm_ecdh = smp_dev->tfm_ecdh; 2802 } else { 2803 tfm_ecdh = smp->tfm_ecdh; 2804 } 2805 2806 if (compute_ecdh_secret(tfm_ecdh, smp->remote_pk, smp->dhkey)) 2807 return SMP_UNSPECIFIED; 2808 2809 SMP_DBG("DHKey %32phN", smp->dhkey); 2810 2811 set_bit(SMP_FLAG_REMOTE_PK, &smp->flags); 2812 2813 smp->method = sc_select_method(smp); 2814 2815 bt_dev_dbg(hdev, "selected method 0x%02x", smp->method); 2816 2817 /* JUST_WORKS and JUST_CFM result in an unauthenticated key */ 2818 if (smp->method == JUST_WORKS || smp->method == JUST_CFM) 2819 hcon->pending_sec_level = BT_SECURITY_MEDIUM; 2820 else 2821 hcon->pending_sec_level = BT_SECURITY_FIPS; 2822 2823 if (!crypto_memneq(debug_pk, smp->remote_pk, 64)) 2824 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 2825 2826 if (smp->method == DSP_PASSKEY) { 2827 get_random_bytes(&hcon->passkey_notify, 2828 sizeof(hcon->passkey_notify)); 2829 hcon->passkey_notify %= 1000000; 2830 hcon->passkey_entered = 0; 2831 smp->passkey_round = 0; 2832 if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type, 2833 hcon->dst_type, 2834 hcon->passkey_notify, 2835 hcon->passkey_entered)) 2836 return SMP_UNSPECIFIED; 2837 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2838 return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY); 2839 } 2840 2841 if (smp->method == REQ_OOB) { 2842 if (hcon->out) 2843 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 2844 sizeof(smp->prnd), smp->prnd); 2845 2846 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2847 2848 return 0; 2849 } 2850 2851 if (hcon->out) 2852 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2853 2854 if (smp->method == REQ_PASSKEY) { 2855 if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type, 2856 hcon->dst_type)) 2857 return SMP_UNSPECIFIED; 2858 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2859 set_bit(SMP_FLAG_WAIT_USER, &smp->flags); 2860 return 0; 2861 } 2862 2863 /* The Initiating device waits for the non-initiating device to 2864 * send the confirm value. 2865 */ 2866 if (conn->hcon->out) 2867 return 0; 2868 2869 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, 2870 0, cfm.confirm_val); 2871 if (err) 2872 return SMP_UNSPECIFIED; 2873 2874 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm); 2875 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2876 2877 return 0; 2878} 2879 2880static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb) 2881{ 2882 struct smp_cmd_dhkey_check *check = (void *) skb->data; 2883 struct l2cap_chan *chan = conn->smp; 2884 struct hci_conn *hcon = conn->hcon; 2885 struct smp_chan *smp = chan->data; 2886 u8 a[7], b[7], *local_addr, *remote_addr; 2887 u8 io_cap[3], r[16], e[16]; 2888 int err; 2889 2890 bt_dev_dbg(hcon->hdev, "conn %p", conn); 2891 2892 if (skb->len < sizeof(*check)) 2893 return SMP_INVALID_PARAMS; 2894 2895 memcpy(a, &hcon->init_addr, 6); 2896 memcpy(b, &hcon->resp_addr, 6); 2897 a[6] = hcon->init_addr_type; 2898 b[6] = hcon->resp_addr_type; 2899 2900 if (hcon->out) { 2901 local_addr = a; 2902 remote_addr = b; 2903 memcpy(io_cap, &smp->prsp[1], 3); 2904 } else { 2905 local_addr = b; 2906 remote_addr = a; 2907 memcpy(io_cap, &smp->preq[1], 3); 2908 } 2909 2910 memset(r, 0, sizeof(r)); 2911 2912 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2913 put_unaligned_le32(hcon->passkey_notify, r); 2914 else if (smp->method == REQ_OOB) 2915 memcpy(r, smp->lr, 16); 2916 2917 err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r, 2918 io_cap, remote_addr, local_addr, e); 2919 if (err) 2920 return SMP_UNSPECIFIED; 2921 2922 if (crypto_memneq(check->e, e, 16)) 2923 return SMP_DHKEY_CHECK_FAILED; 2924 2925 if (!hcon->out) { 2926 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) { 2927 set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags); 2928 return 0; 2929 } 2930 2931 /* Responder sends DHKey check as response to initiator */ 2932 sc_dhkey_check(smp); 2933 } 2934 2935 sc_add_ltk(smp); 2936 2937 if (hcon->out) { 2938 hci_le_start_enc(hcon, 0, 0, smp->tk, smp->enc_key_size); 2939 hcon->enc_key_size = smp->enc_key_size; 2940 } 2941 2942 return 0; 2943} 2944 2945static int smp_cmd_keypress_notify(struct l2cap_conn *conn, 2946 struct sk_buff *skb) 2947{ 2948 struct smp_cmd_keypress_notify *kp = (void *) skb->data; 2949 2950 bt_dev_dbg(conn->hcon->hdev, "value 0x%02x", kp->value); 2951 2952 return 0; 2953} 2954 2955static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb) 2956{ 2957 struct l2cap_conn *conn = chan->conn; 2958 struct hci_conn *hcon = conn->hcon; 2959 struct smp_chan *smp; 2960 __u8 code, reason; 2961 int err = 0; 2962 2963 if (skb->len < 1) 2964 return -EILSEQ; 2965 2966 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) { 2967 reason = SMP_PAIRING_NOTSUPP; 2968 goto done; 2969 } 2970 2971 code = skb->data[0]; 2972 skb_pull(skb, sizeof(code)); 2973 2974 smp = chan->data; 2975 2976 if (code > SMP_CMD_MAX) 2977 goto drop; 2978 2979 if (smp && !test_and_clear_bit(code, &smp->allow_cmd)) 2980 goto drop; 2981 2982 /* If we don't have a context the only allowed commands are 2983 * pairing request and security request. 2984 */ 2985 if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ) 2986 goto drop; 2987 2988 switch (code) { 2989 case SMP_CMD_PAIRING_REQ: 2990 reason = smp_cmd_pairing_req(conn, skb); 2991 break; 2992 2993 case SMP_CMD_PAIRING_FAIL: 2994 smp_failure(conn, 0); 2995 err = -EPERM; 2996 break; 2997 2998 case SMP_CMD_PAIRING_RSP: 2999 reason = smp_cmd_pairing_rsp(conn, skb); 3000 break; 3001 3002 case SMP_CMD_SECURITY_REQ: 3003 reason = smp_cmd_security_req(conn, skb); 3004 break; 3005 3006 case SMP_CMD_PAIRING_CONFIRM: 3007 reason = smp_cmd_pairing_confirm(conn, skb); 3008 break; 3009 3010 case SMP_CMD_PAIRING_RANDOM: 3011 reason = smp_cmd_pairing_random(conn, skb); 3012 break; 3013 3014 case SMP_CMD_ENCRYPT_INFO: 3015 reason = smp_cmd_encrypt_info(conn, skb); 3016 break; 3017 3018 case SMP_CMD_INITIATOR_IDENT: 3019 reason = smp_cmd_initiator_ident(conn, skb); 3020 break; 3021 3022 case SMP_CMD_IDENT_INFO: 3023 reason = smp_cmd_ident_info(conn, skb); 3024 break; 3025 3026 case SMP_CMD_IDENT_ADDR_INFO: 3027 reason = smp_cmd_ident_addr_info(conn, skb); 3028 break; 3029 3030 case SMP_CMD_SIGN_INFO: 3031 reason = smp_cmd_sign_info(conn, skb); 3032 break; 3033 3034 case SMP_CMD_PUBLIC_KEY: 3035 reason = smp_cmd_public_key(conn, skb); 3036 break; 3037 3038 case SMP_CMD_DHKEY_CHECK: 3039 reason = smp_cmd_dhkey_check(conn, skb); 3040 break; 3041 3042 case SMP_CMD_KEYPRESS_NOTIFY: 3043 reason = smp_cmd_keypress_notify(conn, skb); 3044 break; 3045 3046 default: 3047 bt_dev_dbg(hcon->hdev, "Unknown command code 0x%2.2x", code); 3048 reason = SMP_CMD_NOTSUPP; 3049 goto done; 3050 } 3051 3052done: 3053 if (!err) { 3054 if (reason) 3055 smp_failure(conn, reason); 3056 kfree_skb(skb); 3057 } 3058 3059 return err; 3060 3061drop: 3062 bt_dev_err(hcon->hdev, "unexpected SMP command 0x%02x from %pMR", 3063 code, &hcon->dst); 3064 kfree_skb(skb); 3065 return 0; 3066} 3067 3068static void smp_teardown_cb(struct l2cap_chan *chan, int err) 3069{ 3070 struct l2cap_conn *conn = chan->conn; 3071 3072 bt_dev_dbg(conn->hcon->hdev, "chan %p", chan); 3073 3074 if (chan->data) 3075 smp_chan_destroy(conn); 3076 3077 conn->smp = NULL; 3078 l2cap_chan_put(chan); 3079} 3080 3081static void bredr_pairing(struct l2cap_chan *chan) 3082{ 3083 struct l2cap_conn *conn = chan->conn; 3084 struct hci_conn *hcon = conn->hcon; 3085 struct hci_dev *hdev = hcon->hdev; 3086 struct smp_cmd_pairing req; 3087 struct smp_chan *smp; 3088 3089 bt_dev_dbg(hdev, "chan %p", chan); 3090 3091 /* Only new pairings are interesting */ 3092 if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags)) 3093 return; 3094 3095 /* Don't bother if we're not encrypted */ 3096 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3097 return; 3098 3099 /* Only initiator may initiate SMP over BR/EDR */ 3100 if (hcon->role != HCI_ROLE_MASTER) 3101 return; 3102 3103 /* Secure Connections support must be enabled */ 3104 if (!hci_dev_test_flag(hdev, HCI_SC_ENABLED)) 3105 return; 3106 3107 /* BR/EDR must use Secure Connections for SMP */ 3108 if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) && 3109 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3110 return; 3111 3112 /* If our LE support is not enabled don't do anything */ 3113 if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) 3114 return; 3115 3116 /* Don't bother if remote LE support is not enabled */ 3117 if (!lmp_host_le_capable(hcon)) 3118 return; 3119 3120 /* Remote must support SMP fixed chan for BR/EDR */ 3121 if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR)) 3122 return; 3123 3124 /* Don't bother if SMP is already ongoing */ 3125 if (chan->data) 3126 return; 3127 3128 smp = smp_chan_create(conn); 3129 if (!smp) { 3130 bt_dev_err(hdev, "unable to create SMP context for BR/EDR"); 3131 return; 3132 } 3133 3134 set_bit(SMP_FLAG_SC, &smp->flags); 3135 3136 bt_dev_dbg(hdev, "starting SMP over BR/EDR"); 3137 3138 /* Prepare and send the BR/EDR SMP Pairing Request */ 3139 build_bredr_pairing_cmd(smp, &req, NULL); 3140 3141 smp->preq[0] = SMP_CMD_PAIRING_REQ; 3142 memcpy(&smp->preq[1], &req, sizeof(req)); 3143 3144 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req); 3145 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 3146} 3147 3148static void smp_resume_cb(struct l2cap_chan *chan) 3149{ 3150 struct smp_chan *smp = chan->data; 3151 struct l2cap_conn *conn = chan->conn; 3152 struct hci_conn *hcon = conn->hcon; 3153 3154 bt_dev_dbg(hcon->hdev, "chan %p", chan); 3155 3156 if (hcon->type == ACL_LINK) { 3157 bredr_pairing(chan); 3158 return; 3159 } 3160 3161 if (!smp) 3162 return; 3163 3164 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3165 return; 3166 3167 cancel_delayed_work(&smp->security_timer); 3168 3169 smp_distribute_keys(smp); 3170} 3171 3172static void smp_ready_cb(struct l2cap_chan *chan) 3173{ 3174 struct l2cap_conn *conn = chan->conn; 3175 struct hci_conn *hcon = conn->hcon; 3176 3177 bt_dev_dbg(hcon->hdev, "chan %p", chan); 3178 3179 /* No need to call l2cap_chan_hold() here since we already own 3180 * the reference taken in smp_new_conn_cb(). This is just the 3181 * first time that we tie it to a specific pointer. The code in 3182 * l2cap_core.c ensures that there's no risk this function wont 3183 * get called if smp_new_conn_cb was previously called. 3184 */ 3185 conn->smp = chan; 3186 3187 if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3188 bredr_pairing(chan); 3189} 3190 3191static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb) 3192{ 3193 int err; 3194 3195 bt_dev_dbg(chan->conn->hcon->hdev, "chan %p", chan); 3196 3197 err = smp_sig_channel(chan, skb); 3198 if (err) { 3199 struct smp_chan *smp = chan->data; 3200 3201 if (smp) 3202 cancel_delayed_work_sync(&smp->security_timer); 3203 3204 hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE); 3205 } 3206 3207 return err; 3208} 3209 3210static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan, 3211 unsigned long hdr_len, 3212 unsigned long len, int nb) 3213{ 3214 struct sk_buff *skb; 3215 3216 skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL); 3217 if (!skb) 3218 return ERR_PTR(-ENOMEM); 3219 3220 skb->priority = HCI_PRIO_MAX; 3221 bt_cb(skb)->l2cap.chan = chan; 3222 3223 return skb; 3224} 3225 3226static const struct l2cap_ops smp_chan_ops = { 3227 .name = "Security Manager", 3228 .ready = smp_ready_cb, 3229 .recv = smp_recv_cb, 3230 .alloc_skb = smp_alloc_skb_cb, 3231 .teardown = smp_teardown_cb, 3232 .resume = smp_resume_cb, 3233 3234 .new_connection = l2cap_chan_no_new_connection, 3235 .state_change = l2cap_chan_no_state_change, 3236 .close = l2cap_chan_no_close, 3237 .defer = l2cap_chan_no_defer, 3238 .suspend = l2cap_chan_no_suspend, 3239 .set_shutdown = l2cap_chan_no_set_shutdown, 3240 .get_sndtimeo = l2cap_chan_no_get_sndtimeo, 3241}; 3242 3243static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan) 3244{ 3245 struct l2cap_chan *chan; 3246 3247 BT_DBG("pchan %p", pchan); 3248 3249 chan = l2cap_chan_create(); 3250 if (!chan) 3251 return NULL; 3252 3253 chan->chan_type = pchan->chan_type; 3254 chan->ops = &smp_chan_ops; 3255 chan->scid = pchan->scid; 3256 chan->dcid = chan->scid; 3257 chan->imtu = pchan->imtu; 3258 chan->omtu = pchan->omtu; 3259 chan->mode = pchan->mode; 3260 3261 /* Other L2CAP channels may request SMP routines in order to 3262 * change the security level. This means that the SMP channel 3263 * lock must be considered in its own category to avoid lockdep 3264 * warnings. 3265 */ 3266 atomic_set(&chan->nesting, L2CAP_NESTING_SMP); 3267 3268 BT_DBG("created chan %p", chan); 3269 3270 return chan; 3271} 3272 3273static const struct l2cap_ops smp_root_chan_ops = { 3274 .name = "Security Manager Root", 3275 .new_connection = smp_new_conn_cb, 3276 3277 /* None of these are implemented for the root channel */ 3278 .close = l2cap_chan_no_close, 3279 .alloc_skb = l2cap_chan_no_alloc_skb, 3280 .recv = l2cap_chan_no_recv, 3281 .state_change = l2cap_chan_no_state_change, 3282 .teardown = l2cap_chan_no_teardown, 3283 .ready = l2cap_chan_no_ready, 3284 .defer = l2cap_chan_no_defer, 3285 .suspend = l2cap_chan_no_suspend, 3286 .resume = l2cap_chan_no_resume, 3287 .set_shutdown = l2cap_chan_no_set_shutdown, 3288 .get_sndtimeo = l2cap_chan_no_get_sndtimeo, 3289}; 3290 3291static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid) 3292{ 3293 struct l2cap_chan *chan; 3294 struct smp_dev *smp; 3295 struct crypto_shash *tfm_cmac; 3296 struct crypto_kpp *tfm_ecdh; 3297 3298 if (cid == L2CAP_CID_SMP_BREDR) { 3299 smp = NULL; 3300 goto create_chan; 3301 } 3302 3303 smp = kzalloc(sizeof(*smp), GFP_KERNEL); 3304 if (!smp) 3305 return ERR_PTR(-ENOMEM); 3306 3307 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 3308 if (IS_ERR(tfm_cmac)) { 3309 bt_dev_err(hdev, "Unable to create CMAC crypto context"); 3310 kfree_sensitive(smp); 3311 return ERR_CAST(tfm_cmac); 3312 } 3313 3314 tfm_ecdh = crypto_alloc_kpp("ecdh-nist-p256", 0, 0); 3315 if (IS_ERR(tfm_ecdh)) { 3316 bt_dev_err(hdev, "Unable to create ECDH crypto context"); 3317 crypto_free_shash(tfm_cmac); 3318 kfree_sensitive(smp); 3319 return ERR_CAST(tfm_ecdh); 3320 } 3321 3322 smp->local_oob = false; 3323 smp->tfm_cmac = tfm_cmac; 3324 smp->tfm_ecdh = tfm_ecdh; 3325 3326create_chan: 3327 chan = l2cap_chan_create(); 3328 if (!chan) { 3329 if (smp) { 3330 crypto_free_shash(smp->tfm_cmac); 3331 crypto_free_kpp(smp->tfm_ecdh); 3332 kfree_sensitive(smp); 3333 } 3334 return ERR_PTR(-ENOMEM); 3335 } 3336 3337 chan->data = smp; 3338 3339 l2cap_add_scid(chan, cid); 3340 3341 l2cap_chan_set_defaults(chan); 3342 3343 if (cid == L2CAP_CID_SMP) { 3344 u8 bdaddr_type; 3345 3346 hci_copy_identity_address(hdev, &chan->src, &bdaddr_type); 3347 3348 if (bdaddr_type == ADDR_LE_DEV_PUBLIC) 3349 chan->src_type = BDADDR_LE_PUBLIC; 3350 else 3351 chan->src_type = BDADDR_LE_RANDOM; 3352 } else { 3353 bacpy(&chan->src, &hdev->bdaddr); 3354 chan->src_type = BDADDR_BREDR; 3355 } 3356 3357 chan->state = BT_LISTEN; 3358 chan->mode = L2CAP_MODE_BASIC; 3359 chan->imtu = L2CAP_DEFAULT_MTU; 3360 chan->ops = &smp_root_chan_ops; 3361 3362 /* Set correct nesting level for a parent/listening channel */ 3363 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT); 3364 3365 return chan; 3366} 3367 3368static void smp_del_chan(struct l2cap_chan *chan) 3369{ 3370 struct smp_dev *smp; 3371 3372 BT_DBG("chan %p", chan); 3373 3374 smp = chan->data; 3375 if (smp) { 3376 chan->data = NULL; 3377 crypto_free_shash(smp->tfm_cmac); 3378 crypto_free_kpp(smp->tfm_ecdh); 3379 kfree_sensitive(smp); 3380 } 3381 3382 l2cap_chan_put(chan); 3383} 3384 3385int smp_force_bredr(struct hci_dev *hdev, bool enable) 3386{ 3387 if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3388 return -EALREADY; 3389 3390 if (enable) { 3391 struct l2cap_chan *chan; 3392 3393 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR); 3394 if (IS_ERR(chan)) 3395 return PTR_ERR(chan); 3396 3397 hdev->smp_bredr_data = chan; 3398 } else { 3399 struct l2cap_chan *chan; 3400 3401 chan = hdev->smp_bredr_data; 3402 hdev->smp_bredr_data = NULL; 3403 smp_del_chan(chan); 3404 } 3405 3406 hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP); 3407 3408 return 0; 3409} 3410 3411int smp_register(struct hci_dev *hdev) 3412{ 3413 struct l2cap_chan *chan; 3414 3415 bt_dev_dbg(hdev, ""); 3416 3417 /* If the controller does not support Low Energy operation, then 3418 * there is also no need to register any SMP channel. 3419 */ 3420 if (!lmp_le_capable(hdev)) 3421 return 0; 3422 3423 if (WARN_ON(hdev->smp_data)) { 3424 chan = hdev->smp_data; 3425 hdev->smp_data = NULL; 3426 smp_del_chan(chan); 3427 } 3428 3429 chan = smp_add_cid(hdev, L2CAP_CID_SMP); 3430 if (IS_ERR(chan)) 3431 return PTR_ERR(chan); 3432 3433 hdev->smp_data = chan; 3434 3435 if (!lmp_sc_capable(hdev)) { 3436 /* Flag can be already set here (due to power toggle) */ 3437 if (!hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3438 return 0; 3439 } 3440 3441 if (WARN_ON(hdev->smp_bredr_data)) { 3442 chan = hdev->smp_bredr_data; 3443 hdev->smp_bredr_data = NULL; 3444 smp_del_chan(chan); 3445 } 3446 3447 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR); 3448 if (IS_ERR(chan)) { 3449 int err = PTR_ERR(chan); 3450 chan = hdev->smp_data; 3451 hdev->smp_data = NULL; 3452 smp_del_chan(chan); 3453 return err; 3454 } 3455 3456 hdev->smp_bredr_data = chan; 3457 3458 return 0; 3459} 3460 3461void smp_unregister(struct hci_dev *hdev) 3462{ 3463 struct l2cap_chan *chan; 3464 3465 if (hdev->smp_bredr_data) { 3466 chan = hdev->smp_bredr_data; 3467 hdev->smp_bredr_data = NULL; 3468 smp_del_chan(chan); 3469 } 3470 3471 if (hdev->smp_data) { 3472 chan = hdev->smp_data; 3473 hdev->smp_data = NULL; 3474 smp_del_chan(chan); 3475 } 3476} 3477 3478#if IS_ENABLED(CONFIG_BT_SELFTEST_SMP) 3479 3480static int __init test_debug_key(struct crypto_kpp *tfm_ecdh) 3481{ 3482 u8 pk[64]; 3483 int err; 3484 3485 err = set_ecdh_privkey(tfm_ecdh, debug_sk); 3486 if (err) 3487 return err; 3488 3489 err = generate_ecdh_public_key(tfm_ecdh, pk); 3490 if (err) 3491 return err; 3492 3493 if (crypto_memneq(pk, debug_pk, 64)) 3494 return -EINVAL; 3495 3496 return 0; 3497} 3498 3499static int __init test_ah(void) 3500{ 3501 const u8 irk[16] = { 3502 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3503 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3504 const u8 r[3] = { 0x94, 0x81, 0x70 }; 3505 const u8 exp[3] = { 0xaa, 0xfb, 0x0d }; 3506 u8 res[3]; 3507 int err; 3508 3509 err = smp_ah(irk, r, res); 3510 if (err) 3511 return err; 3512 3513 if (crypto_memneq(res, exp, 3)) 3514 return -EINVAL; 3515 3516 return 0; 3517} 3518 3519static int __init test_c1(void) 3520{ 3521 const u8 k[16] = { 3522 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 3523 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 3524 const u8 r[16] = { 3525 0xe0, 0x2e, 0x70, 0xc6, 0x4e, 0x27, 0x88, 0x63, 3526 0x0e, 0x6f, 0xad, 0x56, 0x21, 0xd5, 0x83, 0x57 }; 3527 const u8 preq[7] = { 0x01, 0x01, 0x00, 0x00, 0x10, 0x07, 0x07 }; 3528 const u8 pres[7] = { 0x02, 0x03, 0x00, 0x00, 0x08, 0x00, 0x05 }; 3529 const u8 _iat = 0x01; 3530 const u8 _rat = 0x00; 3531 const bdaddr_t ra = { { 0xb6, 0xb5, 0xb4, 0xb3, 0xb2, 0xb1 } }; 3532 const bdaddr_t ia = { { 0xa6, 0xa5, 0xa4, 0xa3, 0xa2, 0xa1 } }; 3533 const u8 exp[16] = { 3534 0x86, 0x3b, 0xf1, 0xbe, 0xc5, 0x4d, 0xa7, 0xd2, 3535 0xea, 0x88, 0x89, 0x87, 0xef, 0x3f, 0x1e, 0x1e }; 3536 u8 res[16]; 3537 int err; 3538 3539 err = smp_c1(k, r, preq, pres, _iat, &ia, _rat, &ra, res); 3540 if (err) 3541 return err; 3542 3543 if (crypto_memneq(res, exp, 16)) 3544 return -EINVAL; 3545 3546 return 0; 3547} 3548 3549static int __init test_s1(void) 3550{ 3551 const u8 k[16] = { 3552 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 3553 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 3554 const u8 r1[16] = { 3555 0x88, 0x77, 0x66, 0x55, 0x44, 0x33, 0x22, 0x11 }; 3556 const u8 r2[16] = { 3557 0x00, 0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa, 0x99 }; 3558 const u8 exp[16] = { 3559 0x62, 0xa0, 0x6d, 0x79, 0xae, 0x16, 0x42, 0x5b, 3560 0x9b, 0xf4, 0xb0, 0xe8, 0xf0, 0xe1, 0x1f, 0x9a }; 3561 u8 res[16]; 3562 int err; 3563 3564 err = smp_s1(k, r1, r2, res); 3565 if (err) 3566 return err; 3567 3568 if (crypto_memneq(res, exp, 16)) 3569 return -EINVAL; 3570 3571 return 0; 3572} 3573 3574static int __init test_f4(struct crypto_shash *tfm_cmac) 3575{ 3576 const u8 u[32] = { 3577 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 3578 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 3579 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 3580 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 }; 3581 const u8 v[32] = { 3582 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b, 3583 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59, 3584 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90, 3585 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 }; 3586 const u8 x[16] = { 3587 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3588 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3589 const u8 z = 0x00; 3590 const u8 exp[16] = { 3591 0x2d, 0x87, 0x74, 0xa9, 0xbe, 0xa1, 0xed, 0xf1, 3592 0x1c, 0xbd, 0xa9, 0x07, 0xf1, 0x16, 0xc9, 0xf2 }; 3593 u8 res[16]; 3594 int err; 3595 3596 err = smp_f4(tfm_cmac, u, v, x, z, res); 3597 if (err) 3598 return err; 3599 3600 if (crypto_memneq(res, exp, 16)) 3601 return -EINVAL; 3602 3603 return 0; 3604} 3605 3606static int __init test_f5(struct crypto_shash *tfm_cmac) 3607{ 3608 const u8 w[32] = { 3609 0x98, 0xa6, 0xbf, 0x73, 0xf3, 0x34, 0x8d, 0x86, 3610 0xf1, 0x66, 0xf8, 0xb4, 0x13, 0x6b, 0x79, 0x99, 3611 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3612 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3613 const u8 n1[16] = { 3614 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3615 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3616 const u8 n2[16] = { 3617 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3618 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3619 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 }; 3620 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 }; 3621 const u8 exp_ltk[16] = { 3622 0x38, 0x0a, 0x75, 0x94, 0xb5, 0x22, 0x05, 0x98, 3623 0x23, 0xcd, 0xd7, 0x69, 0x11, 0x79, 0x86, 0x69 }; 3624 const u8 exp_mackey[16] = { 3625 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd, 3626 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 }; 3627 u8 mackey[16], ltk[16]; 3628 int err; 3629 3630 err = smp_f5(tfm_cmac, w, n1, n2, a1, a2, mackey, ltk); 3631 if (err) 3632 return err; 3633 3634 if (crypto_memneq(mackey, exp_mackey, 16)) 3635 return -EINVAL; 3636 3637 if (crypto_memneq(ltk, exp_ltk, 16)) 3638 return -EINVAL; 3639 3640 return 0; 3641} 3642 3643static int __init test_f6(struct crypto_shash *tfm_cmac) 3644{ 3645 const u8 w[16] = { 3646 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd, 3647 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 }; 3648 const u8 n1[16] = { 3649 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3650 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3651 const u8 n2[16] = { 3652 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3653 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3654 const u8 r[16] = { 3655 0xc8, 0x0f, 0x2d, 0x0c, 0xd2, 0x42, 0xda, 0x08, 3656 0x54, 0xbb, 0x53, 0xb4, 0x3b, 0x34, 0xa3, 0x12 }; 3657 const u8 io_cap[3] = { 0x02, 0x01, 0x01 }; 3658 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 }; 3659 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 }; 3660 const u8 exp[16] = { 3661 0x61, 0x8f, 0x95, 0xda, 0x09, 0x0b, 0x6c, 0xd2, 3662 0xc5, 0xe8, 0xd0, 0x9c, 0x98, 0x73, 0xc4, 0xe3 }; 3663 u8 res[16]; 3664 int err; 3665 3666 err = smp_f6(tfm_cmac, w, n1, n2, r, io_cap, a1, a2, res); 3667 if (err) 3668 return err; 3669 3670 if (crypto_memneq(res, exp, 16)) 3671 return -EINVAL; 3672 3673 return 0; 3674} 3675 3676static int __init test_g2(struct crypto_shash *tfm_cmac) 3677{ 3678 const u8 u[32] = { 3679 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 3680 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 3681 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 3682 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 }; 3683 const u8 v[32] = { 3684 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b, 3685 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59, 3686 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90, 3687 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 }; 3688 const u8 x[16] = { 3689 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3690 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3691 const u8 y[16] = { 3692 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3693 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3694 const u32 exp_val = 0x2f9ed5ba % 1000000; 3695 u32 val; 3696 int err; 3697 3698 err = smp_g2(tfm_cmac, u, v, x, y, &val); 3699 if (err) 3700 return err; 3701 3702 if (val != exp_val) 3703 return -EINVAL; 3704 3705 return 0; 3706} 3707 3708static int __init test_h6(struct crypto_shash *tfm_cmac) 3709{ 3710 const u8 w[16] = { 3711 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3712 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3713 const u8 key_id[4] = { 0x72, 0x62, 0x65, 0x6c }; 3714 const u8 exp[16] = { 3715 0x99, 0x63, 0xb1, 0x80, 0xe2, 0xa9, 0xd3, 0xe8, 3716 0x1c, 0xc9, 0x6d, 0xe7, 0x02, 0xe1, 0x9a, 0x2d }; 3717 u8 res[16]; 3718 int err; 3719 3720 err = smp_h6(tfm_cmac, w, key_id, res); 3721 if (err) 3722 return err; 3723 3724 if (crypto_memneq(res, exp, 16)) 3725 return -EINVAL; 3726 3727 return 0; 3728} 3729 3730static char test_smp_buffer[32]; 3731 3732static ssize_t test_smp_read(struct file *file, char __user *user_buf, 3733 size_t count, loff_t *ppos) 3734{ 3735 return simple_read_from_buffer(user_buf, count, ppos, test_smp_buffer, 3736 strlen(test_smp_buffer)); 3737} 3738 3739static const struct file_operations test_smp_fops = { 3740 .open = simple_open, 3741 .read = test_smp_read, 3742 .llseek = default_llseek, 3743}; 3744 3745static int __init run_selftests(struct crypto_shash *tfm_cmac, 3746 struct crypto_kpp *tfm_ecdh) 3747{ 3748 ktime_t calltime, delta, rettime; 3749 unsigned long long duration; 3750 int err; 3751 3752 calltime = ktime_get(); 3753 3754 err = test_debug_key(tfm_ecdh); 3755 if (err) { 3756 BT_ERR("debug_key test failed"); 3757 goto done; 3758 } 3759 3760 err = test_ah(); 3761 if (err) { 3762 BT_ERR("smp_ah test failed"); 3763 goto done; 3764 } 3765 3766 err = test_c1(); 3767 if (err) { 3768 BT_ERR("smp_c1 test failed"); 3769 goto done; 3770 } 3771 3772 err = test_s1(); 3773 if (err) { 3774 BT_ERR("smp_s1 test failed"); 3775 goto done; 3776 } 3777 3778 err = test_f4(tfm_cmac); 3779 if (err) { 3780 BT_ERR("smp_f4 test failed"); 3781 goto done; 3782 } 3783 3784 err = test_f5(tfm_cmac); 3785 if (err) { 3786 BT_ERR("smp_f5 test failed"); 3787 goto done; 3788 } 3789 3790 err = test_f6(tfm_cmac); 3791 if (err) { 3792 BT_ERR("smp_f6 test failed"); 3793 goto done; 3794 } 3795 3796 err = test_g2(tfm_cmac); 3797 if (err) { 3798 BT_ERR("smp_g2 test failed"); 3799 goto done; 3800 } 3801 3802 err = test_h6(tfm_cmac); 3803 if (err) { 3804 BT_ERR("smp_h6 test failed"); 3805 goto done; 3806 } 3807 3808 rettime = ktime_get(); 3809 delta = ktime_sub(rettime, calltime); 3810 duration = (unsigned long long) ktime_to_ns(delta) >> 10; 3811 3812 BT_INFO("SMP test passed in %llu usecs", duration); 3813 3814done: 3815 if (!err) 3816 snprintf(test_smp_buffer, sizeof(test_smp_buffer), 3817 "PASS (%llu usecs)\n", duration); 3818 else 3819 snprintf(test_smp_buffer, sizeof(test_smp_buffer), "FAIL\n"); 3820 3821 debugfs_create_file("selftest_smp", 0444, bt_debugfs, NULL, 3822 &test_smp_fops); 3823 3824 return err; 3825} 3826 3827int __init bt_selftest_smp(void) 3828{ 3829 struct crypto_shash *tfm_cmac; 3830 struct crypto_kpp *tfm_ecdh; 3831 int err; 3832 3833 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 3834 if (IS_ERR(tfm_cmac)) { 3835 BT_ERR("Unable to create CMAC crypto context"); 3836 return PTR_ERR(tfm_cmac); 3837 } 3838 3839 tfm_ecdh = crypto_alloc_kpp("ecdh-nist-p256", 0, 0); 3840 if (IS_ERR(tfm_ecdh)) { 3841 BT_ERR("Unable to create ECDH crypto context"); 3842 crypto_free_shash(tfm_cmac); 3843 return PTR_ERR(tfm_ecdh); 3844 } 3845 3846 err = run_selftests(tfm_cmac, tfm_ecdh); 3847 3848 crypto_free_shash(tfm_cmac); 3849 crypto_free_kpp(tfm_ecdh); 3850 3851 return err; 3852} 3853 3854#endif 3855